Trends in the Prevalence of Concussion Reported by US Adolescents, 2016-2020

Concussion Awareness Training Tool for Youth: Impact on Concussion Knowledge, Beliefs, and Reporting Intentions

BACKGROUND

Concussion education is recommended to increase concussion knowledge, beliefs, and reporting intentions. The Concussion Awareness Training Tool for Youth (CATT-Youth) is a 40-minute e-Learning module developed for high school-aged youth.

AIM

The aim of the study was to evaluate changes in concussion knowledge, beliefs, and reporting intentions in high school youth from Calgary, Canada, following completion of the CATT-Youth.

METHODS

This study used a modified stepped-wedge trial design. High school classes were randomly assigned to an intervention (Ix) or delayed intervention (DIx) group. Ix group participants completed a pre-CATT survey immediately followed by the CATT-Youth, then a post-CATT survey 2 to 6 weeks later. DIx group participants completed two pre-CATT surveys 2 to 6 weeks apart, with the CATT-Youth completed immediately following the second pre-CATT, then a post-CATT survey 2 to 6 weeks later. The pre-/post-CATT survey encompassed 11 subtests evaluating concussion knowledge, beliefs, and reporting intentions. Independent mixed linear regression models were conducted to examine changes in scores for each subtest.

RESULTS

Participants included 454 high school students: five Ix schools (16 classes, n = 323) and two DIx schools (six classes, n = 131). The CATT-Youth significantly increased general concussion knowledge, Ix δ = 0.546/8 (95% confidence interval [CI] = [0.243, 0.849]), DIx δ = 0.728/8 (95% CI = [0.389, 1.106]), and beliefs about capabilities, Ix δ = 2.462/28 (95% CI = [1.086, 3.838]), DIx δ = 3.219/28 (95% CI = [1.594, 4.844]) for both groups. For some subtests, improvements were noted in the DIx group only.

CONCLUSION

The CATT-Youth module improved concussion knowledge and beliefs about capabilities for students in both groups. Future studies should explore the utility of the CATT-Youth in changing knowledge, beliefs, and reporting intentions in high school students.

Long-term cognitive and affective consequences of mild traumatic brain injury: comparison with older adults

OBJECTIVE

Memory and affective processing were compared in young adults with a remote mild traumatic brain injury (mTBI), to healthy younger and older adults. We evaluated memory performance when encoding was done under multi-tasking (divided attention) conditions, likely to exacerbate cognitive and psychological symptoms in mTBI.

METHODS

Participants studied pairs of unrelated words under either full or divided attention conditions. Memory for single words (item memory) and for pairs of words (associative memory) was then assessed in sequential independent recognition tests, under full attention.

RESULTS

Associative memory was poorer than item memory, and worse when encoding was done under divided than full attention. The decline in recognition accuracy from full to divided attention conditions on the associative memory test was significantly greater in mTBI compared to young adults and was similar in magnitude to that observed in older adults under full attention. Self-reported mental and total fatigue increased significantly as performance on the memory tests, following the divided attention condition, decreased, but only in the mTBI group.

CONCLUSIONS

Results show lingering memory deficits, and suggest that cognitive tasks may be experienced as psychologically more demanding in those with a mTBI, even months or years after injury.

Factors Influencing Time to Return to Learn Among NCAA Student-Athletes Enrolled in the Concussion Assessment, Research, and Education (CARE) Study

PURPOSE

The aim was to describe the demographic and post-injury factors that influence time to return to learn (RTL) among student-athletes enrolled in the Concussion Assessment, Research and Education (CARE) Consortium.

METHODS

A total of 47,860 student-athletes enrolled in the National Collegiate Athletic Association-Department of Defense (NCAA-DoD) CARE Consortium study from 2014 to 2020, with 1485 sport-related concussions (SRCs) analyzed in the present dataset. Demographic and post-injury characteristics were calculated using descriptive statistics, followed by Kaplan-Meier estimates to examine median time to return to normal academic performance (i.e., RTL) by sex (male, female), baseline psychiatric conditions (depression, anxiety) and/or learning disorder, NCAA division (I, II, III), SRC history (0, 1, 2, 3+), NCAA sport category (contact, limited contact, non-contact sport), and median difference in baseline/post-injury symptom severity scores (< 21, ≥ 21). Further, a multivariable zero-inflated negative binomial (ZINB) regression model was used to examine their association with RTL.

RESULTS

Overall, time to RTL (mean = 4.96 ± 8.24 days, median = 3.0 [interquartile range = 0.0, 6.0] days) was found to be influenced by several factors resulting in earlier trajectories. Notably, nearly 25% of the sample demonstrated immediate RTL (i.e., 0 days). Among student-athletes who did not immediately RTL, males demonstrated a decreased rate in RTL (rate = 0.79; 95% CI 0.66-0.96) compared to females. Further, student-athletes with a ≥ 21 change in symptom severity score (post-injury baseline) demonstrated a higher rate of RTL (rate = 1.47; 95% CI 1.21-1.79) compared to student-athletes with a symptom severity change score < 21. Lastly, male student-athletes demonstrated two times higher odds (odds ratio = 1.95; 95% CI 1.02-3.73) of immediate RTL compared to female student-athletes. No other covariates were associated with time to RTL.

CONCLUSION

Collectively, the present findings suggest a rapid return to the classroom following concussion. Specifically, males demonstrated higher odds of time to RTL, whereas those with greater differences in symptom severity resulted in a higher rate of time to RTL among those who did not immediately RTL. Ultimately, these findings support prior work emphasizing an individualized approach to SRC management.

Working Memory Recovery in Adolescents with Concussion: Longitudinal fMRI Study

Background: Understanding the behavioral and neural underpinnings of the post-concussion recovery of working memory function is critically important for improving clinical outcomes and adequately planning return-to-activity decisions. Previous studies provided inconsistent results due to small sample sizes and the use of a mixed population of participants who were at different post-injury time points. We aimed to examine working memory recovery during the first 6 months post-concussion in adolescents. Methods: We used functional magnetic resonance imaging (fMRI) to scan 45 concussed adolescents [CONCs] at baseline (<10 days post-concussion) and at 6 months post-concussion. Healthy control adolescents [HCs; n = 32] without a history of concussion were scanned once. During the scans, participants performed one-back and two-back working memory tasks with letters as the stimuli and angry, happy, neutral, and sad faces as distractors. Results: All affected adolescents were asymptomatic and cleared to return to activity 6 months after concussion. Working memory recovery was associated with faster and more accurate responses at 6 months vs. baseline (p-values < 0.05). It was also characterized by significant difficulty-related activation increases in the left inferior frontal gyrus (LIFG) and the left orbitofrontal cortex (LOFC) at 6 months vs. baseline. Although the activation differences between one-back and two-back were comparable between HCs and CONCs at 6 months, HCs had more pronounced activation in the LIFG than concussed adolescents. Conclusions: Post-concussion recovery is associated with significant performance improvements in speed and accuracy, as well as the normalization of brain responses in the LIFG and LOFC during the n-back task. The observed patterns of LOFC activation might reflect compensatory strategies to distribute neural processing and reduce neural fatigue post-concussion.

Geographic characteristics of sport- and non-sport-related concussions presenting to emergency departments in the United States

BACKGROUND

Concussion is a type of traumatic brain injury (TBI) that can be sustained through sport-related and non-sport-related (e.g., motor vehicle accidents, falls, assaults) mechanisms of injury (MOI). Variations in concussion incidence and MOI may be present throughout the four geographic regions (Midwest, Northeast, South, West) of the United States. However, there is limited evidence exploring concussion cause and diagnosis patterns based on geographic region and MOI. These factors have implications for better understanding the burden of concussion and necessary efforts that can translate to the mitigation of safety concerns.

PURPOSE

The purpose of this study was to identify patterns of sport-related concussion (SRC) and non-sport-related concussion (NSRC) across the four geographic regions of the United States.

METHODS

A descriptive epidemiology study of patient visits to the emergency department (ED) for concussion between 2010 and 2018, using publicly available data from the National Hospital Ambulatory Medical Care Survey (NHAMCS) was conducted. The exposure of interest was geographic region while the main outcome measures were concussion diagnosis and MOI. Descriptive statistics were calculated using population-weighted frequencies and percentages. The association between geographic region and MOI (SRC vs. NSRC) was analyzed using logistic regression models. Odds ratios (OR) presented with 95% confidence intervals (CI) were included. Univariate analyses were conducted followed by multivariable analyses adjusting for sex, age, race/ethnicity, and primary source of payment. Statistical significance was set a priori at p < 0.05 for all analyses.

RESULTS

From 2010 to 2018, 1,161 visits resulted in a concussion diagnosis, representing an estimated 7,111,856 visits nationwide. A greater proportion of concussion diagnoses occurred within EDs in the South (38.2%) followed by the West (25.8%), Midwest (21.4%), and Northeast (14.6%). Compared to the West region, patients visiting the ED in the Midwest (OR = 0.75, 95% CI = 0.57-0.98) and Northeast (OR = 0.71, 95% CI = 0.51-0.98) had a lower odds of being diagnosed with a concussion. More patients sustained a NSRC MOI (94.3%) compared to SRC MOI (5.7%). For both mechanisms, the South region had the highest population-weighted frequency of SRC (n = 219,994) and NSRC diagnoses (n = 2,495,753). Univariate and multivariable logistic regression analyses did not reveal statistically significant associations for geographic region and MOI (p > 0.05).

CONCLUSION

Our findings showed that the Midwest and Northeast regions had a lower odds of concussion diagnoses in EDs. Overall, the vast majority of concussions were not sport-related, which has public health implications. These findings improve our understanding of how concussion injuries are being sustained geographically nationwide and help to explain care-seeking patterns for concussion in the ED setting.

Assessment of post-concussion emotional symptom load using PCSS and PROMIS instruments in pediatric patients

OBJECTIVES

The purpose of this study is to evaluate the utility of the Patient-Reported Outcomes Measurement Information System (PROMIS) anxiety and depressive symptom domains in conjunction with the Post-Concussion Symptom Scale (PCSS)for identifying pediatric patients with emotional symptoms following a concussion, and to identify predictors of higher emotional symptom loads.

METHODS

We recruited English-speaking patients aged 8-17 years presenting to a tertiary-care concussion clinic from 2014 to 2018 (n = 458). Demographics and clinical data including PCSS, injury date, previous history of anxiety/depression, and Vestibular/Ocular-Motor Screen (VOMS) were collected from patients' electronic medical records. Participants completed surveys in the PROMISTM Pediatric Item Bank v1.1-Anxiety and Depressive Symptoms domains at their initial clinic visit. Multivariable linear regression identified predictors of higher emotional symptom loads.

RESULTS

Overall, 425 (92.8%) reported ≥1 emotional symptom on either PROMIS or PCSS. Predictors of higher emotional symptom loads were abnormal VOMS, female sex, history of anxiety or depression, and longer time since injury.

CONCLUSION

Our results suggest that adding PROMIS anxiety and depressive symptom surveys to pediatric concussion evaluations may identify more children with emotional symptoms, allowing clinicians to better direct post-concussion treatment and incorporate psychological support for patients if necessary. Future studies should examine whether earlier identification of emotional symptoms with these tools facilitates recovery and improves short- and/or long-term psychological outcomes in pediatric concussion.

Response Rate Patterns in Adolescents With Concussion Using Mobile Health and Remote Patient Monitoring: Observational Study

Background

A concussion is a common adolescent injury that can result in a constellation of symptoms, negatively affecting academic performance, neurobiological development, and quality of life. Mobile health (mHealth) technologies, such as apps for patients to report symptoms or wearables to measure physiological metrics like heart rate, have been shown to be promising in health maintenance. However, there is limited evidence about mHealth engagement in adolescents with a concussion during their recovery course.

Objective

This study aims to determine the response rate and response rate patterns in concussed adolescents reporting their daily symptoms through mHealth technology. It will also examine the effect of time-, demographic-, and injury-related characteristics on response rate patterns.

Methods

Participants aged between 11-18 years (median days since injury at enrollment: 11 days) were recruited from the concussion program of a tertiary care academic medical center and a suburban school's athletic teams. They were asked to report their daily symptoms using a mobile app. Participants were prompted to complete the Post-Concussion Symptom Inventory (PCSI) 3 times (ie, morning, afternoon, and evening) per day for 4 weeks following enrollment. The primary outcome was the response rate pattern over time (by day since initial app use and the day since injury). Time-, demographic-, and injury-related differences in reporting behaviors were compared using Mann Whitney U tests.

Results

A total of 56 participants were enrolled (mean age 15.3, SD 1.9 years; n=32, 57% female). The median response rate across all days of app use in the evening was 37.0% (IQR 27.2%-46.4%), which was significantly higher than the morning (21.2%, IQR 15.6%-30.5%) or afternoon (26.4%, IQR 21.1%-31.5%; P<.001). The median daily response was significantly different by sex (female: 53.8%, IQR 46.2%-64.2% vs male: 42.0%, IQR 28.6%-51.1%; P=.003), days since injury to app use (participants starting to use the app >7 days since injury: 54.1%, IQR 47.4%-62.2% vs starting to use the app ≤7 days since injury: 38.0%, IQR 26.0%-53.3%; P=.002), and concussion history (participants with a history of at least one prior concussion: 57.4%, IQR 44.5%-70.5% vs participants without concussion history: 42.3%, IQR 36.8%-53.5%; P=.03). There were no significant differences by age. Differences by injury mechanism (sports- and recreation-related injury: 39.6%, IQR 36.1%-50.4% vs non-sports- or recreation-related injury: 30.6%, IQR 20.0%-42.9%; P=.04) and initial symptom burden (PCSI scores greater than the median score of 47: 40.9%, IQR 35.2%-53.8% vs PCSI scores less than or equal to the median score: 31.9%, IQR 24.6%-40.6%; P=.04) were evident in the evening response rates; however, daily rates were not statistically different.

Conclusions

Evening may be the optimal time to prompt for daily concussion symptom assessment among concussed adolescents compared with morning or afternoon. Multiple demographic- and injury-related characteristics were associated with higher daily response rates, including for female participants, those with more than 1 week from injury to beginning mHealth monitoring, and those with a history of at least one previous concussion. Future studies may consider incentive strategies or adaptive digital concussion assessments to increase response rates in populations with low engagement.

Experienced Clinical Decision-Making in Physical Therapist Management of Concussion: A Qualitative Study

OBJECTIVE

The recent publication of the Physical Therapy Evaluation and Treatment After Concussion Clinical Practice Guideline is intended to assist clinicians in their decision-making specific to evaluation and intervention. Clinical practice guidelines are supported by best available evidence, though it is unknown what other factors drive clinical decision-making in the realm of concussion management. The purpose of this study was to explore factors related to the process of clinical decision-making of experienced physical therapists who treat individuals with concussion.

METHODS

This grounded theory approach used semi-structured interviews of physical therapists who have practiced concussion management ≥3 years and have treated ≥15 individuals for postconcussion symptoms in the last year. Following the inductive approach, deductive qualitative methodology was used to explore alignment with recent guidelines. Member checking was used to ensure trustworthiness.

RESULTS

Ten therapists' experience in treating concussion ranged from 5 to 20 years. Four overarching themes were identified that contribute to clinical decision-making: expert practice behaviors through use of reflection in action, clinical reasoning, collaboration, and evidenced informed practice; therapeutic alliance building using individualized education, reassurance, and relationship building; adaptability in prioritizing, assessing, and responding to patients' needs; and listening and observing. Clinician decision-making statements showed alignment with clinical practice guideline recommendations.

CONCLUSION

Experienced therapists demonstrate a consistent approach that parallels the current clinical practice guideline while building off clinical experience to tailor individualized care focusing on patient centeredness. These factors may assist more novice clinicians to develop and improve their management strategies for optimal outcomes.

IMPACT

Identified themes may broaden frameworks and guidelines for the management of individuals postconcussion specific to the field of physical therapy.

Symptom resolution following a repeat concussion within the same athlete

INTRODUCTION

Repeat sport-related concussion (SRC) is anecdotally associated with prolonged recovery. Few studies have examined repeat concussion within the same athlete. We sought to explore differences in symptom burden and recovery outcomes in an individual athlete's initial and repeat SRC.

METHODS

A retrospective within-subject cohort study of athletes aged 12-23 years diagnosed with two separate SRCs from 11/2017-10/2020 was conducted. Primary outcomes were initial symptom severity and time-to-symptom-resolution. Secondary outcomes included return-to-learn (RTL) and return-to-play (RTP) duration.

RESULTS

Of 868 athletes seen, 47 athletes presented with repeat concussions. Median time between concussions was 244 days (IQR 136-395). Comparing initial to repeat concussion, no differences were observed in time-to-clinic (4.3 ± 7.3vs.3.7 ± 4.6 days, p = 0.56) or initial PCSS (26.2 ± 25.3 vs. 30.5 ± 24.1, p = 0.32). While a difference was observed in time-to-symptom resolution between initial/repeat concussion (21.2 ± 16.3 vs. 41.7 ± 86.0 days, p = 0.30), this did not reach statistical significance. No significant differences were observed in time-to-RTL (17.8 ± 60.6 vs. 6.0 ± 8.3 days, p = 0.26) and RTP (33.2 ± 44.1 vs. 29.4 ± 39.1 days, p = 0.75). Repeat concussion was not associated with symptom resolution on univariate (HR 1.64, 95% CI 0.96-2.78, p = 0.07) and multivariable (HR 0.85, 95% CI 0.49-1.46, p = 0.55) Cox regression.

CONCLUSION

No significant differences in symptom duration and RTP/RTL were seen between initial/repeat concussion.

Specialist healthcare services for concussion/mild traumatic brain injury in England: a consensus statement using modified Delphi methodology

OBJECTIVE

To establish a consensus on the structure and process of healthcare services for patients with concussion in England to facilitate better healthcare quality and patient outcome.

DESIGN

This consensus study followed the modified Delphi methodology with five phases: participant identification, item development, two rounds of voting and a meeting to finalise the consensus statements. The predefined threshold for agreement was set at ≥70%.

SETTING

Specialist outpatient services.

PARTICIPANTS

Members of the UK Head Injury Network were invited to participate. The network consists of clinical specialists in head injury practising in emergency medicine, neurology, neuropsychology, neurosurgery, paediatric medicine, rehabilitation medicine and sports and exercise medicine in England.

PRIMARY OUTCOME MEASURE

A consensus statement on the structure and process of specialist outpatient care for patients with concussion in England.

RESULTS

55 items were voted on in the first round. 29 items were removed following the first voting round and 3 items were removed following the second voting round. Items were modified where appropriate. A final 18 statements reached consensus covering 3 main topics in specialist healthcare services for concussion; care pathway to structured follow-up, prognosis and measures of recovery, and provision of outpatient clinics.

CONCLUSIONS

This work presents statements on how the healthcare services for patients with concussion in England could be redesigned to meet their health needs. Future work will seek to implement these into the clinical pathway.

Racial differences in concussion diagnosis and mechanism of injury among adults presenting to emergency departments across the United States

OBJECTIVES

The purpose of this study was to examine the association between race and concussion diagnosis as well as the association between race and mechanism of injury (MOI) for concussion diagnoses in adult patients (>19 years old) visiting the emergency department (ED).

METHODS

A retrospective analysis of patient visits to the ED for concussion between 2010 and 2018, using the National Hospital Ambulatory Medical Care Survey, was conducted. Outcome measures included concussion diagnosis and MOI. Multivariable and multinomial logistic regression analyses were conducted to assess associations between race and outcome variables. The results were weighted to reflect population estimates with a significance set at p < 0.05.

RESULTS

Overall, 714 patient visits for concussions were identified, representing an estimated 4.3 million visits nationwide. Black adults had lower odds of receiving a concussion diagnosis [p < 0.05, Odds Ratio (OR), 0.54; 95% Confidence Interval (CI), 0.38-0.76] compared to White adults in the ED. There were no significant differences in MOI for a concussion diagnosis by race.

CONCLUSION

Racial differences were found in the ED for concussion diagnosis. Disparities in concussion diagnosis for Black or other minoritized racial groups could have significant repercussions that may prolong recovery or lead to long-term morbidity.

Driving characteristics of young adults prior to and following concussion

OBJECTIVES

This study sought to examine whether young adults who sustain concussions have different driving histories and pre-injury driving styles than uninjured peers. In addition, we assessed whether modifications were made to driving behavior in the acute period following concussion.

METHODS

Self-reported driving and demographic information was collected from 102 16- to 25-year-old drivers. Half of the sample had recently sustained concussions and the other half comprised a matched comparison group.

RESULTS

The groups reported similar pre-injury driving behaviors and styles. However, the recently injured group had more driving citations, higher rates of psychiatric disorders, and greater likelihood of having sustained a prior concussion. Self-reported driving habits postconcussion suggested that most drivers did not modify their driving behavior following concussion, though they were less likely to drive at night or with others in the car.

CONCLUSION

Results highlight the need for postconcussion driving guidelines and support for returning to driving safely.

Affective Disturbance and Neurocognitive Variability in College Athletes

OBJECTIVE

Research on the neurocognitive effects of comorbid mood/anxiety disturbance in college athletes is limited. Previous research found that athletes with comorbid depression/anxiety performed worse on measures of attention/processing speed (A/PS) at baseline compared to healthy controls. However, this work solely examined mean performance. The current study expands upon this work by examining intraindividual variability (IIV) in relation to affective disturbance.

METHOD

835 (M = 624, F = 211) collegiate athletes completed baseline neuropsychological testing. Athletes were separated into four groups (Healthy Mood [n = 582], Depression Alone [n = 137], Anxiety Alone [n = 54], and Co-Occurring Depression/Anxiety [n = 62]) based on self-reported anxiety and depression. IIV was examined globally and within composites of A/PS and memory via intraindividual standard deviation, with higher scores indicating greater variability.

RESULTS

Linear regression results revealed that the Co-Occurring Depression/Anxiety group exhibited greater variability within the memory composite compared to the Healthy Mood group, as well as the Depression Alone and Anxiety Alone groups. The Depression Alone and Anxiety Alone groups did not differ from the Healthy Mood group on memory IIV. None of the groups differed on A/PS or global IIV.

CONCLUSIONS

Athletes with co-occurring depression/anxiety demonstrated greater variability in performance on memory tasks. Greater dispersion is predictive of greater cognitive decline following concussion; therefore, it is important that neuropsychological performance is interpreted beyond measures of central tendency. These findings also highlight the importance of having baseline data available for athletes with affective disturbance, as these factors may influence performance, place athlete at risk for poorer outcomes, and skew future post-concussion comparisons.

Concussion Exposure and Suicidal Ideation, Planning, and Attempts Among US High School Students

CONTEXT

Interest is growing in the association between repetitive concussions and mental health. However, studies on the relationship between concussion frequency and adverse mental health outcomes among female and male youth are lacking.

OBJECTIVES

To examine the association between self-reported concussion frequency and nonfatal suicidal behaviors among youth and to explore the possible interaction of biological sex.

DESIGN

Retrospective cross-sectional survey.

SETTING

National Youth Risk Behavior Surveillance System.

PATIENTS OR OTHER PARTICIPANTS

United States secondary school students (N = 28 442).

MAIN OUTCOME MEASURE(S)

Exposure variables were the frequency of self-reported sport- or recreation-related concussion in the previous 12 months (0, 1, ≥2). Outcome variables were feelings of self-reported sadness or hopelessness and suicidal ideation, planning, and attempts. Covariates were age, sex, race and ethnicity, bullying victimization, sexual orientation, and physical activity.

RESULTS

Students who reported ≥2 concussions were at significantly greater odds of reporting suicidal attempts (adjusted odds ratio = 2.03; 95% CI = 1.43, 2.88) when compared with students reporting a single concussive event during the past 12 months. However, sex interactions revealed that this finding may have been driven by males; the strength of associations did not increase from single to multiple concussions among females.

CONCLUSIONS

Our findings suggest that adolescents who reported concussion were at increased odds of reporting poor mental health and suicidal behaviors. Moreover, an increased number of concussive events may be associated with significantly greater odds of reporting suicidal attempts, particularly among males. Irrespective of sex, health care professionals should closely monitor mental health behaviors in adolescents with repetitive concussions, especially those that occur in close temporal proximity.

The association between sleep and physical activity with persisting postconcussion symptoms among adolescent athletes

BACKGROUND

Both sleep duration and physical activity following concussion may influence subsequent recovery. Objective measurement of sleep and physical activity behavior via wearable technology may provide insights into their association with concussion recovery.

OBJECTIVE

To determine whether sleep behavior (eg, duration, timing) and/or physical activity (steps/day, or exercise frequency, duration, intensity) in the first month after adolescent sports-related concussion are associated with developing persisting postconcussion symptoms (PPCS).

DESIGN

Case-control.

SETTING

Outpatient sports medicine clinic.

PARTICIPANTS

The study prospectively enrolled adolescent athletes who sustained a concussion (N = 49, age = 14.8 ± 1.8 years; 51% female) who were evaluated within 14 days of concussion (mean = 6.7 ± 2.7 days) and followed uvia sleep/physical activity monitoring for the subsequent 2 weeks.

MAIN OUTCOME MEASURES

Participants wore a monitor to track sleep (sleep time, wake time, and time spent awake in bed at night) and physical activity (average steps/day, exercise frequency, exercise duration) behavior for 2 weeks after initial assessment. Participants were followed until symptom resolution, and the main outcome of interest was development of PPCS (symptom duration >28 days). A multivariable logistic regression model was used to examine associations between physical activity and sleep behavior with PPCS.

RESULTS

Of the 49 participants, 47% (n = 23, mean symptom resolution = 57 ± 23 days post injury) developed PPCS and 53% (n = 26, mean symptom resolution = 15 ± 7 days post injury) did not. Univariable analysis showed that the PPCS group took fewer steps/day (7526 ± 2975 vs. 9803 ± 3786 steps/day; p = .02), exercised less frequently (2.5 ± 2.2 vs. 4.4 ± 2.1 days/week; p = .005), and spent more time in bed awake (1.2 ± 0.3 vs. 0.8 ± 0.3 h/night; p = .03) than the no PPCS group. Multivariable results indicated the odds of developing PPCS significantly increased with fewer exercise session/week (adjusted odds ratio = 1.96, 95% confidence interval = 1.09, 3.51, p = .024).

CONCLUSIONS

More exercise sessions that were longer than 15 minutes during concussion recovery was associated with a lower risk of developing PPCS, whereas sleep and other physical activity measures were not. Further studies regarding exercise duration and intensity are needed. Clinicians may consider advising patients to optimize sleep and physical activity during concussion recovery.

Adolescents With More Oculomotor and Vestibular Signs of Sport-Related Concussion Benefit from Aerobic Exercise: An Exploratory Analysis

Abstract Early targeted heart rate (HR) aerobic exercise has been shown to reduce the duration of recovery from sport-related concussion (SRC) as well as the incidence of persistent post-concussive symptoms (PPCS). It is not known, however, if more severe oculomotor and vestibular presentations of SRC benefit from a prescription of aerobic exercise. The current study is an exploratory analysis of two published randomized controlled trials that compared aerobic exercise within 10 days of injury with a placebo-like stretching intervention. Combining the two studies yielded a larger sample size to stratify severity of concussion based on the number of abnormal physical examination signs present at the initial office evaluation, which were confirmed with self-reported symptoms and recovery outcomes. The most discriminant cut-off was between those who had ≤3 oculomotor and vestibular signs and those who had >3 signs. Aerobic exercise (hazard ratio = 0.621 [0.412, 0.936], p = 0.023) reduced recovery times even when controlling for site (hazard ratio = 0.461 [0.303, 0.701], p < 0.001), severity (hazard ratio = 0.528 [0.325, 0.858], p = 0.010) and the interaction term of intervention and severity (hazard ratio = 0.972 [0.495, 1.909], p = 0.935). Adolescents who presented with >3 signs and were assigned to the placebo-like stretching group had a PPCS incidence of 38%, which was the highest of all subgroups (aerobic exercise and ≤3 findings: 8%; stretching and ≤3 findings: 11%; aerobic exercise and >3 findings: 21%). This exploratory study provides pilot evidence that prescribed sub-symptom threshold aerobic exercise treatment early after SRC may be effective for adolescents with more oculomotor and vestibular physical examination signs and should be validated in future adequately powered trials.

Gender Differences in Adolescents' Affective Symptoms and Behavioral Disorders After Mild Traumatic Brain Injury

OBJECTIVE

Mild traumatic brain injuries (mTBI) are considered self-limiting and full recovery is expected. Recent studies identify deficits persisting years after mTBI. Large-scale prospective data permit testing the hypothesis that mTBI increases incidence of affective and behavioral symptoms after new, past , or new and past mTBI.

SETTING

The study involved secondary analyses of survey responses from the Adolescent Brain Cognitive Development (ABCD) Study.

PARTICIPANTS

Adolescents in the ABCD Study ( n = 11 869; Wave 1, aged 9-10 years; Wave 2, aged 11-12 years) whose parents reported a new ( n = 157), past ( n = 1318), or new and past ( n = 50) mTBI on the Ohio State University Traumatic Brain Injury Identification Method short form were compared with controls who had no history of mTBI ( n = 9,667).

DESIGN

Multivariable binary logistic regression models examined associations between a new, past, or new and past mTBI and current affective (aggression, depression, anxiety) and behavioral (somatic, thought, social, attention, attention deficit hyperactivity disorder, conduct) disorders while controlling for demographic factors and baseline symptoms.

MAIN MEASURES

The primary measure was parental reports of psychiatric and behavioral symptoms on the Child Behavior Checklist.

RESULTS

Girls exhibited no significant effects after a new mTBI, although a past mTBI increased anxiety (adjusted odds ratios [aOR] = 1.83, 95% confidence interval [CI: 1.15-2.90]) and attention (1.89 [1.09-3.28]) problems. Girls with new and past mTBIs reported elevated anxiety (17.90 [4.67-68.7]), aggression (7.37 [1.49-36.3]), social (9.07 [2.47-33.30]), thought (7.58 [2.24-25.60]), and conduct (6.39 [1.25-32.50]) disorders. In boys, new mTBI increased aggression (aOR = 3.83, 95% CI [1.42-10.30]), whereas past mTBI heightened anxiety (1.91 [1.42-2.95]), but new and past mTBIs had no significant effects.

CONCLUSION

Adolescents are at greater risk of affective and behavioral symptoms after an mTBI. These effects differ as a function of gender and time of injury. Extended screening for mTBI history and monitoring of affective and behavioral disorders after mTBI in adolescents are warranted.

Characterizing the Network Structure of Post-Concussion Symptoms

OBJECTIVE

Assessment of post-concussion symptoms is implemented at secondary, post-secondary, and professional levels of athletics. Network theory suggests that disorders can be viewed as a set of interacting symptoms that amplify, reinforce, and maintain one another. Examining the network structure of post-concussion symptoms may provide new insights into symptom comorbidity and may inform targeted treatment. We used network analysis to examine the topology of post-concussion symptoms using the Post-Concussion Symptom Scale (PCSS) in high school athletes with recent suspected sport-related concussion.

METHOD

Using a cross-sectional design, the network was estimated from Post Concussion Symptom Scale scores from 3,292 high school athletes, where nodes represented symptoms and edges represented the association between symptoms. Node centrality was calculated to determine the relative importance of each symptom in the network.

RESULTS

The network consisted of edges within and across symptom domains. "Difficulty concentrating" and "dizziness" were the most central symptoms in the network. Although not highly central in the network, headaches were the highest rated symptom.

CONCLUSIONS

The interconnectedness among symptoms supports the notion that post-concussion symptoms are interrelated and mutually reinforcing. Given their central role in the network, "difficulty concentrating" and "dizziness" are expected to affect the activation and persistence of other post-concussion symptoms. Interventions targeting difficulties with concentration and dizziness may help alleviate other symptoms. Our findings could inform the development of targeted treatment with the aim of reducing overall symptom burden. Future research should examine the trajectory of post-concussion symptom networks to advance the clinical understanding of post-concussive recovery.

Relationship between anxiety and concussion symptoms among adolescents enrolled in a randomized controlled trial of aerobic exercise

BACKGROUND

Affective symptoms, specifically, anxiety, are often overlooked after sport-related concussion (SRC), and may contribute to prolonged recovery.

OBJECTIVE

To examine the impact of anxiety during clinical recovery among adolescents (13-18y) enrolled in a randomized trial of aerobic exercise for SRC.

METHODS

Patients at three sites were randomized into aerobic exercise or stretching arms, and enrolled in the 4-week intervention. The relationship between PROMIS Anxiety score at initial visit and time to symptom resolution was evaluated with survival analysis. The relationship between weekly PROMIS Anxiety score and Post-concussion Symptom Inventory (PCSI) score was evaluated with Linear Mixed Models. Analyses adjusted for study arm and baseline covariates.

RESULTS

Among 54 adolescents (median age = 15.8y, initial visit PCSI score = 32, pre-injury PROMIS Anxiety score = 2), median time to symptom resolution was 10 days (25th-75th percentiles: 6-24) in the Low-PROMIS Anxiety group and 12 days (25th-75th percentiles: 5-21) in the High-PROMIS Anxiety group (p = 0.62). Each additional unit of PROMIS Anxiety score corresponded to a 1.52-unit higher PCSI total score (p <  0.01). Neither effect varied by aerobic exercise/stretching group.

CONCLUSION

Higher initial PROMIS Anxiety score was not significantly associated with delayed symptom resolution. However, over time, PROMIS Anxiety score was significantly associated with elevated PCSI score, regardless of exercise/stretching group.

Magnetic resonance spectroscopy of traumatic brain injury and subconcussive hits: A systematic review and meta-analysis

Magnetic resonance spectroscopy (MRS) is a non-invasive technique used to study metabolites in the brain. MRS findings in traumatic brain injury (TBI) and subconcussive hit literature have been mixed. The most common observation is a decrease in N-acetyl-aspartate (NAA), traditionally considered a marker of neuronal integrity. Other metabolites, however, such as creatine (Cr), choline (Cho), glutamate+glutamine (Glx) and myo-inositol (mI) have shown inconsistent changes in these populations. The objective of this systematic review and meta-analysis was to synthesize MRS literature in head injury and explore factors (brain region, injury severity, time since injury, demographic, technical imaging factors, etc.) that may contribute to differential findings. One hundred and thirty-eight studies met inclusion criteria for the systematic review and of those, 62 NAA, 24 Cr, 49 Cho, 18 Glx and 21 mI studies met inclusion criteria for meta-analysis. A random effects model was used for meta-analyses with brain region as a subgroup for each of the five metabolites studied. Meta-regression was used to examine the influence of potential moderators including injury severity, time since injury, age, sex, tissue composition and methodological factors. In this analysis of 1428 unique head-injured subjects and 1132 controls, the corpus callosum was identified as a brain region highly susceptible to metabolite alteration. NAA was consistently decreased in TBI of all severity, but not in subconcussive hits. Cho and mI were found to be increased in moderate-to-severe TBI but not mild TBI. Glx and Cr were largely unaffected, however did show alterations in certain conditions.

Perceptions of Symptom Duration are Associated With Emotional Distress and Functioning in Adolescents With Protracted Concussion Recovery

 

Adolescents with persisting post-concussive symptoms often report high levels of emotional distress, which can impact their daily functioning. The associations between modifiable factors, such as perceptions of recovery, and emotional distress have not been investigated in this age group.

Objective

To evaluate perceptions about recovery duration (e.g., “my symptoms will last a long time”, “my symptoms will be permanent rather than temporary”) and its associations with emotional distress and functioning in children and adolescents with a slower post-concussive recovery.

Methods

Participants (N = 49, 69% girls, 11–17 years old, M = 15.8 years old, SD = 1.8) were recruited from a concussion clinic on average 7.7 months after injury (SD = 2.5). Measures included the Illness Perception Questionnaire Revised (perceived duration of symptoms only) to evaluate recovery expectations, the Health and Behavior Inventory (self and parent reports) to evaluate current post-concussive symptoms (cognitive and somatic symptoms), the emotional distress subscale of the Strengths and Difficulties Questionnaire (SDQ—self-report), and the emotional functioning subscale of the Pediatric Quality of Life Questionnaire (PedsQL—self-report).

Results

Regression analyses (linear models with all covariates entered at once) suggested that greater expectations for symptom persistence were significantly associated with higher emotional distress on both SDQ and PedsQL subscales, after controlling for post-concussive symptom severity and other confounds. Emotional distress/functioning was not associated with perceptions of symptom duration reported by parents, severity of post-concussive symptoms (self- and parent reports), age, number of concussions, time since injury, or a history of mental health concern or diagnosis (parent-reported).

Conclusions

This study suggests that pessimistic attitudes for recovery duration may be more strongly associated with emotional distress than current post-concussive symptom severity or a history of mental health concern or diagnosis.