51
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Fickling SD, Poel DN, Dorman JC, D’Arcy RCN, Munce TA. Subconcussive changes in youth football players: objective evidence using brain vital signs and instrumented accelerometers. Brain Commun 2021; 4:fcab286. [PMID: 35291689 PMCID: PMC8914875 DOI: 10.1093/braincomms/fcab286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 10/05/2021] [Accepted: 10/11/2021] [Indexed: 11/25/2022] Open
Abstract
Brain vital signs, measured by EEG, were used for portable, objective,
neurophysiological evaluation of cognitive function in youth tackle football
players. Specifically, we investigated whether previously reported pre- and
post-season subconcussive changes detected in youth ice hockey players were
comparably detected in football. The two objectives were to: (i) replicate
previously published results showing subconcussive cognitive deficits; and (ii)
the relationship between brain vital sign changes and head-impact exposure.
Using a longitudinal design, 15 male football players (age
12.89 ± 0.35 years) were tested pre- and
post-season, with none having a concussion diagnosis during the season. Peak
latencies and amplitudes were quantified for Auditory sensation (N100), Basic
attention (P300) and Cognitive processing (N400). Regression analyses tested the
relationships between these brain vital signs and exposure to head impacts
through both number of impacts sustained, and total sessions (practices and
games) participated. The results demonstrated significant pre/post differences
in N400 latencies, with ∼70 ms delay
(P < 0.01), replicating prior findings.
Regression analysis also showed significant linear relationships between brain
vital signs changes and head impact exposure based on accelerometer data and
games/practices played (highest
R = 0.863, P
< 0.001 for overall sessions). Number of head impacts in youth
football (age 12–14 years) findings corresponded most closely
with prior Junior-A ice hockey (age 16–21 years) findings,
suggesting comparable contact levels at younger ages in football. The predictive
relationship of brain vital signs provided a notable complement to instrumented
accelerometers, with a direct physiological measure of potential individual
exposure to subconcussive impacts.
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Affiliation(s)
- Shaun D Fickling
- Faculty of Sciences and Applied Sciences, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
- BrainNET, Health and Technology District, Surrey, BC V3V 0C6, Canada
- Center for Neurology Studies, HealthTech Connex, Surrey, BC V3V 0C6, Canada
| | - Daniel N Poel
- Sanford Sports Science Institute, Sanford Health, Sioux Falls, SD 57107, USA
- Environmental Influences on Health and Disease Group, Sanford Research, Sioux Falls, SD 57104, USA
| | - Jason C Dorman
- Sanford Sports Science Institute, Sanford Health, Sioux Falls, SD 57107, USA
- Environmental Influences on Health and Disease Group, Sanford Research, Sioux Falls, SD 57104, USA
| | - Ryan C N D’Arcy
- Faculty of Sciences and Applied Sciences, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
- BrainNET, Health and Technology District, Surrey, BC V3V 0C6, Canada
- Center for Neurology Studies, HealthTech Connex, Surrey, BC V3V 0C6, Canada
| | - Thayne A Munce
- Sanford Sports Science Institute, Sanford Health, Sioux Falls, SD 57107, USA
- Environmental Influences on Health and Disease Group, Sanford Research, Sioux Falls, SD 57104, USA
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52
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Gallagher VT, Murthy P, Stocks J, Vesci B, Mjaanes J, Chen Y, Breiter HC, LaBella C, Herrold AA, Reilly JL. Eye Movements Detect Differential Change after Participation in Male Collegiate Collision versus Non-Collision Sports. Neurotrauma Rep 2021; 2:440-452. [PMID: 34901940 PMCID: PMC8655805 DOI: 10.1089/neur.2021.0030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Although neuroimaging studies of collision (COLL) sport athletes demonstrate alterations in brain structure and function from pre- to post-season, reliable tools to detect behavioral/cognitive change relevant to functional networks associated with participation in collision sports are lacking. This study evaluated the use of eye-movement testing to detect change in cognitive and sensorimotor processing among male club collegiate athletes after one season of participation in collision sports of variable exposure. We predicted that COLL (High Dose [hockey], n = 8; Low Dose [rugby], n = 9) would demonstrate longer reaction times (antisaccade and memory-guided saccade [MGS] latencies), increased inhibitory errors (antisaccade error rate), and poorer spatial working memory (MGS spatial accuracy) at post-season, relative to pre-season, whereas non-collision collegiate athletes (NON-COLL; n = 17) would remain stable. We also predicted that whereas eye-movement performance would detect pre- to post-season change, ImPACT (Immediate Post-Concussion Assessment and Cognitive Test) performance would remain stable. Our data showed that NON-COLL had shorter (improved performance) post- versus pre-season antisaccade and MGS latencies, whereas COLL groups showed stable, longer, or attenuated reduction in latency (ps ≤ 0.001). Groups did not differ in antisaccade error rate. On the MGS task, NON-COLL demonstrated improved spatial accuracy over time, whereas COLL groups showed reduced spatial accuracy (p < 0.05, uncorrected). No differential change was observed on ImPACT. This study provides preliminary evidence for eye-movement testing as a sensitive marker of subtle changes in attentional control and working memory resulting from participation in sports with varying levels of subconcussive exposure.
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Affiliation(s)
| | - Prianka Murthy
- Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Jane Stocks
- Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Brian Vesci
- Department of Sports Medicine, Northwestern University, Evanston, Illinois, USA
| | - Jeffrey Mjaanes
- Department of Sports Medicine, Northwestern University, Evanston, Illinois, USA
| | - Yufen Chen
- Center for Translational Imaging, Northwestern University, Evanston, Illinois, USA
| | - Hans C Breiter
- Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Cynthia LaBella
- Division of Orthopedics and Sports Medicine, Ann & Robert H Lurie Children's Hospital of Chicago, Chicago, Illinois, USA
| | - Amy A Herrold
- Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - James L Reilly
- Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
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53
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Mishra S, Singh VJ, Chawla PA, Chawla V. Neuroprotective Role of Nutritional Supplementation in Athletes. Curr Mol Pharmacol 2021; 15:129-142. [PMID: 34886789 DOI: 10.2174/1874467214666211209144721] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 06/22/2021] [Accepted: 08/31/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND Neurodegenerative disorders belong to different classes of progressive/chronic conditions that affect the peripheral/central nervous system. It has been shown through studies that athletes who play sports involving repeated head trauma and sub-concussive impacts are more likely to experience neurological impairments and neurodegenerative disorders in the long run. AIMS The aim of the current narrative review article is to provide a summary of various nutraceuticals that offer promise in the prevention or management of sports-related injuries, especially concussions and mild traumatic brain injuries. METHODS This article reviews the various potential nutraceutical agents and their possible mechanisms in providing a beneficial effect in the injury recovery process. A thorough survey of the literature was carried out in the relevant databases to identify studies published in recent years. In the present article, we have also highlighted the major neurological disorders along with the associated nutraceutical(s) therapy in the management of disorders. RESULTS The exact pathological mechanism behind neurodegenerative conditions is complex as well as idiopathic. However, mitochondrial dysfunction, oxidative stress as well as intracellular calcium overload are some common reasons responsible for the progression of these neurodegenerative disorders. Owing to the multifaceted effects of nutraceuticals (complementary medicine), these supplements have gained importance as neuroprotective. These diet-based approaches inhibit different pathways in a physiological manner without eliciting adverse effects. Food habits and lifestyle of an individual also affect neurodegeneration. CONCLUSION Studies have shown nutraceuticals (such as resveratrol, omega-3-fatty acids) to be efficacious in terms of their neuroprotection against several neurodegenerative disorders and to be used as supplements in the management of traumatic brain injuries. Protection prior to injuries is needed since concussions or sub-concussive impacts may trigger several pathophysiological responses or cascades that can lead to long-term complications associated with CNS. Thus, the use of nutraceuticals as prophylactic treatment for neurological interventions has been proposed.
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Affiliation(s)
- Supriya Mishra
- Department of Pharmacology, SRM College of Pharmacy, Delhi-NCR. India
| | - Vikram Jeet Singh
- Department of Pharmaceutical Chemistry and Analysis, ISF College of Pharmacy, Moga-142001, Punjab. India
| | - Pooja A Chawla
- Department of Pharmaceutical Chemistry and Analysis, ISF College of Pharmacy, Moga-142001, Punjab. India
| | - Viney Chawla
- Department of Pharmaceutics, University Institute of Pharmaceutical Sciences and Research, Baba Farid University of Health Sciences, Faridkot-151203, Punjab. India
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54
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Goodin P, Gardner AJ, Dokani N, Nizette B, Ahmadizadeh S, Edwards S, Iverson GL. Development of a Machine-Learning-Based Classifier for the Identification of Head and Body Impacts in Elite Level Australian Rules Football Players. Front Sports Act Living 2021; 3:725245. [PMID: 34870193 PMCID: PMC8640084 DOI: 10.3389/fspor.2021.725245] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 10/13/2021] [Indexed: 11/30/2022] Open
Abstract
Background: Exposure to thousands of head and body impacts during a career in contact and collision sports may contribute to current or later life issues related to brain health. Wearable technology enables the measurement of impact exposure. The validation of impact detection is required for accurate exposure monitoring. In this study, we present a method of automatic identification (classification) of head and body impacts using an instrumented mouthguard, video-verified impacts, and machine-learning algorithms. Methods: Time series data were collected via the Nexus A9 mouthguard from 60 elite level men (mean age = 26.33; SD = 3.79) and four women (mean age = 25.50; SD = 5.91) from the Australian Rules Football players from eight clubs, participating in 119 games during the 2020 season. Ground truth data labeling on the captures used in this machine learning study was performed through the analysis of game footage by two expert video reviewers using SportCode and Catapult Vision. The visual labeling process occurred independently of the mouthguard time series data. True positive captures (captures where the reviewer directly observed contact between the mouthguard wearer and another player, the ball, or the ground) were defined as hits. Spectral and convolutional kernel based features were extracted from time series data. Performances of untuned classification algorithms from scikit-learn in addition to XGBoost were assessed to select the best performing baseline method for tuning. Results: Based on performance, XGBoost was selected as the classifier algorithm for tuning. A total of 13,712 video verified captures were collected and used to train and validate the classifier. True positive detection ranged from 94.67% in the Test set to 100% in the hold out set. True negatives ranged from 95.65 to 96.83% in the test and rest sets, respectively. Discussion and conclusion: This study suggests the potential for high performing impact classification models to be used for Australian Rules Football and highlights the importance of frequencies <150 Hz for the identification of these impacts.
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Affiliation(s)
- Peter Goodin
- School of Medicine, The University of Melbourne, Parkville, VIC, Australia.,HitIQ Ltd., South Melbourne, VIC, Australia
| | - Andrew J Gardner
- Priority Research Centre for Stroke and Brain Injury, School of Medicine and Public Health, University of Newcastle, Callaghan, NSW, Australia.,Hunter New England Local Health District Sports Concussion Clinic Research Program, Calvary Mater Hospital, Waratah, NSW, Australia.,Hunter Medical Research Institute, New Lambton Heights, NSW, Australia
| | | | | | | | - Suzi Edwards
- Priority Research Centre for Stroke and Brain Injury, School of Medicine and Public Health, University of Newcastle, Callaghan, NSW, Australia.,School of Environmental and Life Sciences, The University of Newcastle, Ourimbah, NSW, Australia.,Priority Research Centre for Physical Activity and Nutrition, The University of Newcastle, Callaghan, NSW, Australia
| | - Grant L Iverson
- Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, MA, United States.,Department of Physical Medicine and Rehabilitation, Spaulding Rehabilitation Hospital, Charlestown, MA, United States.,Spaulding Research Institute, Charlestown, MA, United States.,Sports Concussion Program, MassGeneral Hospital for Children, Boston, MA, United States.,Home Base, A Red Sox Foundation and Massachusetts General Hospital Program, Charlestown, MA, United States
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55
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Powell D, Stuart S, Godfrey A. Sports related concussion: an emerging era in digital sports technology. NPJ Digit Med 2021; 4:164. [PMID: 34857868 PMCID: PMC8639973 DOI: 10.1038/s41746-021-00538-w] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 10/19/2021] [Indexed: 11/24/2022] Open
Abstract
Sports-related concussion (SRC) is defined as a mild traumatic brain injury (mTBI) leading to complex impairment(s) in neurological function with many seemingly hidden or difficult to measure impairments that can deteriorate rapidly without any prior indication. Growing numbers of SRCs in professional and amateur contact sports have prompted closer dialog regarding player safety and welfare. Greater emphasis on awareness and education has improved SRC management, but also highlighted the difficulties of diagnosing SRC in a timely manner, particularly during matches or immediately after competition. Therefore, challenges exist in off-field assessment and return to play (RTP) protocols, with current traditional (subjective) approaches largely based on infrequent snapshot assessments. Low-cost digital technologies may provide more objective, integrated and personalized SRC assessment to better inform RTP protocols whilst also enhancing the efficiency and precision of healthcare assessment. To fully realize the potential of digital technologies in the diagnosis and management of SRC will require a significant paradigm shift in clinical practice and mindset. Here, we provide insights into SRC clinical assessment methods and the translational utility of digital approaches, with a focus on off-field digital techniques to detect key SRC metrics/biomarkers. We also provide insights and recommendations to the common benefits and challenges facing digital approaches as they aim to transition from novel technologies to an efficient, valid, reliable, and integrated clinical assessment tool for SRC. Finally, we highlight future opportunities that digital approaches have in SRC assessment and management including digital twinning and the "digital athlete".
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Affiliation(s)
- Dylan Powell
- Department of Computer and Information Sciences, Faculty of Engineering and Environment, Northumbria University, Newcastle upon Tyne, NE1 8ST, UK
| | - Sam Stuart
- Department of Sports, Exercise and Rehabilitation, Northumbria University, Newcastle upon Tyne, UK
| | - Alan Godfrey
- Department of Computer and Information Sciences, Faculty of Engineering and Environment, Northumbria University, Newcastle upon Tyne, NE1 8ST, UK.
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56
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Iverson GL, Deep-Soboslay A, Hyde TM, Kleinman JE, Erskine B, Fisher-Hubbard A, deJong JL, Castellani RJ. Suicide in Older Adult Men Is Not Related to a Personal History of Participation in Football. Front Neurol 2021; 12:745824. [PMID: 34899570 PMCID: PMC8662809 DOI: 10.3389/fneur.2021.745824] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 10/28/2021] [Indexed: 12/11/2022] Open
Abstract
Introduction: It is reasonable to estimate that tens of millions of men in the United States played high school football. There is societal concern that participation in football confers risk for later-in-life mental health problems. The purpose of this study is to examine whether there is an association between a personal history of playing high school football and death by suicide. Methods: The subjects were obtained from the Lieber Institute for Brain Development (LIBD) brain donation program in collaboration with the Office of the Medical Examiner at Western Michigan University Homer Stryker MD School of Medicine. Donor history was documented via medical records, mental health records, and telephone interviews with the next-of-kin. Results: The sample included 198 men aged 50 or older (median = 65.0 years, interquartile range = 57-75). There were 34.8% who participated in contact sports during high school (including football), and 29.8% participated in high school football. Approximately one-third of the sample had suicide as their manner of death (34.8%). There was no statistically significant difference in the proportions of suicide as a manner of death among those men with a personal history of playing football compared to men who did not play football or who did not play sports (p = 0.070, Odds Ratio, OR = 0.537). Those who played football were significantly less likely to have a lifetime history of a suicide attempt (p = 0.012, OR = 0.352). Men with mood disorders (p < 0.001, OR = 10.712), substance use disorders (p < 0.020, OR = 2.075), and those with a history of suicide ideation (p < 0.001, OR = 8.038) or attempts (p < 0.001, OR = 40.634) were more likely to have suicide as a manner of death. Moreover, those men with a family history of suicide were more likely to have prior suicide attempts (p = 0.031, OR = 2.153) and to have completed suicide (p = 0.001, OR = 2.927). Discussion: Suicide was related to well-established risk factors such as a personal history of a mood disorder, substance abuse disorder, prior suicide ideation, suicide attempts, and a family history of suicide attempts. This study adds to a steadily growing body of evidence suggesting that playing high school football is not associated with increased risk for suicidality or suicide during adulthood.
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Affiliation(s)
- Grant L. Iverson
- Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, MA, United States
- Spaulding Rehabilitation Hospital, Charlestown, MA, United States
- Spaulding Research Institute, Charlestown, MA, United States
- MassGeneral Hospital for Children Sports Concussion Program, Boston, MA, United States
- Home Base, A Red Sox Foundation and Massachusetts General Hospital Program, Charlestown, MA, United States
| | - Amy Deep-Soboslay
- Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, MD, United States
| | - Thomas M. Hyde
- Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, MD, United States
- Department of Psychiatry & Behavioral Sciences, Johns Hopkins School of Medicine, Baltimore, MD, United States
- Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, United States
| | - Joel E. Kleinman
- Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, MD, United States
- Department of Psychiatry & Behavioral Sciences, Johns Hopkins School of Medicine, Baltimore, MD, United States
| | - Brittany Erskine
- Department of Pathology, Western Michigan University Homer Stryker M.D. School of Medicine, Kalamazoo, MI, United States
| | - Amanda Fisher-Hubbard
- Department of Pathology, Western Michigan University Homer Stryker M.D. School of Medicine, Kalamazoo, MI, United States
| | - Joyce L. deJong
- Department of Pathology, Western Michigan University Homer Stryker M.D. School of Medicine, Kalamazoo, MI, United States
| | - Rudolph J. Castellani
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
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57
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Iverson GL, Merz ZC, Terry DP. Playing High School Football Is Not Associated With an Increased Risk for Suicidality in Early Adulthood. Clin J Sport Med 2021; 31:469-474. [PMID: 34704972 DOI: 10.1097/jsm.0000000000000890] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 08/12/2020] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To determine if playing high school football is associated with suicide ideation between the ages of 24 and 32 years. DESIGN Data were analyzed from the National Longitudinal Study of Adolescent to Adult Health. This prospective cohort study sampled nationally representative US participants at 4 time points from 1994 to 2008. SETTING In-home assessment. PARTICIPANTS There were 3147 boys (age: median = 14.9, SD = 1.8) who participated during adolescence in 1994 to 1995 (wave I), of whom 2353 were reinterviewed in 2008 (wave IV, age: median = 29.1, SD = 1.8). ASSESSMENT OF RISK FACTORS Football participation, history of psychological counseling, suicide ideation, and a suicide attempt in the past year during high school. MAIN OUTCOME MEASURES Lifetime history of depression, suicide ideation within the past year, and feeling depressed in the past 7 days at wave IV. RESULTS Men who played high school football, compared with those who did not, reported similar rates of lifetime diagnosis of depression, suicide ideation in the past year, and feeling depressed in the past 7 days. Those who played football reported similar rates of suicide ideation in the past year when they were in their early 20s. Individuals who underwent psychological counseling during adolescence were more likely to report a lifetime history of depression and suicide ideation in the past year. CONCLUSIONS Young men who played high school football are not at an increased risk for suicide ideation during both their early 20s and late 20s. By contrast, those who experienced mental health problems in high school were much more likely to experience suicide ideation during their 20s.
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Affiliation(s)
- Grant L Iverson
- Department of Physical Medicine and Rehabilitation, Harvard Medical School
- Spaulding Rehabilitation Hospital; Spaulding Research Institute
- MassGeneral Hospital for Children Sports Concussion Program; & Home Base, A Red Sox Foundation and Massachusetts General Hospital Program, Charlestown, Massachusetts
- Center for Health and Rehabilitation Research, Charlestown, Massachusetts; and
| | - Zachary C Merz
- Department of Physical Medicine and Rehabilitation, University of North Carolina at Chapel Hill, UNC Memorial Hospital, Chapel Hill, North Carolina
| | - Douglas P Terry
- Department of Physical Medicine and Rehabilitation, Harvard Medical School
- MassGeneral Hospital for Children Sports Concussion Program; & Home Base, A Red Sox Foundation and Massachusetts General Hospital Program, Charlestown, Massachusetts
- Center for Health and Rehabilitation Research, Charlestown, Massachusetts; and
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58
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Meliambro J, Karton C, Cournoyer J, Post A, Hoshizaki TB, Gilchrist MD. Comparison of head impact frequency and magnitude in youth tackle football and ice hockey. Comput Methods Biomech Biomed Engin 2021; 25:936-951. [PMID: 34615414 DOI: 10.1080/10255842.2021.1987420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Repetitive head impacts are a growing concern for youth and adolescent contact sport athletes as they have been linked to long term negative brain health outcomes. Of all contact sports, tackle football and ice hockey have been reported to have the highest incidence of head or brain injury however, each sporting environment is unique with distinct rules and regulations regarding contact and collisions. The purpose of this research was to measure and compare the head impact frequency and estimated magnitude of brain tissue strain, amongst youth tackle football and ice hockey players during game play. Head impact frequency was documented by video analysis of youth tackle football and ice hockey game play. Impact magnitude was determined through physical laboratory reconstructions and finite element modelling to estimate brain tissue strains. Tackle football demonstrated significantly higher impact frequency (P < 0.01) and magnitude of estimated brain tissue strains (P < 0.01) compared to ice hockey. A significantly higher number of higher strain head impacts were documented in tackle football when compared to ice hockey (P < 0.01). These differences suggest that youth football players may experience increased frequency and magnitude of estimated brain tissue strains in comparison to youth hockey.
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Affiliation(s)
- Julia Meliambro
- School of Human Kinetics, University of Ottawa, Ottawa, Canada
| | - Clara Karton
- School of Human Kinetics, University of Ottawa, Ottawa, Canada
| | - Janie Cournoyer
- School of Human Kinetics, University of Ottawa, Ottawa, Canada
| | - Andrew Post
- School of Human Kinetics, University of Ottawa, Ottawa, Canada.,School of Mechanical & Materials Engineering, University College Dublin, Dublin, Ireland
| | | | - Michael D Gilchrist
- School of Mechanical & Materials Engineering, University College Dublin, Dublin, Ireland
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59
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Levy Y, Bian K, Patterson L, Ouckama R, Mao H. Head Kinematics and Injury Metrics for Laboratory Hockey-Relevant Head Impact Experiments. Ann Biomed Eng 2021; 49:2914-2923. [PMID: 34472000 DOI: 10.1007/s10439-021-02855-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 08/17/2021] [Indexed: 01/04/2023]
Abstract
Investigating head responses during hockey-related blunt impacts and hence understanding how to mitigate brain injury risk from such impacts still needs more exploration. This study used the recently developed hockey helmet testing methodology, known as the Hockey Summation of Tests for the Analysis of Risk (Hockey STAR), to collect 672 laboratory helmeted impacts. Brain strains were then calculated from the according 672 simulations using the detailed Global Human Body Models Consortium (GHBMC) finite element head model. Experimentally measured head kinematics and brain strains were used to calculate head/brain injury metrics including peak linear acceleration, peak rotational acceleration, peak rotational velocity, Gadd Severity Index (GSI), Head Injury Criteria (HIC15), Generalized Acceleration Model for Brain Injury Threshold (GAMBIT), Brain Injury Criteria (BrIC), Universal Brain Injury Criterion (UBrIC), Diffuse Axonal Multi-Axis General Equation (DAMAGE), average maximum principal strain (MPS) and cumulative strain damage measure (CSDM). Correlation analysis of kinematics-based and strain-based metrics highlighted the importance of rotational velocity. Injury metrics that use rotational velocity correlated highly to average MPS and CSDM with UBrIC yielding the strongest correlation. In summary, a comprehensive analysis for kinematics-based and strain-based injury metrics was conducted through a hybrid experimental (672 impacts) and computational (672 simulations) approach. The results can provide references for adopting brain injury metrics when using the Hockey STAR approach and guide ice hockey helmet designs that help reduce brain injury risks.
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Affiliation(s)
- Yanir Levy
- School of Biomedical Engineering, Western University, 1151 Richmond St, London, ON, N6A 3K7, Canada
| | - Kewei Bian
- Department of Mechanical and Materials Engineering, Faculty of Engineering, Western University, 1151 Richmond St, London, ON, N6A 3K7, Canada
| | - Luke Patterson
- Department of Mechanical and Materials Engineering, Faculty of Engineering, Western University, 1151 Richmond St, London, ON, N6A 3K7, Canada
| | - Ryan Ouckama
- Bauer Hockey Ltd, 60 rue Jean-Paul Cayer, Blainville, Québec, J7C 0N9, Canada
| | - Haojie Mao
- School of Biomedical Engineering, Western University, 1151 Richmond St, London, ON, N6A 3K7, Canada. .,Department of Mechanical and Materials Engineering, Faculty of Engineering, Western University, 1151 Richmond St, London, ON, N6A 3K7, Canada.
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60
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Bayly PV, Alshareef A, Knutsen AK, Upadhyay K, Okamoto RJ, Carass A, Butman JA, Pham DL, Prince JL, Ramesh KT, Johnson CL. MR Imaging of Human Brain Mechanics In Vivo: New Measurements to Facilitate the Development of Computational Models of Brain Injury. Ann Biomed Eng 2021; 49:2677-2692. [PMID: 34212235 PMCID: PMC8516723 DOI: 10.1007/s10439-021-02820-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 06/22/2021] [Indexed: 01/04/2023]
Abstract
Computational models of the brain and its biomechanical response to skull accelerations are important tools for understanding and predicting traumatic brain injuries (TBIs). However, most models have been developed using experimental data collected on animal models and cadaveric specimens, both of which differ from the living human brain. Here we describe efforts to noninvasively measure the biomechanical response of the human brain with MRI-at non-injurious strain levels-and generate data that can be used to develop, calibrate, and evaluate computational brain biomechanics models. Specifically, this paper reports on a project supported by the National Institute of Neurological Disorders and Stroke to comprehensively image brain anatomy and geometry, mechanical properties, and brain deformations that arise from impulsive and harmonic skull loadings. The outcome of this work will be a publicly available dataset ( http://www.nitrc.org/projects/bbir ) that includes measurements on both males and females across an age range from adolescence to older adulthood. This article describes the rationale and approach for this study, the data available, and how these data may be used to develop new computational models and augment existing approaches; it will serve as a reference to researchers interested in using these data.
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Affiliation(s)
- Philip V Bayly
- Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, St. Louis, MO, USA.
| | - Ahmed Alshareef
- Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Andrew K Knutsen
- Center for Neuroscience and Regenerative Medicine, The Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Kshitiz Upadhyay
- Hopkins Extreme Materials Institute, Johns Hopkins University, Baltimore, MD, USA
| | - Ruth J Okamoto
- Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, St. Louis, MO, USA
| | - Aaron Carass
- Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - John A Butman
- Clinical Center, National Institutes of Health, Bethesda, MD, USA
| | - Dzung L Pham
- Center for Neuroscience and Regenerative Medicine, The Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Jerry L Prince
- Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - K T Ramesh
- Hopkins Extreme Materials Institute, Johns Hopkins University, Baltimore, MD, USA
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Curtis L Johnson
- Department of Biomedical Engineering, University of Delaware, Newark, DE, USA.
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Lee TA, Lycke RJ, Lee PJ, Cudal CM, Torolski KJ, Bucherl SE, Leiva-Molano N, Auerbach PS, Talavage TM, Nauman EA. Distribution of Head Acceleration Events Varies by Position and Play Type in North American Football. Clin J Sport Med 2021; 31:e245-e250. [PMID: 32032162 DOI: 10.1097/jsm.0000000000000778] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 06/19/2019] [Indexed: 02/02/2023]
Abstract
OBJECTIVE The goal of this pilot study was to evaluate the number of head acceleration events (HAEs) based on position, play type, and starting stance. DESIGN Prospective cohort study. SETTING Postcollegiate skill development camp during practice sessions and 1 exhibition game. PARTICIPANTS Seventy-eight male adult North American football athletes. INDEPENDENT VARIABLES A position was assigned to each participant, and plays in the exhibition game were separated by play type for analysis. During the exhibition game, video data were used to determine the effects of the starting position ("up" in a 2-point stance or "down" in a 3- or 4-point stance) on the HAEs experienced by players on the offensive line. MAIN OUTCOME MEASURES Peak linear acceleration and number of HAEs greater than 20 g (g = 9.81 m/s2) were measured using an xPatch (X2 Biosystems, Seattle, WA). RESULTS Four hundred thirty-seven HAEs were recorded during practices and 272 recorded during the exhibition game; 98 and 52 HAEs, the greatest number of HAEs by position in the game, were experienced by the offensive and defensive linemen, respectively. Linebackers and tight ends experienced high percentages of HAEs above 60 g. Offensive line players in a down stance had a higher likelihood of sustaining a HAE than players in an up stance regardless of the type of play (run vs pass). CONCLUSIONS Changing the stance of players on the offensive line and reducing the number of full-contact practices will lower HAEs.
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Affiliation(s)
- Taylor A Lee
- Department of Mechanical Engineering, Purdue University, West Lafayette, Indiana
| | - Roy J Lycke
- Department of Biomedical Engineering, Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana
| | - Patrick J Lee
- Department of Mechanical Engineering, Purdue University, West Lafayette, Indiana
| | - Caroline M Cudal
- Department of Biomedical Engineering, Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana
| | - Kelly J Torolski
- Department of Mechanical Engineering, Purdue University, West Lafayette, Indiana
| | - Sean E Bucherl
- Department of Biomedical Engineering, Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana
| | - Nicolas Leiva-Molano
- Department of Biomedical Engineering, Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana
| | - Paul S Auerbach
- Military/Emergency Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland
- Department of Emergency Medicine, Stanford University School of Medicine, Stanford, California
| | - Thomas M Talavage
- Department of Biomedical Engineering, Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana
- Department of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana; and
| | - Eric A Nauman
- Department of Mechanical Engineering, Purdue University, West Lafayette, Indiana
- Department of Biomedical Engineering, Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana
- Department of Basic Medical Sciences, Purdue University, West Lafayette, Indiana
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62
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Corbin-Berrigan LA, Wagnac É, Vinet SA, Charlebois-Plante C, Guay S, Beaumont LD. Head impacts in Canadian varsity football: an exploratory study. Concussion 2021; 6:CNC93. [PMID: 34408907 PMCID: PMC8369522 DOI: 10.2217/cnc-2020-0024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Accepted: 05/21/2021] [Indexed: 01/30/2023] Open
Affiliation(s)
- Laurie-Ann Corbin-Berrigan
- Département des sciences de l'activité physique, Université du Québec à Trois-Rivières, Trois-Rivières, QC, G9A 5H7, Canada.,Centre de recherche du CIUSSS du Nord-de-l'île de Montréal, Hôpital du Sacré-Coeur-de-Montréal, Montréal, QC, H4J 1C5, Canada
| | - Éric Wagnac
- Centre de recherche du CIUSSS du Nord-de-l'île de Montréal, Hôpital du Sacré-Coeur-de-Montréal, Montréal, QC, H4J 1C5, Canada.,Département de génie mécanique, École de Technologie Supérieure, Montréal, QC, H3C 1K3, Canada
| | - Sophie-Andrée Vinet
- Centre de recherche du CIUSSS du Nord-de-l'île de Montréal, Hôpital du Sacré-Coeur-de-Montréal, Montréal, QC, H4J 1C5, Canada.,Département de psychologie, Université de Montréal, Montréal, QC, H2V 2S9, Canada
| | - Camille Charlebois-Plante
- Centre de recherche du CIUSSS du Nord-de-l'île de Montréal, Hôpital du Sacré-Coeur-de-Montréal, Montréal, QC, H4J 1C5, Canada.,Département de psychologie, Université de Montréal, Montréal, QC, H2V 2S9, Canada
| | - Samuel Guay
- Centre de recherche du CIUSSS du Nord-de-l'île de Montréal, Hôpital du Sacré-Coeur-de-Montréal, Montréal, QC, H4J 1C5, Canada.,Département de psychologie, Université de Montréal, Montréal, QC, H2V 2S9, Canada
| | - Louis De Beaumont
- Centre de recherche du CIUSSS du Nord-de-l'île de Montréal, Hôpital du Sacré-Coeur-de-Montréal, Montréal, QC, H4J 1C5, Canada.,Département de chirurgie, Faculté de médecine, Université de Montréal, Montréal, QC, H3C 3J7, Canada
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63
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Kelley ME, Urban JE, Jones DA, Davenport EM, Miller LE, Snively BM, Powers AK, Whitlow CT, Maldjian JA, Stitzel JD. Analysis of longitudinal head impact exposure and white matter integrity in returning youth football players. J Neurosurg Pediatr 2021; 28:196-205. [PMID: 34130257 PMCID: PMC10193468 DOI: 10.3171/2021.1.peds20586] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 01/11/2021] [Indexed: 11/06/2022]
Abstract
OBJECTIVE The objective of this study was to characterize changes in head impact exposure (HIE) across multiple football seasons and to determine whether changes in HIE correlate with changes in imaging metrics in youth football players. METHODS On-field head impact data and pre- and postseason imaging data, including those produced by diffusion tensor imaging (DTI), were collected from youth football athletes with at least two consecutive seasons of data. ANCOVA was used to evaluate HIE variations (number of impacts, peak linear and rotational accelerations, and risk-weighted cumulative exposure) by season number. DTI scalar metrics, including fractional anisotropy, mean diffusivity, and linear, planar, and spherical anisotropy coefficients, were evaluated. A control group was used to determine the number of abnormal white matter voxels, which were defined as 2 standard deviations above or below the control group mean. The difference in the number of abnormal voxels between consecutive seasons was computed for each scalar metric and athlete. Linear regression analyses were performed to evaluate relationships between changes in HIE metrics and changes in DTI scalar metrics. RESULTS There were 47 athletes with multiple consecutive seasons of HIE, and corresponding imaging data were available in a subsample (n = 19) of these. Increases and decreases in HIE metrics were observed among individual athletes from one season to the next, and no significant differences (all p > 0.05) in HIE metrics were observed by season number. Changes in the number of practice impacts, 50th percentile impacts per practice session, and 50th percentile impacts per session were significantly positively correlated with changes in abnormal voxels for all DTI metrics. CONCLUSIONS These results demonstrate a significant positive association between changes in HIE metrics and changes in the numbers of abnormal voxels between consecutive seasons of youth football. Reducing the number and frequency of head impacts, especially during practice sessions, may decrease the number of abnormal imaging findings from one season to the next in youth football.
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Affiliation(s)
- Mireille E. Kelley
- Departments of Biomedical Engineering
- Virginia Tech–Wake Forest School of Biomedical Engineering and Sciences, Winston-Salem, North Carolina; and
| | - Jillian E. Urban
- Departments of Biomedical Engineering
- Virginia Tech–Wake Forest School of Biomedical Engineering and Sciences, Winston-Salem, North Carolina; and
| | - Derek A. Jones
- Departments of Biomedical Engineering
- Virginia Tech–Wake Forest School of Biomedical Engineering and Sciences, Winston-Salem, North Carolina; and
| | | | - Logan E. Miller
- Departments of Biomedical Engineering
- Virginia Tech–Wake Forest School of Biomedical Engineering and Sciences, Winston-Salem, North Carolina; and
| | | | | | - Christopher T. Whitlow
- Departments of Biomedical Engineering
- Radiology (Neuroradiology), and
- Clinical and Translational Sciences Institute, Wake Forest School of Medicine, Winston-Salem
| | - Joseph A. Maldjian
- Department of Radiology, University of Texas Southwestern, Dallas, Texas
| | - Joel D. Stitzel
- Departments of Biomedical Engineering
- Virginia Tech–Wake Forest School of Biomedical Engineering and Sciences, Winston-Salem, North Carolina; and
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Walter AE, Wilkes JR, Arnett PA, Miller SJ, Sebastianelli W, Seidenberg P, Slobounov SM. The accumulation of subconcussive impacts on cognitive, imaging, and biomarker outcomes in child and college-aged athletes: a systematic review. Brain Imaging Behav 2021; 16:503-517. [PMID: 34308510 DOI: 10.1007/s11682-021-00489-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/27/2021] [Indexed: 01/08/2023]
Abstract
Examine the effect of subconcussive impact accumulation on cognitive/functional, imaging, and biomarker outcomes over the course of a single season, specifically in contact sport athletes at collegiate level or younger. Systematic review following PRISMA guidelines and using Oxford Center for Evidence-Based Medicine 2011 Levels of Evidence and Newcastle Ottawa Assessment Scale. PubMed MEDLINE, PsycInfo, SPORT-Discus, Web of Science. Original research in English that addressed the influence of subconcussive impacts on outcomes of interest with minimum preseason and postseason measurement in current youth, high school, or college-aged contact sport athletes. 796 articles were initially identified, and 48 articles were included in this review. The studies mostly involved male football athletes in high school or college and demonstrated an underrepresentation of female and youth studies. Additionally, operationalization of previous concussion history and concussion among studies was very inconsistent. Major methodological differences existed across studies, with ImPACT and diffusion tensor imaging being the most commonly used modalities. Biomarker studies generally showed negative effects, cognitive/functional studies mostly revealed no effects, and advanced imaging studies showed generally negative findings over the season; however, there was variability in the findings across all types of studies. This systematic review revealed growing literature on this topic, but inconsistent methodology and operationalization across studies makes it challenging to draw concrete conclusions. Overall, cognitive measures alone do not seem to detect changes across this timeframe while imaging and biomarker measures may be more sensitive to changes following subconcussive impacts.
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Affiliation(s)
- Alexa E Walter
- Department of Kinesiology, Penn State University, 25 Recreation Hall, University Park, PA, 16802, USA.
| | - James R Wilkes
- Department of Kinesiology, Penn State University, 25 Recreation Hall, University Park, PA, 16802, USA
| | - Peter A Arnett
- Department of Psychology, Penn State University, University Park, PA, 16802, USA
| | - Sayers John Miller
- Department of Kinesiology, Penn State University, 25 Recreation Hall, University Park, PA, 16802, USA
| | - Wayne Sebastianelli
- Deparetment of Orthopaedics, Penn State Health, Milton S. Hershey Medical Center, Hershey, PA, 17033, USA
| | - Peter Seidenberg
- Department of Orthopaedics and Rehabilitation and Family and Community Medicine, Penn State Health, Milton S. Hershey Medical Center, Hershey, PA, 17033, USA
| | - Semyon M Slobounov
- Department of Kinesiology, Penn State University, 25 Recreation Hall, University Park, PA, 16802, USA
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65
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Kahriman A, Bouley J, Smith TW, Bosco DA, Woerman AL, Henninger N. Mouse closed head traumatic brain injury replicates the histological tau pathology pattern of human disease: characterization of a novel model and systematic review of the literature. Acta Neuropathol Commun 2021; 9:118. [PMID: 34187585 PMCID: PMC8243463 DOI: 10.1186/s40478-021-01220-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 06/18/2021] [Indexed: 12/15/2022] Open
Abstract
Traumatic brain injury (TBI) constitutes one of the strongest environmental risk factors for several progressive neurodegenerative disorders of cognitive impairment and dementia that are characterized by the pathological accumulation of hyperphosphorylated tau (p-Tau). It has been questioned whether mouse closed-head TBI models can replicate human TBI-associated tauopathy. We conducted longitudinal histopathological characterization of a mouse closed head TBI model, with a focus on pathological features reported in human TBI-associated tauopathy. Male C57BL/6 J mice were subjected to once daily TBI for 5 consecutive days using a weight drop paradigm. Histological analyses (AT8, TDP-43, pTDP-43, NeuN, GFAP, Iba-1, MBP, SMI-312, Prussian blue, IgG, βAPP, alpha-synuclein) were conducted at 1 week, 4 weeks, and 24 weeks after rTBI and compared to sham operated controls. We conducted a systematic review of the literature for mouse models of closed-head injury focusing on studies referencing tau protein assessment. At 1-week post rTBI, p-Tau accumulation was restricted to the corpus callosum and perivascular spaces adjacent to the superior longitudinal fissure. Progressive p-Tau accumulation was observed in the superficial layers of the cerebral cortex, as well as in mammillary bodies and cortical perivascular, subpial, and periventricular locations at 4 to 24 weeks after rTBI. Associated cortical histopathologies included microvascular injury, neuroaxonal rarefaction, astroglial and microglial activation, and cytoplasmatic localization of TDP-43 and pTDP-43. In our systematic review, less than 1% of mouse studies (25/3756) reported p-Tau using immunostaining, of which only 3 (0.08%) reported perivascular p-Tau, which is considered a defining feature of chronic traumatic encephalopathy. Commonly reported associated pathologies included neuronal loss (23%), axonal loss (43%), microglial activation and astrogliosis (50%, each), and beta amyloid deposition (29%). Our novel model, supported by systematic review of the literature, indicates progressive tau pathology after closed head murine TBI, highlighting the suitability of mouse models to replicate pertinent human histopathology.
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Affiliation(s)
- Aydan Kahriman
- Department of Neurology, Medical School, University of Massachusetts, 55 Lake Ave, Worcester, USA
| | - James Bouley
- Department of Neurology, Medical School, University of Massachusetts, 55 Lake Ave, Worcester, USA
| | - Thomas W Smith
- Department of Pathology, Medical School, University of Massachusetts, 55 Lake Ave, Worcester, USA
| | - Daryl A Bosco
- Department of Neurology, Medical School, University of Massachusetts, 55 Lake Ave, Worcester, USA
| | - Amanda L Woerman
- Department of Biology, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Nils Henninger
- Department of Neurology, Medical School, University of Massachusetts, 55 Lake Ave, Worcester, USA.
- Department of Psychiatry, Medical School, University of Massachusetts, 55 Lake Ave, Worcester, USA.
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66
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Should We Lose Sleep Over Sleep Disturbances After Sports-Related Concussion? A Scoping Review of the Literature. J Head Trauma Rehabil 2021; 37:E206-E219. [PMID: 34145161 DOI: 10.1097/htr.0000000000000701] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE A single, severe traumatic brain injury can result in chronic sleep disturbances that can persist several years after the incident. In contrast, it is unclear whether there are sleep disturbances after a sports-related concussion (SRC). Considering growing evidence of links between sleep disturbance and neurodegeneration, this review examined the potential links between diagnosed SRCs and sleep disturbances to provide guidance for future studies. METHODS The scoping review undertook a systematic search of key online databases (Scopus, MEDLINE, SportDiscus, and Web of Science) using predetermined search terms for any articles that examined sleep after concussion. A screening criterion using agreed inclusion and exclusion criteria was utilized to ensure inclusion of relevant articles. DESIGN This scoping review is guided by the PRSIMA Scoping Review report. RESULTS Ten studies met the inclusion criteria, reporting on 896 adults who had experienced an SRC. Comparison with 1327 non-SRC adults occurred in 8 studies. Nine studies subjectively examined sleep, of which all but one study reported sleep disturbances after an SRC. Three studies objectively measured sleep, with 2 studies indicating large coefficients of variation of sleep duration, suggesting a range of sleep responses after an SRC. The only study to examine overnight polysomnography showed no differences in sleep metrics between those with and without an SRC. No studies examined interventions to improve sleep outcomes in people with concussion. CONCLUSIONS This scoping review indicates preliminary evidence of sleep disturbances following an SRC. The heterogeneity of methodology used in the included studies makes consensus on the results difficult. Given the mediating role of sleep in neurodegenerative disorders, further research is needed to identify physiological correlates and pathological mechanisms of sleep disturbances in SRC-related neurodegeneration and whether interventions for sleep problems improve recovery from concussion and reduce the risk of SRC-related neurodegeneration.
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67
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Mazurkiewicz A, Xu S, Frei H, Banton R, Piehler T, Petel OE. Impact-Induced Cortical Strain Concentrations at the Sulcal Base and Its Implications for Mild Traumatic Brain Injury. J Biomech Eng 2021; 143:061015. [PMID: 33625494 DOI: 10.1115/1.4050283] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Indexed: 11/08/2022]
Abstract
This study investigated impact-induced strain fields within brain tissue surrogates having different cortical gyrification. Two elastomeric surrogates, one representative of a lissencephalic brain and the other of a gyrencephalic brain, were drop impacted in unison at four different heights and in two different orientations. Each surrogate contained a radiopaque speckle pattern that was used to calculate strain fields. Two different approaches, digital image correlation (DIC) and a particle tracking method, enabled comparisons of full-field and localized strain responses. The DIC results demonstrated increased localized deviations from the mean strain field in the surrogate with a gyrified cortex. Particle tracking algorithms, defining four-node quadrilateral elements, were used to investigate the differences in the strain response of three regions: the base of a sulcus, the adjacent gyrus, and the internal capsule of the surrogates. The results demonstrated that the strains in the cortex were concentrated at the sulcal base. This mechanical mechanism of increased strain is consistent with neurodegenerative markers observed in postmortem analyses, suggesting a potential mechanism of local damage due to strain amplification at the sulcal bases in gyrencephalic brains. This strain amplification mechanism may be responsible for cumulative neurodegeneration from repeated subconcussive impacts. The observed results suggest that lissencephalic animal models, such as rodents, would not have the same modes of injury present in a gyrencephalic brain, such as that of a human. As such, a shift toward representative mild traumatic brain injury animal models having gyrencephalic cortical structures should be strongly considered.
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Affiliation(s)
- Ashley Mazurkiewicz
- Department of Mechanical and Aerospace Engineering, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - Sheng Xu
- Department of Mechanical and Aerospace Engineering, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - Hanspeter Frei
- Department of Mechanical and Aerospace Engineering, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - Rohan Banton
- U.S. Army Research Laboratory, Aberdeen Proving Ground, Aberdeen, MD 21005-5066
| | - Thuvan Piehler
- U.S. Army Research Laboratory, Aberdeen Proving Ground, Aberdeen, MD 21005-5066; U.S. Army Medical Research and Development Command, Fort Detrick, MD 21702
| | - Oren E Petel
- Department of Mechanical and Aerospace Engineering, Carleton University, Ottawa, ON K1S 5B6, Canada
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Gozt AK, Hellewell SC, Thorne J, Thomas E, Buhagiar F, Markovic S, Van Houselt A, Ring A, Arendts G, Smedley B, Van Schalkwyk S, Brooks P, Iliff J, Celenza A, Mukherjee A, Xu D, Robinson S, Honeybul S, Cowen G, Licari M, Bynevelt M, Pestell CF, Fatovich D, Fitzgerald M. Predicting outcome following mild traumatic brain injury: protocol for the longitudinal, prospective, observational Concussion Recovery ( CREST) cohort study. BMJ Open 2021; 11:e046460. [PMID: 33986061 PMCID: PMC8126315 DOI: 10.1136/bmjopen-2020-046460] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
INTRODUCTION Mild traumatic brain injury (mTBI) is a complex injury with heterogeneous physical, cognitive, emotional and functional outcomes. Many who sustain mTBI recover within 2 weeks of injury; however, approximately 10%-20% of individuals experience mTBI symptoms beyond this 'typical' recovery timeframe, known as persistent post-concussion symptoms (PPCS). Despite increasing interest in PPCS, uncertainty remains regarding its prevalence in community-based populations and the extent to which poor recovery may be identified using early predictive markers. OBJECTIVE (1) Establish a research dataset of people who have experienced mTBI and document their recovery trajectories; (2) Evaluate a broad range of novel and established prognostic factors for inclusion in a predictive model for PPCS. METHODS AND ANALYSIS The Concussion Recovery Study (CREST) is a prospective, longitudinal observational cohort study conducted in Perth, Western Australia. CREST is recruiting adults aged 18-65 from medical and community-based settings with acute diagnosis of mTBI. CREST will create a state-wide research dataset of mTBI cases, with data being collected in two phases. Phase I collates data on demographics, medical background, lifestyle habits, nature of injury and acute mTBI symptomatology. In Phase II, participants undergo neuropsychological evaluation, exercise tolerance and vestibular/ocular motor screening, MRI, quantitative electroencephalography and blood-based biomarker assessment. Follow-up is conducted via telephone interview at 1, 3, 6 and 12 months after injury. Primary outcome measures are presence of PPCS and quality of life, as measured by the Post-Concussion Symptom Scale and the Quality of Life after Brain Injury questionnaires, respectively. Multivariate modelling will examine the prognostic value of promising factors. ETHICS AND DISSEMINATION Human Research Ethics Committees of Royal Perth Hospital (#RGS0000003024), Curtin University (HRE2019-0209), Ramsay Health Care (#2009) and St John of God Health Care (#1628) have approved this study protocol. Findings will be published in peer-reviewed journals and presented at scientific conferences. TRIAL REGISTRATION NUMBER ACTRN12619001226190.
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Affiliation(s)
- Aleksandra Karolina Gozt
- Curtin Health Innovation Research Institute, Curtin University Faculty of Health Sciences, Bentley, Western Australia, Australia
- Perron Institute of Neurological and Translational Science, Nedlands, Western Australia, Australia
| | - Sarah Claire Hellewell
- Curtin Health Innovation Research Institute, Curtin University Faculty of Health Sciences, Bentley, Western Australia, Australia
| | - Jacinta Thorne
- Curtin Health Innovation Research Institute, Curtin University Faculty of Health Sciences, Bentley, Western Australia, Australia
| | - Elizabeth Thomas
- Centre for Clinical Research Excellence, School of Population Health, Curtin University, Bentley, Western Australia, Australia
- Division of Surgery, Faculty of Health & Medical Sciences, The University of Western Australia, Crawley, Western Australia, Australia
| | - Francesca Buhagiar
- School of Psychological Science, The University of Western Australia, Crawley, Western Australia, Australia
| | - Shaun Markovic
- Australian Alzheimer's Research Foundation, Nedlands, Western Australia, Australia
- The Centre for Healthy Ageing, Health Futures Institute, Murdoch University, Murdoch, Western Australia, Australia
| | - Anoek Van Houselt
- School of Human Sciences, The University of Western Australia, Crawley, Western Australia, Australia
| | - Alexander Ring
- Institute for Immunology and Infectious Diseases, Murdoch University, Murdoch, Western Australia, Australia
- School of Physiotherapy and Exercise Science, Curtin University Faculty of Health Sciences, Bentley, Western Australia, Australia
| | - Glenn Arendts
- Emergency Department, Fiona Stanley Hospital, Murdoch, Western Australia, Australia
- Centre for Clinical Research in Emergency Medicine, Harry Perkins Institute of Medical Research, Nedlands, Western Australia, Australia
| | - Ben Smedley
- Emergency Department, Rockingham General Hospital, Cooloongup, Western Australia, Australia
| | - Sjinene Van Schalkwyk
- Emergency Department, Joondalup Health Campus, Joondalup, Western Australia, Australia
| | - Philip Brooks
- Emergency Department, Saint John of God Midland Public Hospital, Midland, Western Australia, Australia
- School of Medicine, The University of Notre Dame and Curtin Medical School, Curtin University, Perth, Western Australia, Australia
- Curtin Medical School, Curtin University, Bentley, Western Australia, Australia
| | - John Iliff
- Curtin Medical School, Curtin University, Bentley, Western Australia, Australia
- Emergency Department, Saint John of God Hospital Murdoch, Murdoch, Western Australia, Australia
- Emergency Department, Royal Perth Hospital, Perth, Western Australia, Australia
- Royal Flying Doctor Service- Western Operations, Jandakot, Western Australia, Australia
| | - Antonio Celenza
- Emergency Department, Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia
- Division of Emergency Medicine, School of Medicine, The University of Western Australia, Crawley, Western Australia, Australia
| | - Ashes Mukherjee
- Emergency Department, Armadale Health Service, Mount Nasura, Western Australia, Australia
| | - Dan Xu
- Centre for Clinical Research Excellence, School of Population Health, Curtin University, Bentley, Western Australia, Australia
- The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Suzanne Robinson
- Centre for Clinical Research Excellence, School of Population Health, Curtin University, Bentley, Western Australia, Australia
| | - Stephen Honeybul
- Statewide Director of Neurosurgery, Department of Health Government of Western Australia, Perth, Western Australia, Australia
- Head of Department, Sir Charles Gairdner Hospital, Royal Perth Hospital and Fiona Stanley Hospital, Perth, Western Australia, Australia
| | - Gill Cowen
- Curtin Medical School, Curtin University, Bentley, Western Australia, Australia
| | - Melissa Licari
- School of Human Sciences, The University of Western Australia, Crawley, Western Australia, Australia
- Telethon Kids Institute, West Perth, Western Australia, Australia
| | - Michael Bynevelt
- Division of Surgery, School of Medicine, The University of Western Australia, Crawley, Western Australia, Australia
- The Neurological Intervention & Imaging Service of Western Australia at Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia
| | - Carmela F Pestell
- Curtin Health Innovation Research Institute, Curtin University Faculty of Health Sciences, Bentley, Western Australia, Australia
- School of Psychological Science, The University of Western Australia, Crawley, Western Australia, Australia
| | - Daniel Fatovich
- Centre for Clinical Research in Emergency Medicine, Harry Perkins Institute of Medical Research, Nedlands, Western Australia, Australia
- Emergency Medicine, Royal Perth Hospital, The University of Western Australia, Perth, Western Australia, Australia
| | - Melinda Fitzgerald
- Curtin Health Innovation Research Institute, Curtin University Faculty of Health Sciences, Bentley, Western Australia, Australia
- Perron Institute of Neurological and Translational Science, Nedlands, Western Australia, Australia
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Champagne AA, Coverdale NS, Ross A, Murray C, Vallee I, Cook DJ. Characterizing changes in network connectivity following chronic head trauma in special forces military personnel: a combined resting-fMRI and DTI study. Brain Inj 2021; 35:760-768. [PMID: 33792439 DOI: 10.1080/02699052.2021.1906951] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
BACKGROUND Soldiers are exposed to significant repetitive head trauma, which may disrupt functional and structural brain connectivity patterns. PURPOSE/HYPOTHESIS Integrate resting-state functional MRI (rs-fMRI) and diffusion tensor imaging (DTI) to characterize changes in connectivity biomarkers within Canadian Special Operations Forces (CANSOF), hypothesizing that alterations in architectural organization of cortical hubs may follow chronic repetitive head trauma. METHODS Fifteen CANSOFs with a history of chronic exposure to sub-concussive head trauma and concussive injuries (1.9 ± 2.0 concussions (range: [0-6])), as well as an equal age-matched cohort of controls (CTLs) were recruited. BOLD-based rs-fMRI was combined with DTI to reconstruct functional and structural networks using independent component analyses and probabilistic tractography. Connectivity markers were computed based on the distance between functional seeds to assess for possible differences in injury susceptibility of short- and long-range connections. RESULTS/DISCUSSION Significant hyper- and hypo-connectivity differences in cortical connections were observed suggesting that chronic head trauma may predispose soldiers to changes in the functional organization of brain networks. Significant structural alterations in axonal fibers directly connecting disrupted functional nodes were specific to hyper-connected long-range connections, suggesting a potential relationship between axonal injury and increases in neural recruitment following repetitive head trauma from high-exposure military duties.
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Affiliation(s)
- Allen A Champagne
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, Canada.,School of Medicine, Queen's University, Kingston, ON, Canada
| | - Nicole S Coverdale
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, Canada
| | | | | | - Isabelle Vallee
- Canadian Special Operations Forces Command, Ottawa, ON, Canada
| | - Douglas J Cook
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, Canada.,Department of Surgery, Queen's University, Kingston, ON, Canada
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70
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Iverson GL, Van Patten R, Terry DP, Levi CR, Gardner AJ. Predictors and Correlates of Depression in Retired Elite Level Rugby League Players. Front Neurol 2021; 12:655746. [PMID: 33868156 PMCID: PMC8047059 DOI: 10.3389/fneur.2021.655746] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 03/10/2021] [Indexed: 12/14/2022] Open
Abstract
Background: There is considerable interest in determining whether later-in-life depression is associated with lifetime history of concussions or the duration of a career in professional contact and collision sports. Rugby league is a high-intensity collision sport involving a large number of tackles per game and a high rate of concussions. We examined predictors and correlates of depression in retired elite level rugby league players in Australia. Methods: Retired elite level rugby league players (N = 141, age: M = 52.6, SD = 13.8; Range = 30-89 years) completed the Depression, Anxiety, and Stress Scale (DASS), Brief Pain Inventory, Connor-Davidson Resilience Scale (CD-RISC), and Epworth Sleepiness Scale; they also reported on lifetime history of concussions. The DASS depression score was regressed on age, total number of self-reported concussions, years played professionally, CD-RISC score, BPI pain interference score, and ESS score. Results: The retired players reported a median of 15 total lifetime concussions [interquartile range (IQR) = 6-30], and a median of 8 years playing professional sports (IQR = 3.5-11). The proportion of the sample endorsing at least mild current depression was 29%. The DASS depression score was positively correlated with the DASS anxiety (r = 0.54) and DASS stress scores (r = 0.58). The CD-RISC score was negatively correlated with the depression score (r = -0.53). Depression scores were not significantly correlated with pain severity (r = 0.14), and were weakly correlated with life interference due to pain (r = 0.20) and years playing professional sports (r = -0.17). Depression scores were not significantly correlated with lifetime history of concussions (r = 0.14). A multiple regression model, with age, total number of self-reported concussions, years played professionally, the CD-RISC, Brief Pain Inventory-pain interference score, and Epworth Sleepiness Scale score as predictors was significant, with 35% of the variance in DASS depression accounted for. The two significant independent predictors of depression were lower resilience and greater life interference due to pain. Conclusions: This is the first large study of depression in retired rugby league players. Depression in these retired players was not meaningfully associated with lifetime history of concussions or number of years playing elite level collision sport. Depression was associated with current anxiety, stress, resilience, and life interference due to chronic pain.
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Affiliation(s)
- Grant L. Iverson
- Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, MA, United States
- Spaulding Rehabilitation Hospital, Charlestown, MA, United States
- Spaulding Research Institute, Charlestown, MA, United States
- MassGeneral Hospital for Children Sports Concussion Program, Boston, MA, United States
- Home Base, A Red Sox Foundation and Massachusetts General Hospital Program, Charlestown, MA, United States
| | - Ryan Van Patten
- Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, MA, United States
- Spaulding Rehabilitation Hospital, Charlestown, MA, United States
| | - Douglas P. Terry
- Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, MA, United States
- Spaulding Rehabilitation Hospital, Charlestown, MA, United States
- MassGeneral Hospital for Children Sports Concussion Program, Boston, MA, United States
- Home Base, A Red Sox Foundation and Massachusetts General Hospital Program, Charlestown, MA, United States
| | - Christopher R. Levi
- Sydney Partnership for Health, Education, Research and Enterprise (SPHERE), Sydney, NSW, Australia
- School of Medical Sciences, University of New South Wales, Randwick, NSW, Australia
- Priority Research Centre for Stroke and Brain Injury, School of Medicine and Public Health, University of Newcastle, Callaghan, NSW, Australia
- Hunter New England Local Health District Sports Concussion Program, Waratah, NSW, Australia
| | - Andrew J. Gardner
- Priority Research Centre for Stroke and Brain Injury, School of Medicine and Public Health, University of Newcastle, Callaghan, NSW, Australia
- Hunter New England Local Health District Sports Concussion Program, Waratah, NSW, Australia
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71
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Sullivan DR, Miller MW, Wolf EJ, Logue MW, Robinson ME, Fortier CB, Fonda JR, Wang DJ, Milberg WP, McGlinchey RE, Salat DH. Cerebral perfusion is associated with blast exposure in military personnel without moderate or severe TBI. J Cereb Blood Flow Metab 2021; 41:886-900. [PMID: 32580671 PMCID: PMC7983507 DOI: 10.1177/0271678x20935190] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Due to the use of improvised explosive devices, blast exposure and mild traumatic brain injury (mTBI) have become hallmark injuries of the Iraq and Afghanistan wars. Although the mechanisms of the effects of blast on human neurobiology remain active areas of investigation, research suggests that the cerebrovasculature may be particularly vulnerable to blast via molecular processes that impact cerebral blood flow. Given that recent work suggests that blast exposure, even without a subsequent TBI, may have negative consequences on brain structure and function, the current study sought to further understand the effects of blast exposure on perfusion. One hundred and eighty military personnel underwent pseudo-continuous arterial spin labeling (pCASL) imaging and completed diagnostic and clinical interviews. Whole-brain analyses revealed that with an increasing number of total blast exposures, there was significantly increased perfusion in the right middle/superior frontal gyri, supramarginal gyrus, lateral occipital cortex, and posterior cingulate cortex as well as bilateral anterior cingulate cortex, insulae, middle/superior temporal gyri and occipital poles. Examination of other neurotrauma and clinical variables such as close-range blast exposures, mTBI, and PTSD yielded no significant effects. These results raise the possibility that perfusion may be an important neural marker of brain health in blast exposure.
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Affiliation(s)
- Danielle R Sullivan
- National Center for PTSD, VA Boston Healthcare System, Boston, MA, USA.,Department of Psychiatry, Boston University School of Medicine, Boston, MA, USA
| | - Mark W Miller
- National Center for PTSD, VA Boston Healthcare System, Boston, MA, USA.,Department of Psychiatry, Boston University School of Medicine, Boston, MA, USA
| | - Erika J Wolf
- National Center for PTSD, VA Boston Healthcare System, Boston, MA, USA.,Department of Psychiatry, Boston University School of Medicine, Boston, MA, USA
| | - Mark W Logue
- National Center for PTSD, VA Boston Healthcare System, Boston, MA, USA.,Biomedical Genetics, Boston University School of Medicine, Boston, MA, USA.,Department of Biostatistics, Boston University School of Medicine, Boston, MA, USA
| | - Meghan E Robinson
- Core for Advanced MRI and Department of Neurosurgery, Baylor College of Medicine, Houston, TX, USA
| | - Catherine B Fortier
- Translational Research Center for TBI and Stress Disorders (TRACTS) and Geriatric Research, Educational and Clinical Center (GRECC), VA Boston Healthcare System, Boston, MA, USA.,Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Jennifer R Fonda
- Department of Psychiatry, Boston University School of Medicine, Boston, MA, USA.,Translational Research Center for TBI and Stress Disorders (TRACTS) and Geriatric Research, Educational and Clinical Center (GRECC), VA Boston Healthcare System, Boston, MA, USA.,Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Danny Jj Wang
- Laboratory of FMRI Technology (LOFT), Mark & Mary Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California, CA, USA.,Department of Neurology, University of Southern California, Los Angeles, CA, USA
| | - William P Milberg
- Translational Research Center for TBI and Stress Disorders (TRACTS) and Geriatric Research, Educational and Clinical Center (GRECC), VA Boston Healthcare System, Boston, MA, USA.,Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Regina E McGlinchey
- Translational Research Center for TBI and Stress Disorders (TRACTS) and Geriatric Research, Educational and Clinical Center (GRECC), VA Boston Healthcare System, Boston, MA, USA.,Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - David H Salat
- Translational Research Center for TBI and Stress Disorders (TRACTS) and Geriatric Research, Educational and Clinical Center (GRECC), VA Boston Healthcare System, Boston, MA, USA.,Neuroimaging Research for Veterans Center, VA Boston Healthcare System, Boston, MA, USA.,Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA
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72
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Saber M, Murphy SM, Cho Y, Lifshitz J, Rowe RK. Experimental diffuse brain injury and a model of Alzheimer's disease exhibit disease-specific changes in sleep and incongruous peripheral inflammation. J Neurosci Res 2021; 99:1136-1160. [PMID: 33319441 PMCID: PMC7897258 DOI: 10.1002/jnr.24771] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 11/18/2020] [Accepted: 11/24/2020] [Indexed: 01/09/2023]
Abstract
Elderly populations (≥65 years old) have the highest risk of developing Alzheimer's disease (AD) and/or obtaining a traumatic brain injury (TBI). Using translational mouse models, we investigated sleep disturbances and inflammation associated with normal aging, TBI and aging, and AD. We hypothesized that aging results in marked changes in sleep compared with adult mice, and that TBI and aging would result in sleep and inflammation levels similar to AD mice. We used female 16-month-old wild-type (WT Aged) and 3xTg-AD mice, as well as a 2-month-old reference group (WT Adult), to evaluate sleep changes. WT Aged mice received diffuse TBI by midline fluid percussion, and blood was collected from both WT Aged (pre- and post-TBI) and 3xTg-AD mice to evaluate inflammation. Cognitive behavior was tested, and tissue was collected for histology. Bayesian generalized additive and mixed-effects models were used for analyses. Both normal aging and AD led to increases in sleep compared with adult mice. WT Aged mice with TBI slept substantially more, with fragmented shorter bouts, than they did pre-TBI and compared with AD mice. However, differences between WT Aged and 3xTg-AD mice in immune cell populations and plasma cytokine levels were incongruous, cognitive deficits were similar, and cumulative sleep was not predictive of inflammation or behavior for either group. Our results suggest that in similarly aged individuals, TBI immediately induces more profound sleep alterations than in AD, although both diseases likely include cognitive impairments. Unique pathological sleep pathways may exist in elderly individuals who incur TBI compared with similarly aged individuals who have AD, which may warrant disease-specific treatments in clinical settings.
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Affiliation(s)
- Maha Saber
- BARROW Neurological Institute at Phoenix Children’s Hospital, Phoenix, AZ
- Department of Child Health, University of Arizona College of Medicine – Phoenix, Phoenix, AZ
| | - Sean M. Murphy
- Department of Child Health, University of Arizona College of Medicine – Phoenix, Phoenix, AZ
| | - Yerin Cho
- BARROW Neurological Institute at Phoenix Children’s Hospital, Phoenix, AZ
- Department of Child Health, University of Arizona College of Medicine – Phoenix, Phoenix, AZ
| | - Jonathan Lifshitz
- BARROW Neurological Institute at Phoenix Children’s Hospital, Phoenix, AZ
- Department of Child Health, University of Arizona College of Medicine – Phoenix, Phoenix, AZ
- Phoenix Veteran Affairs Health Care System, Phoenix, AZ
| | - Rachel K. Rowe
- BARROW Neurological Institute at Phoenix Children’s Hospital, Phoenix, AZ
- Department of Child Health, University of Arizona College of Medicine – Phoenix, Phoenix, AZ
- Phoenix Veteran Affairs Health Care System, Phoenix, AZ
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73
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Preseason Cerebrovascular Function in Adolescent Athletes. Ann Biomed Eng 2021; 49:2734-2746. [PMID: 33754253 DOI: 10.1007/s10439-021-02764-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 02/28/2021] [Indexed: 10/21/2022]
Abstract
The purpose of this study was to investigate the effects of sport participation, concussion history, and age of first exposure to football on preseason cerebrovascular function in adolescent athletes. Athletes (n = 53, age = 15.8 ± 1.2 years) were examined based on three exposure groupings: (1) sport participation (football vs. non-collision), (2) concussion history (none vs. ≥ 1), and (3) age of first exposure (football participants only). Transcranial Doppler assessed cerebrovascular reactivity (CVR) and neurovascular coupling (NVC), and separate independent samples t-tests evaluated group differences in CVR and NVC outcomes. Separate univariate linear regressions determined how age of first exposure related to CVR and NVC outcomes. Linear mixed effects models assessed group differences in CVR and NVC relative response curves. Differential response to NVC visual task response was significantly greater in non-collision sport athletes (F1,2946 = 38.69, p < 0.0001) and athletes without a concussion history (F1,2946 = 25.23, p < 0.0001). Older age of first exposure significantly predicted reduced breath-holding CVR response (F1,1560 = 2.92, p = 0.03). Healthy adolescent athletes have similar pre-season cerebrovascular function despite different sport participation and concussion history. However, age of first exposure may predict CVR in adolescent football athletes. Developmental literature identifies cerebrovascular function as dynamically changing throughout adolescence. Our study provides fundamental data informing the clinical meaningfulness of short- and long-term physiological function changes.
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74
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DeSimone JC, Davenport EM, Urban J, Xi Y, Holcomb JM, Kelley ME, Whitlow CT, Powers AK, Stitzel JD, Maldjian JA. Mapping default mode connectivity alterations following a single season of subconcussive impact exposure in youth football. Hum Brain Mapp 2021; 42:2529-2545. [PMID: 33734521 PMCID: PMC8090779 DOI: 10.1002/hbm.25384] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 02/09/2021] [Accepted: 02/10/2021] [Indexed: 12/14/2022] Open
Abstract
Repetitive head impact (RHI) exposure in collision sports may contribute to adverse neurological outcomes in former players. In contrast to a concussion, or mild traumatic brain injury, “subconcussive” RHIs represent a more frequent and asymptomatic form of exposure. The neural network‐level signatures characterizing subconcussive RHIs in youth collision‐sport cohorts such as American Football are not known. Here, we used resting‐state functional MRI to examine default mode network (DMN) functional connectivity (FC) following a single football season in youth players (n = 50, ages 8–14) without concussion. Football players demonstrated reduced FC across widespread DMN regions compared with non‐collision sport controls at postseason but not preseason. In a subsample from the original cohort (n = 17), players revealed a negative change in FC between preseason and postseason and a positive and compensatory change in FC during the offseason across the majority of DMN regions. Lastly, significant FC changes, including between preseason and postseason and between in‐ and off‐season, were specific to players at the upper end of the head impact frequency distribution. These findings represent initial evidence of network‐level FC abnormalities following repetitive, non‐concussive RHIs in youth football. Furthermore, the number of subconcussive RHIs proved to be a key factor influencing DMN FC.
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Affiliation(s)
- Jesse C. DeSimone
- Advanced Neuroscience Imaging Research (ANSIR) LaboratoryUniversity of Texas Southwestern Medical CenterDallasTexasUSA
- Department of RadiologyUniversity of Texas Southwestern Medical CenterDallasTexasUSA
| | - Elizabeth M. Davenport
- Advanced Neuroscience Imaging Research (ANSIR) LaboratoryUniversity of Texas Southwestern Medical CenterDallasTexasUSA
- Department of RadiologyUniversity of Texas Southwestern Medical CenterDallasTexasUSA
| | - Jillian Urban
- Department of Biomedical EngineeringWake Forest School of MedicineWinston SalemNorth CarolinaUSA
- Virginia Tech – Wake Forest School of Biomedical EngineeringWake Forest School of MedicineWinston SalemNorth CarolinaUSA
| | - Yin Xi
- Department of RadiologyUniversity of Texas Southwestern Medical CenterDallasTexasUSA
| | - James M. Holcomb
- Advanced Neuroscience Imaging Research (ANSIR) LaboratoryUniversity of Texas Southwestern Medical CenterDallasTexasUSA
- Department of RadiologyUniversity of Texas Southwestern Medical CenterDallasTexasUSA
| | - Mireille E. Kelley
- Department of Biomedical EngineeringWake Forest School of MedicineWinston SalemNorth CarolinaUSA
- Virginia Tech – Wake Forest School of Biomedical EngineeringWake Forest School of MedicineWinston SalemNorth CarolinaUSA
| | - Christopher T. Whitlow
- Virginia Tech – Wake Forest School of Biomedical EngineeringWake Forest School of MedicineWinston SalemNorth CarolinaUSA
- Department of Radiology – NeuroradiologyWake Forest School of MedicineWinston SalemNorth CarolinaUSA
- Clinical and Translational Sciences InstituteWake Forest School of MedicineWinston SalemNorth CarolinaUSA
| | - Alexander K. Powers
- Department of NeurosurgeryWake Forest School of MedicineWinston SalemNorth CarolinaUSA
| | - Joel D. Stitzel
- Department of Biomedical EngineeringWake Forest School of MedicineWinston SalemNorth CarolinaUSA
- Virginia Tech – Wake Forest School of Biomedical EngineeringWake Forest School of MedicineWinston SalemNorth CarolinaUSA
- Clinical and Translational Sciences InstituteWake Forest School of MedicineWinston SalemNorth CarolinaUSA
- Childress Institute for Pediatric TraumaWake Forest School of MedicineWinston SalemNorth CarolinaUSA
| | - Joseph A. Maldjian
- Advanced Neuroscience Imaging Research (ANSIR) LaboratoryUniversity of Texas Southwestern Medical CenterDallasTexasUSA
- Department of RadiologyUniversity of Texas Southwestern Medical CenterDallasTexasUSA
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75
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Iverson GL, Gardner AJ. Symptoms of traumatic encephalopathy syndrome are common in the US general population. Brain Commun 2021; 3:fcab001. [PMID: 33842882 PMCID: PMC8023423 DOI: 10.1093/braincomms/fcab001] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 11/04/2020] [Accepted: 11/19/2020] [Indexed: 12/14/2022] Open
Abstract
There are no validated criteria for diagnosing chronic traumatic encephalopathy, or traumatic encephalopathy syndrome, in a living person. The purpose of this study is to examine symptom reporting resembling the research criteria for traumatic encephalopathy syndrome in men and women from the US general population. This is a retrospective analysis of publicly available data from a cross-sectional epidemiological study. The National Comorbidity Survey Replication was designed to examine the prevalence and correlates of mental disorders in the USA. The study included a nationally representative sample of 9282 adults (4139 men and 5143 women). An in-person interview and survey were conducted in the homes of men and women from the general population. The study was conducted with participants residing in New York City, Los Angeles, Chicago, Philadelphia, Detroit, San Francisco, Washington DC, Dallas/Fort Worth, Houston, Boston, Nassau-Suffolk NY, St. Louis, Pittsburgh, Baltimore, Minneapolis and Atlanta. Symptoms from the research criteria for the diagnosis of traumatic encephalopathy syndrome were applied to men and women in the general population and in sub-groups of people with health problems and mental health problems. A small percentage of the US general population met symptom criteria for traumatic encephalopathy syndrome (6.6–11.9%, depending on the definition applied). People with chronic pain were much more likely to meet criteria (i.e. 14.8–30.5%), and two out of three people who have experienced suicidality in the past year met symptom criteria for traumatic encephalopathy syndrome (65.2–72.2%). The majority of women with a mood disorder and chronic pain met criteria (62.7–89.8%). This is the largest study, to date, examining the aspects of the research criteria for the diagnosis of traumatic encephalopathy syndrome in the general population, and the first study to examine these criteria in women. This study has important clinical and public health implications. The potential rate for misdiagnosing traumatic encephalopathy syndrome in adults who are experiencing chronic pain, idiopathic mental health problems or both is high.
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Affiliation(s)
- Grant L Iverson
- Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, MA 02115, USA.,Department of Physical Medicine and Rehabilitation, Spaulding Rehabilitation Hospital, Spaulding Research Institute, Charlestown, MA 02129, USA.,MassGeneral Hospital for Children Sports Concussion Program, Boston, MA 02114, USA.,Home Base, A Red Sox Foundation and Massachusetts General Hospital Program, Charlestown, MA 02129, USA
| | - Andrew J Gardner
- Hunter New England Local Health District, Sports Concussion Program, Waratah, NSW 2298, Australia.,Priority Research Centre for Sentre for Stroke and Brain Injury, School of Medicine and Public Health, University of Newcastle, Callaghan, NSW 2308, Australia
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76
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Repetitive Traumatic Brain Injury Causes Neuroinflammation before Tau Pathology in Adolescent P301S Mice. Int J Mol Sci 2021; 22:ijms22020907. [PMID: 33477535 PMCID: PMC7831108 DOI: 10.3390/ijms22020907] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 01/11/2021] [Accepted: 01/13/2021] [Indexed: 01/22/2023] Open
Abstract
Repetitive closed head injury (rCHI) is commonly encountered in young athletes engaged in contact and collision sports. Traumatic brain injury (TBI) including rCHI has been reported to be an important risk factor for several tauopathies in studies of adult humans and animals. However, the link between rCHI and the progression of tau pathology in adolescents remains to be elucidated. We evaluated whether rCHI can trigger the initial acceleration of pathological tau in adolescent mice and impact the long-term outcomes post-injury. To this end, we subjected adolescent transgenic mice expressing the P301S tau mutation to mild rCHI and assessed tau hyperphosphorylation, tangle formation, markers of neuroinflammation, and behavioral deficits at 40 days post rCHI. We report that rCHI did not accelerate tau pathology and did not worsen behavioral outcomes compared to control mice. However, rCHI induced cortical and hippocampal microgliosis and corpus callosum astrocytosis in P301S mice by 40 days post-injury. In contrast, we did not find significant microgliosis or astrocytosis after rCHI in age-matched WT mice or sham-injured P301S mice. Our data suggest that neuroinflammation precedes the development of Tau pathology in this rCHI model of adolescent repetitive mild TBI.
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77
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Heary RF, Majmundar N, Nagurka R. Is Youth Football Safe? An Analysis of Youth Football Head Impact Data. Neurosurgery 2021; 87:377-382. [PMID: 31993634 DOI: 10.1093/neuros/nyz563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 11/14/2019] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The issue of whether sports-related head trauma at the youth level can result in long-term sequelae that may negatively impact the participant has been widely debated. OBJECTIVE To investigate head impacts in the Summit Youth Football League equipped with helmets using the Riddell InSite impact monitoring system. The monitoring system allowed for analysis of the number of impacts and severity of impacts by player. METHODS Data were obtained for all 20 members of the youth football team. Impacts were recorded as "low," "medium," and "high" intensity. RESULTS All 20 players participated in all practices and games throughout the season. No player suffered a concussion throughout the entire season. There were 817 recorded impacts throughout the season. This was an average of 41 impacts per player over the course of the season and fewer than 4 impacts per player per week. Only one impact registered as "high." CONCLUSION We demonstrate that there are few head impacts over the course of an entire season at the middle school level. Guardian Caps, safe tackling techniques, and the age of participants may have contributed to the very low number of impacts recorded and the complete lack of injuries. This study only provides data demonstrating that youth football, when Guardian Caps and safe tackling techniques are enforced, does not appear to result in significant head impacts causing immediate head injuries. This study cannot comment on the safety of playing football at the collegiate or professional level.
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78
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Abstract
Due to the growing number of chronic traumatic encephalopathy (CTE) cases in the military and contact sports, defining the cellular and molecular substrate of this disorder is crucial. Most classic neuropathological investigations describe cortical tau and, to a lesser extent, amyloid lesions, which may underlie the clinical sequela associated with CTE. The application of modern molecular biologic technology to postmortem human brain tissue has made it possible to evaluate the genetic signature of specific neuronal phenotypes at different stages of CTE pathology. Most recently, molecular pathobiology has been used in the field of CTE, with an emphasis on the cholinergic neurons located within the nucleus basalis of Meynert, which develop tau pathology and are associated with cognitive dysfunction similar to that found in Alzheimer's disease (AD). Quantitative findings derived from single-cell transcript investigations provide clues to our understanding of the selective vulnerability of neurons containing AD-like tau pathology at different stages of CTE. Since human tissue-based studies provide a gold standard for the field of CTE, continued molecular pathological studies are needed to reveal novel drug targets for the treatment of this disorder.
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79
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Effect of subconcussive impacts on functional outcomes over a single collegiate football season. JOURNAL OF CONCUSSION 2020. [DOI: 10.1177/2059700220983165] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Context In collision sports, particularly American football, athletes can accumulate thousands of subconcussive impacts, or head acceleration events (HAEs), across a single season; however, the short-term consequences of these impacts are not well understood. Objective To investigate the effects of the accumulation of impacts during practices on cognitive functions over a single football season. Design Prospective observational study. Setting Athletic training room and University laboratory. Participants Twenty-three NCAA Football Bowl Subdivision players. Main outcome measures Helmet accelerometers during practices and virtual reality testing (VR; balance, reaction time, spatial memory) before and after the season. Results Preseason had the majority of ≥80 G impacts while during the season had the majority of ≥25 G to <80 G impacts and positional differences showed that linemen had the majority of both types. Virtual reality analysis revealed that scores significantly decreased after the season for spatial navigation ( p < 0.05) but not for balance or reaction time. Significant correlations ( p < 0.05) were found between cognitive measures and player demographic variables. Conclusions Even in the absence of clinical symptoms and concussion diagnosis, repetitive impacts may cause cognitive alterations. Documenting the distribution of impact quantity and intensity as a function of time and position may be considered by coaches and clinicians to reduce the accumulation of impacts in athletes exposed in contact sports.
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80
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Gallagher VT, Murthy P, Stocks J, Vesci B, Colegrove D, Mjaanes J, Chen Y, Breiter H, LaBella C, Herrold AA, Reilly JL. Differential Change in Oculomotor Performance among Female Collegiate Soccer Players versus Non-Contact Athletes from Pre- to Post-Season. Neurotrauma Rep 2020; 1:169-180. [PMID: 33274345 PMCID: PMC7703496 DOI: 10.1089/neur.2020.0051] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Sensitive and reliable tools are needed to evaluate potential behavioral and cognitive changes following head impact exposure in contact and collision sport participation. We evaluated change in oculomotor testing performance among female, varsity, collegiate athletes following variable exposure to head impacts across a season. Female, collegiate, contact sport (soccer, CONT) and non-contact sport (NON-CONT) athletes were assessed pre-season and post-season. Soccer athletes were grouped according to total season game headers into low dose (≤40 headers; CONT-Low Dose) or high dose (>40 headers; CONT-High Dose) groups. Performance on pro-saccade (reflexive visual response), anti-saccade (executive inhibition), and memory-guided saccade (MGS, spatial working memory) computer-based laboratory tasks were assessed. Primary saccade measures included latency/reaction time, inhibition error rate (anti-saccade only), and spatial accuracy (MGS only). NON-CONT (n = 20), CONT-Low Dose (n = 17), and CONT-High Dose (n = 7) groups significantly differed on pre-season versus post-season latency on tasks with executive functioning demands (anti-saccade and MGS, p ≤ 0.001). Specifically, NON-CONT and CONT-Low Dose demonstrated shorter (i.e., faster) anti-saccade (1.84% and 2.68%, respectively) and MGS (5.74% and 2.76%, respectively) latencies from pre-season to post-season, whereas CONT-High Dose showed 1.40% average longer anti-saccade, and 0.74% shorter MGS, latencies. NON-CONT and CONT-Low Dose demonstrated reduced (i.e., improved) inhibition error rate on the anti-saccade task at post-season versus pre-season, whereas CONT-High Dose demonstrated relative stability (p = 0.021). The results of this study suggest differential exposure to subconcussive head impacts in collegiate female athletes is associated with differential change in reaction time and inhibitory control performances on executive saccadic oculomotor testing.
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Affiliation(s)
- Virginia T Gallagher
- Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Prianka Murthy
- Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Jane Stocks
- Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Brian Vesci
- Department of Sports Medicine, Northwestern University, Evanston, Illinois, USA
| | - Danielle Colegrove
- Department of Sports Medicine, Northwestern University, Evanston, Illinois, USA
| | - Jeffrey Mjaanes
- Department of Sports Medicine, Northwestern University, Evanston, Illinois, USA
| | - Yufen Chen
- Center for Translational Imaging, Northwestern University, Chicago, Illinois, USA
| | - Hans Breiter
- Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Cynthia LaBella
- Division of Orthopedics and Sports Medicine, Ann and Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois, USA
| | - Amy A Herrold
- Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA.,Edward Hines, Jr. VA Hospital, Hines, Illinois, USA
| | - James L Reilly
- Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
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Iverson GL, Gardner AJ. Risk of Misdiagnosing Chronic Traumatic Encephalopathy in Men With Depression. J Neuropsychiatry Clin Neurosci 2020; 32:139-146. [PMID: 31587629 DOI: 10.1176/appi.neuropsych.19010021] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE In recent years, it has been proposed that depression represents one clinical subtype of chronic traumatic encephalopathy (CTE). This is the first study to examine the specificity of the research criteria for the clinical diagnosis of CTE in men with depression from the general population. METHODS Data from the National Comorbidity Survey Replication, an in-person survey that examined the prevalence and correlates of mental disorders in the United States, were used for this study. Men diagnosed as having a major depressive episode in the past 30 days were included (N=101; mean age=39.4 years, SD=12.9, range=18-71). They were deemed to meet research criteriafor CTE if they presented with the purported supportive clinical features of CTE (e.g., impulsivity and substance abuse, anxiety, apathy, suicidality, and headache). RESULTS Approximately half of the sample (52.5%) met the proposed research criteria for CTE (i.e., traumatic encephalopathy syndrome). If one accepts the delayed-onset criterion as being present, meaning that the men in the sample were presenting with depression years after retirement from sports or the military, then 83.2% of this sample would meet the research criteria for diagnosis. CONCLUSIONS The clinical problems attributed to CTE, such as depression, suicidality, anxiety, anger control problems, and headaches, co-occurred in this sample of men with depression from the general population-illustrating that these problems are not specific or unique to CTE. More research is needed to determine whether depression is, in fact, a clinical subtype of CTE.
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Affiliation(s)
- Grant L Iverson
- The Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston (Iverson); Spaulding Rehabilitation Hospital and Spaulding Research Institute, Boston (Iverson); the Sports Concussion Program, MassGeneral Hospital for Children, Boston (Iverson); Home Base, A Red Sox Foundation and Massachusetts General Hospital Program, Boston (Iverson); the Sports Concussion Program, Hunter New England Local Health District, New South Wales, Australia (Gardner); and the Centre for Stroke and Brain Injury, School of Medicine and Public Health, University of Newcastle, Callaghan, New South Wales, Australia (Gardner)
| | - Andrew J Gardner
- The Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston (Iverson); Spaulding Rehabilitation Hospital and Spaulding Research Institute, Boston (Iverson); the Sports Concussion Program, MassGeneral Hospital for Children, Boston (Iverson); Home Base, A Red Sox Foundation and Massachusetts General Hospital Program, Boston (Iverson); the Sports Concussion Program, Hunter New England Local Health District, New South Wales, Australia (Gardner); and the Centre for Stroke and Brain Injury, School of Medicine and Public Health, University of Newcastle, Callaghan, New South Wales, Australia (Gardner)
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82
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Johnson B, Dodd A, Mayer AR, Hallett M, Slobounov S. Are there any differential responses to concussive injury in civilian versus athletic populations: a neuroimaging study. Brain Imaging Behav 2020; 14:110-117. [PMID: 30361946 DOI: 10.1007/s11682-018-9982-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Accurate identification and classification of patients suffering from mild traumatic brain injury (mTBI) is a significant challenge faced by clinicians and researchers. To examine if there are different pathophysiological responses to concussive injury in different populations, evaluated here comparing collegiate athletes versus age-matched non-athletes. Resting-state fMRI data were acquired in the acute phase of concussion from 30 collegiate athletes and from 30 injury and age matched non-athletes. Resting-state functional connectivity measures revealed group differences with reduced connectivity in the anterior cingulate cortex (p < .05) and posterior cingulate cortex (p < 0.05) hubs of the Default Mode Network in the athletes. Given the known positive effects of exercise on brain functional reserves and neural efficiency concept, we expected less pronounced effect of concussion in athletic population. In contrast, there were significant decreases in functional connectivity in athletes that could be a result of previous repetitive subconcussive impacts and history of concussion.
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Affiliation(s)
- Brian Johnson
- Department of Kinesiology, The Pennsylvania State University, 276, Recreation Building, University Park, PA, 16802, USA
| | - Andrew Dodd
- The Mind Research Network and Lovelace Biomedical and Environmental Research Institute, Albuquerque, NM, USA
| | - Andrew R Mayer
- The Mind Research Network and Lovelace Biomedical and Environmental Research Institute, Albuquerque, NM, USA.,Departments of Neurology and Psychiatry, University of New Mexico School of Medicine, Albuquerque, NM, USA
| | - Mark Hallett
- National Institutes of Health, National Institute of Neurological Disorders and Stroke, Bethesda, MD, 20892, USA
| | - Semyon Slobounov
- Department of Kinesiology, The Pennsylvania State University, 276, Recreation Building, University Park, PA, 16802, USA. .,Department of Neurosurgery, Penn State Milton S. Hershey Medical Center, Hershey, PA, 17033, USA.
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83
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Lee T, Lycke R, Auger J, Music J, Dziekan M, Newman S, Talavage T, Leverenz L, Nauman E. Head acceleration event metrics in youth contact sports more dependent on sport than level of play. Proc Inst Mech Eng H 2020; 235:208-221. [PMID: 33183139 DOI: 10.1177/0954411920970812] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The goal of the study was to evaluate how repetitive head traumas sustained by athletes in contact sports depend on sport and level of play. A total of 16 middle school football players, 107 high school football players, and 65 high school female soccer players participated. Players were separated into levels of play: middle school (MS), freshman (FR), junior varsity (JV), junior varsity-varsity (JV-V), and varsity (V). xPatch sensors were used to measure peak translational and angular accelerations (PTA and PAA, respectively) for each head acceleration event (HAE) during practice and game sessions. Data were analyzed using a custom MATLAB program to compare metrics that have been correlated with functional neurological changes: session metrics (median HAEs per contact session), season metrics (total HAEs, cumulative PTA/PAA), and regressions (cumulative PTA/PAA versus total HAEs, total HAEs versus median HAEs per contact session). Football players had greater session (p<.001) and season (p<.001) metrics than soccer players, but soccer players had a significantly greater player average PAA per HAE than football players (p<.001). Middle school football players had similar session and season metrics to high school level athletes. In conclusion, sport has a greater influence on HAE characteristics than level of play.
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Affiliation(s)
- Taylor Lee
- School of Mechanical Engineering, Purdue University, West Lafayette, IN, USA
| | - Roy Lycke
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| | - Joshua Auger
- School of Mechanical Engineering, Purdue University, West Lafayette, IN, USA
| | - Jacob Music
- School of Mechanical Engineering, Purdue University, West Lafayette, IN, USA
| | - Michael Dziekan
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| | - Sharlene Newman
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, USA
| | - Thomas Talavage
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA.,Department of Electrical and Computer Engineering, Purdue University, West Lafayette, IN, USA
| | - Larry Leverenz
- Department of Health and Kinesiology, Purdue University, West Lafayette, IN, USA
| | - Eric Nauman
- School of Mechanical Engineering, Purdue University, West Lafayette, IN, USA.,Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA.,Department of Basic Medical Sciences, Purdue University, West Lafayette, IN, USA
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84
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Raymont V, Thayanandan T. What do we know about the risks of developing dementia after traumatic brain injury? Minerva Med 2020; 112:288-297. [PMID: 33164474 DOI: 10.23736/s0026-4806.20.07084-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Traumatic brain injury (TBI) is a risk factor for the later development of dementia, but although the evidence dates back to the early 20th century, the nature of any association and its mechanistic pathways remain unclear. There has been greater focus on this subject over recent years, in part because of increasing reports around sports related TBIs, especially in the USA. Differences in research methods and clinical sampling remain the primary reason for the variable findings, although there is clearly increased prevalence of neurodegenerative disorders in general. Duration of follow up, definition of both TBI and dementia, and differences in the extent to which other dementia risk factors are controlled, as well as concerns about medical record accuracy are all issues yet to be resolved in TBI research, as is an absence pathological evidence. In addition, TBI has been reported to initiate a cascade of pathological processes related to several neurodegenerative disorders, and as such, it is likely that the risks vary between individuals. Given the evidence that dementia risk may increase with injury severity and frequency, a detailed account of age and type of injury, as well as lifetime TBI exposure is essential to document in future studies, and further longitudinal research with biomarker assessments are needed.
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Affiliation(s)
- Vanessa Raymont
- Department of Psychiatry, Warneford Hospital, University of Oxford, Oxford, UK -
| | - Tony Thayanandan
- Department of Psychiatry, Warneford Hospital, University of Oxford, Oxford, UK
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85
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Merz ZC, Flashman LA, Ford JC, McDonald BC, McAllister TW. Comparison of season-long diffusivity measures in a cohort of non-concussed contact and non-contact athletes. J Clin Exp Neuropsychol 2020; 42:811-821. [PMID: 32893734 PMCID: PMC7572734 DOI: 10.1080/13803395.2020.1813257] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 08/14/2020] [Indexed: 12/14/2022]
Abstract
INTRODUCTION Concern surrounding short- and long-term consequences of participation in contact sports has become a significant public health topic. Previous literature utilizing diffusion tensor imaging in sports-related concussion has exhibited notable variety of analysis methods and analyzed regions of interest, and largely focuses on acute effects of concussion. The current study aimed to compare diffusivity metrics across a single season within athlete cohorts with no history of concussion. METHODS A prospective cohort of 75 contact and 79 non-contact division I athletes were compared across diffusion tensor imaging metrics (i.e. TRACULA); examinations were also performed assessing the relationship between neuroimaging metrics, head impact exposure metrics (in-helmet accelerometer), and neurocognitive variables. Assessment occurred at pre-and post-season time points. RESULTS Seasonal changes in fractional anisotropy and mean diffusivity values did not differ between athlete cohorts, nor did they differ within cohort groups, across pre- and post-season scans. Specific to contact athletes, positive associations were found between uncinate fasciculus mean diffusivity values and season linear acceleration (p =.018), season rotational acceleration (p =.017), and season hit severity (p =.021). CONCLUSIONS Results suggest an influence of impact frequency, type, and severity on white matter integrity in select brain regions in contact athletes. Current findings expand our knowledge of anatomical changes over the course of a single season, and underscore the importance of considering methodology when interpreting findings in this population, as differing image analysis techniques may lead to different conclusions regarding significant effects.
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Affiliation(s)
- Zachary C Merz
- LeBauer Department of Neurology, Moses H. Cone Memorial Hospital , Greensboro, NC, USA
| | - Laura A Flashman
- Department of Neurology, Wake Forest Baptist Health, Wake Forest University , Winston-Salem, NC, USA
| | - James C Ford
- Department of Psychiatry, Dartmouth-Hitchcock Medical Center and Geisel School of Medicine at Dartmouth , Hanover, NH, USA
| | - Brenna C McDonald
- Department of Radiology and Imaging Sciences, Indiana University School of Medicine , Indianapolis, IN, USA
| | - Thomas W McAllister
- Department of Psychiatry, Indiana University School of Medicine , Indianapolis, IN, USA
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86
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Rawlings S, Takechi R, Lavender AP. Effects of sub-concussion on neuropsychological performance and its potential mechanisms: A narrative review. Brain Res Bull 2020; 165:56-62. [PMID: 33011196 DOI: 10.1016/j.brainresbull.2020.09.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 09/12/2020] [Accepted: 09/25/2020] [Indexed: 12/12/2022]
Abstract
Concussion and mild traumatic brain injury (mTBI) are recognised as serious medical events that are relatively common in contact sports. Recently, the seemingly non-injurious phenomenon of sub-concussion has gained interest among neuroscience researchers and early studies are showing that there may be some acute and chronic effects on brain health and function with repeated sub-concussive events of the type seen in soccer, where players strike the ball with the head, and collision sports like the rugby codes. The aim of this narrative review is to describe sub-concussion and the current understanding of short and long term effects of repeated minor impacts that have been found to occur in human and animal models. Here, potential mechanisms for cognitive dysfunction following sub-concussion and recommend directions for future research are discussed. The Potential mechanisms of injuries resulting from sub-concussion such as changes in blood brain barrier integrity, neuroinflammation, cognitive impairment, and oxidative stress damage, among other changes in central nervous system function vary considerably making understanding of the underlying causative mechanism challenging for researchers. Some evidence suggests a link between impaired cerebrovascular function and cognitive impairment which poses a potential mechanism linking the two. It is hoped that this review helps guide researchers toward a potential direction of investigations.
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Affiliation(s)
- Samuel Rawlings
- School of Physiotherapy and Exercise Science, Faculty of Health Sciences, Curtin University, Perth, Australia
| | - Ryusuke Takechi
- Curtin Health Innovation Research Institute, Curtin University, Perth, Australia; School of Public Health, Faculty of Health Sciences, Curtin University, Perth, Australia
| | - Andrew P Lavender
- School of Physiotherapy and Exercise Science, Faculty of Health Sciences, Curtin University, Perth, Australia; School of Science, Psychology and Sport, Federation University Australia, Ballarat, Australia.
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87
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Iverson GL. Retired National Football League Players are Not at Greater Risk for Suicide. Arch Clin Neuropsychol 2020; 35:332-341. [PMID: 31665203 PMCID: PMC7297280 DOI: 10.1093/arclin/acz023] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Revised: 03/28/2019] [Accepted: 04/29/2019] [Indexed: 12/14/2022] Open
Abstract
Objective Some researchers have claimed that former National Football League (NFL) players are at increased risk for suicide as a clinical feature of chronic traumatic encephalopathy (CTE). This review examines the literature on risk for suicide in former professional football players, and the association between suicide and CTE. Method A narrative review of the literature published between 1928 and 2018. Results Between 1928 and 2009, suicide was not considered to be a clinical feature of CTE in the literature. The best available evidence from epidemiological studies suggests that former NFL football players are at lesser risk for suicide, not greater risk, compared to men in the general population. However, surveys have revealed that a substantial minority of former NFL players have depression and other mental health problems, chronic pain and opioid use is relatively common, and those with depression and chronic pain also have greater life stress and financial difficulties. That minority would be at increased risk for suicidal thoughts and behaviors. Conclusions Researchers and clinicians are encouraged to be cautious and circumspect when considering the clinical presentation of former athletes, and to not assume that depression and suicidality are caused by specific types of neuropathology. This represents a reductionistic and Procrustean view. Some former football players have mental health problems, but it should not be assumed uncritically that the underlying cause is an inexorably progressive neurodegenerative disease. Providing evidence-informed and evidence-supported treatments for depression and suicidality might reduce suffering and improve their functioning.
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Affiliation(s)
- Grant L Iverson
- Department of Physical Medicine and Rehabilitation, Harvard Medical School; Spaulding Rehabilitation Hospital; MassGeneral Hospital for Children Sport Concussion Program; & Home Base, A Red Sox Foundation and Massachusetts General Hospital Program, Boston, MA, USA
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88
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Baker HP, Volchenko E, Athiviraham A. Does the MLB's collision at home plate rule change prevent concussion injuries in catchers? PHYSICIAN SPORTSMED 2020; 48:354-357. [PMID: 31961751 DOI: 10.1080/00913847.2020.1718565] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Background: In 2013, appropriate conduct of both the catcher and baserunner at the home plate was outlined with the addition of rule 7.13. This new rule was mandated in order to protect athletes from 'egregious' collisions at the home plate. The aims of this study were to quantify the impact of the Collision at Home Plate rule on concussion rates among MLB catchers, and time spent on the DL with concussion symptoms, before and after rule 7.13 was officially enacted (2012-2013, 2015-2016). Hypothesis: We hypothesized that the rate of concussions suffered by MLB catchers would be significantly lower after the enactment of rule 7.13 and that there would be no significant difference in time spent on the DL between the two cohorts. Study design: Retrospective Cohort Level of evidence: Level 3 Methods: The data was compiled using publicly available information extracted from MLB transactions. All MLB catchers placed on the DL for a concussion injury from 2012 to 2013 and 2015 to 2016 were included in this study. Relative risk (with 95% CI) was calculated by using the number of injuries per 1,0000 athletic exposures for the 2 seasons under the rule change (2015-2016) versus the previous 2 seasons (2012-2013). Results: Among catchers the relative risk of concussion per 1000 athletic exposures was 0.31 (95% CI, 0.11-0.85) when comparing the 2 seasons after the introduction of rule 7.13 (2015, 2016) versus the 2 seasons before (2012, 2013). There was no significant statistical difference in average time catchers spent on the DL for concussion injuries when comparing the 2012 and 2013 seasons versus 2015 and 2016. Conclusions: The MLB's rule limiting home plate collisions significantly reduced the number of concussions suffered by MLB catchers. Clinical relevance: This study provides important insight regarding patterns and injury rates in professional baseball catchers and can serve as a benchmark for discussion about injury prevention in players of this position. To our knowledge, no other study has focused on rule 7.13 and its effect on concussion rates in MLB catchers.
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Affiliation(s)
- Hayden P Baker
- Department of Orthopaedic Surgery, The University of Chicago , Chicago, IL, USA
| | - Elan Volchenko
- College of Medicine, The University of Illinois , Chicago, IL, USA
| | - Aravind Athiviraham
- Department of Orthopaedic Surgery, The University of Chicago , Chicago, IL, USA
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89
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Ardila A, Lahiri D. Executive dysfunction in COVID-19 patients. Diabetes Metab Syndr 2020; 14:1377-1378. [PMID: 32755837 PMCID: PMC7373676 DOI: 10.1016/j.dsx.2020.07.032] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 07/10/2020] [Accepted: 07/17/2020] [Indexed: 12/14/2022]
Affiliation(s)
- Alfredo Ardila
- Psychology Doctoral Program, Albizu University, Miami, FL, USA; I.M. Sechenov First Moscow State Medical University, Moscow, Russia.
| | - Durjoy Lahiri
- Bangur Institute of Neurosciences, Institute of Post Graduate Medical Education and Research, Kolkata, India
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90
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Tierney GJ, Kuo C, Wu L, Weaving D, Camarillo D. Analysis of head acceleration events in collegiate-level American football: A combination of qualitative video analysis and in-vivo head kinematic measurement. J Biomech 2020; 110:109969. [DOI: 10.1016/j.jbiomech.2020.109969] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 05/28/2020] [Accepted: 07/20/2020] [Indexed: 11/29/2022]
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91
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Green TRF, Ortiz JB, Wonnacott S, Williams RJ, Rowe RK. The Bidirectional Relationship Between Sleep and Inflammation Links Traumatic Brain Injury and Alzheimer's Disease. Front Neurosci 2020; 14:894. [PMID: 32982677 PMCID: PMC7479838 DOI: 10.3389/fnins.2020.00894] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 07/31/2020] [Indexed: 12/18/2022] Open
Abstract
Traumatic brain injury (TBI) and Alzheimer's disease (AD) are diseases during which the fine-tuned autoregulation of the brain is lost. Despite the stark contrast in their causal mechanisms, both TBI and AD are conditions which elicit a neuroinflammatory response that is coupled with physical, cognitive, and affective symptoms. One commonly reported symptom in both TBI and AD patients is disturbed sleep. Sleep is regulated by circadian and homeostatic processes such that pathological inflammation may disrupt the chemical signaling required to maintain a healthy sleep profile. In this way, immune system activation can influence sleep physiology. Conversely, sleep disturbances can exacerbate symptoms or increase the risk of inflammatory/neurodegenerative diseases. Both TBI and AD are worsened by a chronic pro-inflammatory microenvironment which exacerbates symptoms and worsens clinical outcome. Herein, a positive feedback loop of chronic inflammation and sleep disturbances is initiated. In this review, the bidirectional relationship between sleep disturbances and inflammation is discussed, where chronic inflammation associated with TBI and AD can lead to sleep disturbances and exacerbated neuropathology. The role of microglia and cytokines in sleep disturbances associated with these diseases is highlighted. The proposed sleep and inflammation-mediated link between TBI and AD presents an opportunity for a multifaceted approach to clinical intervention.
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Affiliation(s)
- Tabitha R. F. Green
- BARROW Neurological Institute at Phoenix Children’s Hospital, Phoenix, AZ, United States
- Department of Child Health, University of Arizona College of Medicine – Phoenix, Phoenix, AZ, United States
| | - J. Bryce Ortiz
- BARROW Neurological Institute at Phoenix Children’s Hospital, Phoenix, AZ, United States
- Department of Child Health, University of Arizona College of Medicine – Phoenix, Phoenix, AZ, United States
| | - Sue Wonnacott
- Department of Biology and Biochemistry, University of Bath, Bath, United Kingdom
| | - Robert J. Williams
- Department of Biology and Biochemistry, University of Bath, Bath, United Kingdom
| | - Rachel K. Rowe
- BARROW Neurological Institute at Phoenix Children’s Hospital, Phoenix, AZ, United States
- Department of Child Health, University of Arizona College of Medicine – Phoenix, Phoenix, AZ, United States
- Phoenix Veteran Affairs Health Care System, Phoenix, AZ, United States
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92
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Iverson GL, Gardner AJ. Risk for Misdiagnosing Chronic Traumatic Encephalopathy in Men With Anger Control Problems. Front Neurol 2020; 11:739. [PMID: 32849206 PMCID: PMC7399643 DOI: 10.3389/fneur.2020.00739] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Accepted: 06/16/2020] [Indexed: 12/14/2022] Open
Abstract
Background: There are no validated or agreed upon criteria for diagnosing chronic traumatic encephalopathy (CTE) in a living person. In recent years, it has been proposed that anger dyscontrol represents a behavioral clinical phenotype of CTE. This is the first study to examine the specificity of the diagnostic research criteria for traumatic encephalopathy syndrome (TES, the clinical condition proposed to be CTE) in men from the US general population who have anger dyscontrol problems. It was hypothesized that a substantial percentage of these men would meet the research criteria for TES. Methods: Data from 4,139 men who participated in the National Comorbidity Survey Replication, an in-person survey that examined the prevalence and correlates of mental disorders in the United States, were included in this study. Men who were diagnosed with intermittent explosive disorder in the past year were the clinical sample of interest (n = 206; 5.0% of all men in the database), and the remaining men were used as a comparison sample. They were classified as meeting the research criteria for TES if they presented with the purported supportive clinical features of CTE (e.g., impulsivity/substance abuse, anxiety, apathy, suicidality, headache). Results: In this sample of men from the general population with intermittent explosive disorder, 27.3% met a conservative definition of the proposed research criteria for CTE (i.e., traumatic encephalopathy syndrome). If one assumes the delayed-onset criterion is present, meaning that the men in the sample are compared to former athletes or military veterans presenting with mental health problems years after retirement, then 65.0% of this sample would meet the research criteria for TES. Conclusions: These results have important implications. Using conservative criteria, at least one in four men from the general population, who have serious anger control problems, will meet the symptom criteria for TES. If one considers former athletes and military veterans with anger control problems who present many years after retirement and who experienced a documented decline in their mental health, nearly two-thirds will meet these research criteria. More research is needed to examine risks for misdiagnosing TES and to determine whether anger dyscontrol is a clinical phenotype of CTE.
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Affiliation(s)
- Grant L Iverson
- Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, MA, United States.,Spaulding Rehabilitation Hospital and Spaulding Research Institute, Charlestown, MA, United States.,MassGeneral Hospital for Children™ Sport Concussion Program, Boston, MA, United States.,Home Base, A Red Sox Foundation and Massachusetts General Hospital Program, Charlestown, MA, United States
| | - Andrew J Gardner
- Hunter New England Local Health District, Sports Concussion Program, Newcastle, NSW, Australia.,Priority Research Centre for Stroke and Brain Injury, School of Medicine and Public Health, University of Newcastle, Newcastle, NSW, Australia
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93
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Champagne AA, Coverdale NS, Germuska M, Bhogal AA, Cook DJ. Changes in volumetric and metabolic parameters relate to differences in exposure to sub-concussive head impacts. J Cereb Blood Flow Metab 2020; 40:1453-1467. [PMID: 31307284 PMCID: PMC7308522 DOI: 10.1177/0271678x19862861] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 06/11/2019] [Indexed: 01/15/2023]
Abstract
Structural and calibrated magnetic resonance imaging data were acquired on 44 collegiate football players prior to the season (PRE), following the first four weeks in-season (PTC) and one month after the last game (POST). Exposure data collected from g-Force accelerometers mounted to the helmet of each player were used to split participants into HIGH (N = 22) and LOW (N = 22) exposure groups, based on the frequency of impacts sustained by each athlete. Significant decreases in grey-matter volume specific to the HIGH group were documented at POST (P = 0.009), compared to baseline. Changes in resting cerebral blood flow (CBF0), corrected for partial volume effects, were observed within the HIGH group, throughout the season (P < 0.0001), suggesting that alterations in perfusion may follow exposure to sub-concussive collisions. Co-localized significant increases in cerebral metabolic rate of oxygen consumption (CMRO2|0) mid-season were also documented in the HIGH group, with respect to both PRE- and POST values. No physiological changes were observed in the LOW group. Therefore, cerebral metabolic demand may be elevated in players with greater exposure to head impacts. These results provide novel insight into the effects of sub-concussive collisions on brain structure and cerebrovascular physiology and emphasize the importance of multi-modal imaging for a complete characterization of cerebral health.
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Affiliation(s)
- Allen A Champagne
- Centre for Neuroscience Studies, Queen’s
University, Kingston, ON, Canada
| | - Nicole S Coverdale
- Centre for Neuroscience Studies, Queen’s
University, Kingston, ON, Canada
| | - Mike Germuska
- Cardiff University Brain Research
Imaging Center, Cardiff University, Cardiff, UK
| | - Alex A Bhogal
- Department of Radiology, University
Medical Center Utrecht, Utrecht, The Netherlands
| | - Douglas J Cook
- Centre for Neuroscience Studies, Queen’s
University, Kingston, ON, Canada
- Department of Surgery, Queen’s
University, Kingston, ON, Canada
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94
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Iverson GL, Luoto TM, Karhunen PJ, Castellani RJ. Mild Chronic Traumatic Encephalopathy Neuropathology in People With No Known Participation in Contact Sports or History of Repetitive Neurotrauma. J Neuropathol Exp Neurol 2020; 78:615-625. [PMID: 31169877 DOI: 10.1093/jnen/nlz045] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
It has been asserted that chronic traumatic encephalopathy (CTE) pathology is only present in former athletes and others who have been exposed to repetitive concussions, subconcussive blows, or both. We hypothesized that CTE pathology would be present in men who had no known history of repetitive neurotrauma. Comprehensive medical record reviews and health surveys completed by a family member were available for the 8 men in this case series, none of whom had known exposure to repetitive neurotrauma but 2 of whom had a history of traumatic brain injury (TBI). Postmortem tissue was immunostained for hyperphosphorylated tau (p-tau) to assess for CTE pathology, Braak stage, and aging-related p-tau. The neuropathologist was blind to age, personal history, and clinical history. Six of the 8 cases (75%) showed p-tau in neurons, astrocytes, and cell processes around small blood vessels in an irregular pattern at the depths of the cortical sulci. The changes were focal and limited in terms of overall extent, and some of the cases had a clearer pattern of pathology and some could be considered equivocal. Two of the 8 cases had a history of TBI and one of them showed CTE pathology. Five of the 6 cases with no known history of neurotrauma appeared to meet consensus criteria for CTE. This study adds to the emerging literature indicating that CTE pathology is present in people not known to have experienced multiple concussions or subconcussive blows to the head.
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Affiliation(s)
- Grant L Iverson
- Department of Physical Medicine and Rehabilitation, Harvard Medical School.,Spaulding Rehabilitation Hospital, Spaulding Research Institute.,MassGeneral Hospital for Children™ Sports Concussion Program.,Home Base, A Red Sox Foundation and Massachusetts General Hospital Program, Boston, Massachusetts
| | - Teemu M Luoto
- Department of Neurosurgery, Tampere University Hospital and University of Tampere, Tampere, Finland
| | - Pekka J Karhunen
- Department of Forensic Medicine, Faculty of Medicine and Life Sciences, University of Tampere.,Fimlab Laboratories and Finnish Cardiovascular Research Center Tampere, Tampere, Finland
| | - Rudolph J Castellani
- Department of Pathology, Anatomy and Laboratory Medicine.,Department of Neuroscience, Rockefeller Neuroscience Institute.,West Virginia University School of Medicine, Morgantown, West Virginia
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95
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Chen W, Post A, Karton C, Gilchrist MD, Robidoux M, Hoshizaki TB. A comparison of frequency and magnitude of head impacts between Pee Wee And Bantam youth ice hockey. Sports Biomech 2020; 22:728-751. [PMID: 32538288 DOI: 10.1080/14763141.2020.1754450] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The purpose of this research was to compare the frequency and magnitude of head impact events between Pee Wee and Bantam ice hockey players. Videos of Pee Wee and Bantam boys' ice hockey were analysed to determine the frequency and type of head impact events. The head impact events were then reconstructed in the laboratory using physical and finite element models to determine the magnitude of strain in the brain tissues. The results showed that Pee Wee boys experienced more head impacts from elbows and boards, while Bantam players had more head impacts to the glass. Pee Wee and Bantam players experienced similar frequency and magnitudes of very low, low, and medium and above (med+) levels of strain to the brain. This research suggests to ice hockey leagues and coaches that to reduce the incidence of these levels of brain trauma, consideration must be given to either reducing the level of contact along the boards or the removal of body checking. In addition, companies who innovate in ice hockey should develop protective devices and equipment strategies that aim to reduce the risk of head injury from shoulder and glass impacts for Bantam players.
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Affiliation(s)
- Wesley Chen
- Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Andrew Post
- Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
- School of Mechanical and Materials Engineering, University College Dublin, Dublin, Ireland
| | - Clara Karton
- Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Michael D. Gilchrist
- School of Mechanical and Materials Engineering, University College Dublin, Dublin, Ireland
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96
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Zhou Y, Chen Q, Wang Y, Wu H, Xu W, Pan Y, Gao S, Dong X, Zhang JH, Shao A. Persistent Neurovascular Unit Dysfunction: Pathophysiological Substrate and Trigger for Late-Onset Neurodegeneration After Traumatic Brain Injury. Front Neurosci 2020; 14:581. [PMID: 32581697 PMCID: PMC7296179 DOI: 10.3389/fnins.2020.00581] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 05/12/2020] [Indexed: 12/14/2022] Open
Abstract
Traumatic brain injury (TBI) represents one of the major causes of death worldwide and leads to persisting neurological deficits in many of the survivors. One of the most significant long-term sequelae deriving from TBI is neurodegenerative disease, which is a group of incurable diseases that impose a heavy socio-economic burden. However, mechanisms underlying the increased susceptibility of TBI to neurodegenerative disease remain elusive. The neurovascular unit (NVU) is a functional unit composed of neurons, neuroglia, vascular cells, and the basal lamina matrix. The key role of NVU dysfunction in many central nervous system diseases has been revealed. Studies have proved the presence of prolonged structural and functional abnormalities of the NVU after TBI. Moreover, growing evidence suggests impaired NVU function is also implicated in neurodegenerative diseases. Therefore, we propose the Neurovascular Unit Dysfunction (NVUD) Hypothesis, in which the persistent NVU dysfunction is thought to underlie the development of post-TBI neurodegeneration. We deduce NVUD Hypothesis through relational inference and supporting evidence, and suggest continued NVU abnormalities following TBI serve as the pathophysiological substrate and trigger yielding chronic neuroinflammation, proteinopathies and oxidative stress, consequently leading to the progression of neurodegenerative diseases. The NVUD Hypothesis may provide potential treatment and prevention strategies for TBI and late-onset neurodegenerative diseases.
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Affiliation(s)
- Yunxiang Zhou
- Department of Surgical Oncology, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Qiang Chen
- Department of Surgical Oncology, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Yali Wang
- Department of Surgical Oncology, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Haijian Wu
- Department of Neurosurgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Weilin Xu
- Department of Neurosurgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Yuanbo Pan
- Department of Neurosurgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Shiqi Gao
- Department of Neurosurgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Xiao Dong
- Department of Neurosurgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - John H. Zhang
- Department of Physiology and Pharmacology, Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, CA, United States
- Department of Anesthesiology, Neurosurgery and Neurology, School of Medicine, Loma Linda University, Loma Linda, CA, United States
| | - Anwen Shao
- Department of Neurosurgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
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97
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Champagne AA, Distefano V, Boulanger MM, Magee B, Coverdale NS, Gallucci D, Guskiewicz K, Cook DJ. Data-informed Intervention Improves Football Technique and Reduces Head Impacts. Med Sci Sports Exerc 2020; 51:2366-2374. [PMID: 31269008 PMCID: PMC7028524 DOI: 10.1249/mss.0000000000002046] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
INTRODUCTION Although sport participation is a key contributor to the physical and mental health of children and youth, exposure to subconcussive head impacts in football has raised concerns about safety for athletes. PURPOSE To demonstrate the efficacy of incorporating targeted football drills into a team's practice routine with the goal of improving players' technique and reduce exposure to subconcussive head impacts. METHODS Seventy high school football players (age, 16.4 ± 1.1 yr) were tested PRE season using a sport-specific functional assessment. Results from the testing were used to inform the design of a prepractice intervention aimed at improving tackling and blocking techniques while reducing exposure to head impacts. The assessment included drills which evaluated the players' ability to safely tackle, and block while simulating game-like situations. Testing was repeated at MID season (internal control) without an intervention, and again at POST season (experimental), after introduction of the prepractice intervention between these timepoints, administered twice weekly. All testing sessions were recorded, and subsequently reviewed by trained graders based on selected criteria defined by football coaches. A subset of 19 participants wore in-helmet accelerometers to assess the effectiveness of the intervention in decreasing head impacts during practice. RESULTS Significant improvements in blocking and tackling techniques were observed after the introduction of the intervention (P < 0.0001). Participating athletes also showed better techniques when evaluated in new game-like situations, postseason, providing evidence for proper acquisition and generalizability of these safer habits. Finally, frequency of head impacts (>15g) per practice was significantly reduced by ~30% after 1 month of training. CONCLUSION Our results suggest that data-informed methods can be used to improve coaching practices and promote safer play, which can have a positive public health impact moving forward.
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Affiliation(s)
- Allen A Champagne
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, CANADA
| | - Vincent Distefano
- School of Applied Child Psychology, McGill Connections Lab, Montréal, QC, CANADA
| | | | - Blaire Magee
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, CANADA
| | - Nicole S Coverdale
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, CANADA
| | | | - Kevin Guskiewicz
- Matthew Gfeller Sport-Related TBI Research Center, University of North Carolina-Chapel Hill, Chapel Hill, NC
| | - Douglas J Cook
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, CANADA.,Department of Surgery, Queen's University, Kingston, ON, CANADA
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98
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Alterations of transcriptome signatures in head trauma-related neurodegenerative disorders. Sci Rep 2020; 10:8811. [PMID: 32483284 PMCID: PMC7264177 DOI: 10.1038/s41598-020-65916-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 05/12/2020] [Indexed: 12/14/2022] Open
Abstract
Chronic traumatic encephalopathy (CTE) is a neurodegenerative disease that is associated with repetitive traumatic brain injury (TBI). CTE is known to share similar neuropathological features with Alzheimer’s disease (AD), but little is known about the molecular properties in CTE. To better understand the neuropathological mechanism of TBI-related disorders, we conducted transcriptome sequencing analysis of CTE including AD and CTE with AD (CTE/AD) post-mortem human brain samples. Through weighted gene co-expression network analysis (WGCNA) and principal component analysis (PCA), we characterized common and unique transcriptome signatures among CTE, CTE/AD, and AD. Interestingly, synapse signaling-associated gene signatures (such as synaptotagmins) were commonly down-regulated in CTE, CTE/AD, and AD. Quantitative real-time PCR (qPCR) and Western blot analyses confirmed that the levels of synaptotagmin 1 (SYT1) were markedly decreased in CTE and AD compared to normal. In addition, calcium/calmodulin-dependent protein kinase II (CaMKII), protein kinase A (PKA), protein kinase C (PKC), and AMPA receptor genes that play a pivotal role in memory function, were down-regulated in head trauma-related disorders. On the other hand, up-regulation of cell adhesion molecules (CAMs) associated genes was only found in CTE. Our results indicate that dysregulation of synaptic transmission- and memory function-related genes are closely linked to the pathology of head injury-related disorder and AD. Alteration of CAMs-related genes may be specific pathological markers for the CTE pathology.
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99
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Iverson GL, Gardner AJ, Shultz SR, Solomon GS, McCrory P, Zafonte R, Perry G, Hazrati LN, Keene CD, Castellani RJ. Chronic traumatic encephalopathy neuropathology might not be inexorably progressive or unique to repetitive neurotrauma. Brain 2020; 142:3672-3693. [PMID: 31670780 PMCID: PMC6906593 DOI: 10.1093/brain/awz286] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 07/01/2019] [Accepted: 07/15/2019] [Indexed: 12/11/2022] Open
Abstract
In the 20th century, chronic traumatic encephalopathy (CTE) was conceptualized as a neurological disorder affecting some active and retired boxers who had tremendous exposure to neurotrauma. In recent years, the two research groups in the USA who have led the field have asserted definitively that CTE is a delayed-onset and progressive neurodegenerative disease, with symptoms appearing in midlife or decades after exposure. Between 2005 and 2012 autopsy cases of former boxers and American football players described neuropathology attributed to CTE that was broad and diverse. This pathology, resulting from multiple causes, was aggregated and referred to, in toto, as the pathology ‘characteristic’ of CTE. Preliminary consensus criteria for defining the neuropathology of CTE were forged in 2015 and published in 2016. Most of the macroscopic and microscopic neuropathological findings described as characteristic of CTE, in studies published before 2016, were not included in the new criteria for defining the pathology. In the past few years, there has been steadily emerging evidence that the neuropathology described as unique to CTE may not be unique. CTE pathology has been described in individuals with no known participation in collision or contact sports and no known exposure to repetitive neurotrauma. This pathology has been reported in individuals with substance abuse, temporal lobe epilepsy, amyotrophic lateral sclerosis, multiple system atrophy, and other neurodegenerative diseases. Moreover, throughout history, some clinical cases have been described as not being progressive, and there is now evidence that CTE neuropathology might not be progressive in some individuals. Considering the current state of knowledge, including the absence of a series of validated sensitive and specific biomarkers, CTE pathology might not be inexorably progressive or specific to those who have experienced repetitive neurotrauma.
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Affiliation(s)
- Grant L Iverson
- Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, Massachusetts, USA.,Spaulding Rehabilitation Hospital and Spaulding Research Institute, Boston, Massachusetts, USA.,MassGeneral Hospital for Children™ Sports Concussion Program, Boston, Massachusetts, USA.,Home Base, A Red Sox Foundation and Massachusetts General Hospital Program, Boston, Massachusetts, USA
| | - Andrew J Gardner
- Hunter New England Local Health District, Sports Concussion Program, University of Newcastle, Callaghan, NSW, Australia.,Centre for Stroke and Brain Injury, School of Medicine and Public Health, University of Newcastle, Callaghan, NSW, Australia
| | - Sandy R Shultz
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia
| | - Gary S Solomon
- Department of Neurological Surgery, Orthopaedic Surgery and Rehabilitation, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.,Department of Psychiatry and Behavioral Sciences, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.,Vanderbilt Sports Concussion Center, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Paul McCrory
- The Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre - Austin Campus, Heidelberg, Victoria Australia
| | - Ross Zafonte
- Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, Massachusetts, USA.,Spaulding Rehabilitation Hospital and Spaulding Research Institute, Boston, Massachusetts, USA.,Home Base, A Red Sox Foundation and Massachusetts General Hospital Program, Boston, Massachusetts, USA
| | - George Perry
- College of Sciences, University of Texas, San Antonio; San Antonio, Texas, USA
| | - Lili-Naz Hazrati
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - C Dirk Keene
- Department of Pathology, Division of Neuropathology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Rudolph J Castellani
- Department of Pathology, Anatomy and Laboratory Medicine, West Virginia University School of Medicine, Morgantown, USA.,Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University School of Medicine, Morgantown, USA
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100
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Laksari K, Fanton M, Wu LC, Nguyen TH, Kurt M, Giordano C, Kelly E, O'Keeffe E, Wallace E, Doherty C, Campbell M, Tiernan S, Grant G, Ruan J, Barbat S, Camarillo DB. Multi-Directional Dynamic Model for Traumatic Brain Injury Detection. J Neurotrauma 2020; 37:982-993. [PMID: 31856650 PMCID: PMC7175617 DOI: 10.1089/neu.2018.6340] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Given the worldwide adverse impact of traumatic brain injury (TBI) on the human population, its diagnosis and prediction are of utmost importance. Historically, many studies have focused on associating head kinematics to brain injury risk. Recently, there has been a push toward using computationally expensive finite element (FE) models of the brain to create tissue deformation metrics of brain injury. Here, we develop a new brain injury metric, the brain angle metric (BAM), based on the dynamics of a 3 degree-of-freedom lumped parameter brain model. The brain model is built based on the measured natural frequencies of an FE brain model simulated with live human impact data. We show that it can be used to rapidly estimate peak brain strains experienced during head rotational accelerations that cause mild TBI. In our data set, the simplified model correlates with peak principal FE strain (R2 = 0.82). Further, coronal and axial brain model displacement correlated with fiber-oriented peak strain in the corpus callosum (R2 = 0.77). Our proposed injury metric BAM uses the maximum angle predicted by our brain model and is compared against a number of existing rotational and translational kinematic injury metrics on a data set of head kinematics from 27 clinically diagnosed injuries and 887 non-injuries. We found that BAM performed comparably to peak angular acceleration, translational acceleration, and angular velocity in classifying injury and non-injury events. Metrics that separated time traces into their directional components had improved model deviance compare with those that combined components into a single time trace magnitude. Our brain model can be used in future work to rapidly approximate the peak strain resulting from mild to moderate head impacts and to quickly assess brain injury risk.
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Affiliation(s)
- Kaveh Laksari
- Department of Biomedical Engineering, University of Arizona, Tucson, Arizona
- Department of Bioengineering, Stanford University, Stanford, California
| | - Michael Fanton
- Department of Mechanical Engineering, Stanford University, Stanford, California
| | - Lyndia C. Wu
- Department of Bioengineering, Stanford University, Stanford, California
- Department of Mechanical Engineering, University of British Columbia, Vancouver, British Columbia, Canada
| | - Taylor H. Nguyen
- Department of Bioengineering, Stanford University, Stanford, California
| | - Mehmet Kurt
- Department of Bioengineering, Stanford University, Stanford, California
- Department of Mechanical Engineering, Stevens Institute of Technology, Hoboken, New Jersey
| | - Chiara Giordano
- Department of Bioengineering, Stanford University, Stanford, California
| | - Eoin Kelly
- Department of Neurology, Health Care Centre, Hospital 5, St James's Hospital, Dublin, Ireland
| | - Eoin O'Keeffe
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin, Ireland
| | - Eugene Wallace
- Department of Neurology, Health Care Centre, Hospital 5, St James's Hospital, Dublin, Ireland
| | - Colin Doherty
- Department of Neurology, Health Care Centre, Hospital 5, St James's Hospital, Dublin, Ireland
| | - Matthew Campbell
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin, Ireland
| | - Stephen Tiernan
- Department of Mechanical Engineering, Technological University Dublin, Tallaght, Dublin, Ireland
| | - Gerald Grant
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, California
| | | | | | - David B. Camarillo
- Department of Biomedical Engineering, University of Arizona, Tucson, Arizona
- Department of Bioengineering, Stanford University, Stanford, California
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