A prospective biopsychosocial study of the persistent post-concussion symptoms following mild traumatic brain injury

Pilot feasibility randomised controlled trial of cognitive-behavioural therapy for functional cognitive disorder after concussion

Background

Functional cognitive disorder (FCD) may be common after a concussion, and no evidence-based treatment options are available. The current study evaluated the feasibility of a novel cognitive-behavioural therapy (CBT) protocol tailored to FCD after concussion.

Methods

Participants were randomised to CBT (n=11) or the current standard of care, cognitive rehabilitation (n=13). Both interventions consisted of eleven 50 min manualised videoconference sessions. CBT involved cognitive reappraisal and exposure-based strategies. Cognitive rehabilitation involved traditional memory compensation strategy training. Prespecified feasibility criteria were set for recruitment, perceived credibility, patient adherence, therapist protocol compliance and retention. The primary efficacy outcome was the Multifactorial Memory Questionnaire-Satisfaction (MMQ-S). The first five CBT completers completed a semistructured interview about their experience with the intervention.

Results

Most feasibility benchmarks were met, as 86% of invited patients consented, 96% of participants rated their intervention as credible, participants attended 96% of sessions, therapists covered all essential content in 94% of sessions and 100% of participants completed the post-treatment evaluation. Both groups improved on the MMQ-S. Post-treatment MMQ-S scores were similar between groups (Cohen's d=-0.05 (95% CI [-0.86, 0.75])). Two themes resulted from the qualitative data analysis, which highlighted aspects of the CBT interventions that participants valued.

Implications

This pilot trial supports the feasibility of CBT tailored to FCD after concussion and suggests that patients with FCD may benefit from either CBT or standard cognitive rehabilitation. A larger trial is needed to evaluate the efficacy of these interventions for FCD after concussion and potentially FCD in other clinical contexts.

Trial registration number

NCT05581810.

Rasch analysis of the depression anxiety stress scales-21 (DASS-21) in a mild traumatic brain injury sample

OBJECTIVE

In this study, we evaluated the psychometric properties of the Depression Anxiety Stress Scales 21 items (DASS-21) in a mild traumatic brain injury (mTBI) sample.

METHOD

Treatment-seeking adults (n = 347) were recruited from outpatient rehabilitation services in New Zealand. Dimensionality, reliability, person separation index, and differential item functioning (DIF) of the DASS-21 were examined using Rasch analysis.

RESULTS

Initial analysis of the complete 21-item DASS showed poor overall fit due to problems with individual items. Fit to the Rasch model was excellent when treated as three composite scores. The stress subscale demonstrated adequate model fit, dimensionality and good reliability. For anxiety, fit was not good, reliability was unsatisfactory and DIF was evident on one item. When this item was removed, fit to the model was still inadequate as was reliability. DIF was also evident for depression, but when this item was removed, fit to the model was adequate.

CONCLUSION

The DASS-21 is a psychometrically sound measure of distress and stress for adults seeking treatment following mTBI. Ordinal to interval score conversion tables are provided to increase the precision of measurement. When assessing depression in a mTBI population, a 6-item depression subscale is recommended. Caution is advised in using the DASS-21 anxiety subscale alone.

Predicting Recovery After Concussion in Pediatric Patients: A Meta-Analysis

CONTEXT

Prognostic prediction models (PPMs) can help clinicians predict outcomes.

OBJECTIVE

To critically examine peer-reviewed PPMs predicting delayed recovery among pediatric patients with concussion.

DATA SOURCES

Ovid Medline, Embase, Ovid PsycInfo, Web of Science Core Collection, Cumulative Index to Nursing and Allied Health Literature, Cochrane Library, Google Scholar.

STUDY SELECTION

The study had to report a PPM for pediatric patients to be used within 28 days of injury to estimate risk of delayed recovery at 28 days to 1 year postinjury. Studies had to have at least 30 participants.

DATA EXTRACTION

The Critical Appraisal and Data Extraction for Systematic Reviews of Prediction Modeling Studies checklist was completed.

RESULTS

Six studies of 13 PPMs were included. These studies primarily reflected male patients in late childhood or early adolescence presenting to an emergency department meeting the Concussion in Sport Group concussion criteria. No study authors used the same outcome definition nor evaluated the clinical utility of a model. All studies demonstrated high risk of bias. Quality of evidence was best for the Predicting and Preventing Postconcussive Problems in Pediatrics (5P) clinical risk score.

LIMITATIONS

No formal PPM Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) process exists.

CONCLUSIONS

The 5P clinical risk score may be considered for clinical use. Rigorous external validations, particularly in other settings, are needed. The remaining PPMs require external validation. Lack of consensus regarding delayed recovery criteria limits these PPMs.

Identification of At-Risk Patients That Need More Intensive Treatment Following mTBI: Post-Hoc Insights From the UPFRONT-Study

OBJECTIVE

To investigate which factors within an at-risk group make patients less likely to benefit from preventive treatment following mild traumatic brain injury (mTBI).

SETTING

Inclusion in 3 level I trauma centers in the Netherlands. Data collection through surveys as outpatients.

PARTICIPANTS

mTBI patients (18-66 years), reporting 3 or more complaints 2 weeks postinjury (at-risk status). Eighty-four patients included and randomized (39 patients cognitive behavioral therapy, 45 patients telephonic counseling). Eighty patients filled out the questionnaires 12 months postinjury. Post hoc analysis investigating 80 patients as 1 at-risk group receiving psychological treatment.

DESIGN

Post hoc study of a randomized controlled trial (RCT). Binomial logistic regression performed determining which variables 2 weeks postinjury contributed strongly to unsuccessful return to work/study (RTW) and unfavorable outcome at 12 months.

MAIN MEASURES

RTW and functional outcome as measured with the Glasgow Outcome Scale-Extended (GOSE) at 12 months postinjury.

RESULTS

Out of 80 patients, 43 (53.8%) showed a favorable functional outcome at 12 months, and 56 (70%) patients had a full RTW. Patients with unfavorable outcome had a higher age and higher reports of anxiety, depression at 2 weeks and 12 months postinjury. Patients with an unsuccessful RTW had a higher age and higher reports of depression, and posttraumatic stress disorder at 2 weeks and 12 months postinjury. A logistic regression model for functional outcome (GOSE) was statistically significant (χ² 7 = 40.30, P < .0001). Of 6 predictor variables, 3 were significant: anxiety, depression, and treatment condition. For RTW, logistic regression was also statistically significant (χ² 7 = 19.15, P = .008), with only 1 out of 6 predictor variables (ie, age) being significant.

CONCLUSION

Main findings comprise differences in demographic and psychological measures between patients with favorable and unfavorable outcomes and patients with RTW versus no RTW. Prediction models of outcome and RTW showed several psychological measures at 2 weeks greatly determining patients' likelihood benefitting from the preventive treatment. Results suggest that from the beginning there are some patients for whom a short preventive treatment is not sufficient. Selection and treatment of at-risk patients might be better based on psychological symptoms instead of posttraumatic complaints.

Evaluation of a biopsychosocial education resource for mild traumatic brain injury: a mixed method exploratory study

Introduction

Education is strongly advocated as a key component of treatment for mild traumatic brain injury (mTBI) in clinical guidelines. However, there is mixed evidence on the benefit of education. This study aimed to evaluate a new education resource for mTBI. CLARITY is a freely available animated video based on a biopsychosocial conceptualization of mTBI, explaining the complex psychological, environmental and biological mechanisms behind symptoms and recovery.

Methods

24 adults with a history of mTBI participated in this mixed method study to examine prior experience of mTBI education and to evaluate CLARITY. Following viewing of the education video participants' were invited to engage in a semi-structured interview and to share their perceptions of it via an online anonymous questionnaire.

Results

Thematic analysis of semi-structured interviews revealed one overarching theme: education is the foundation of recovery. Participants emphasised the critical role of coherent education in facilitating understanding, engagement in rehabilitation, and positive expectations during recovery. However, the first subtheme was that existing foundations are weak. Participants' previous education was often limited in scope, inconsistent, and delivered in inaccessible ways. The second subtheme was that new foundations are stronger. Participants responded positively to CLARITY, highlighting its explanatory biopsychosocial approach, focus on mental health factors and accessible delivery methods as key strengths. Questionnaire responses revealed favourable endorsement of CLARITY's utility, comprehensibility and accessibility.

Discussion

Recommendations for minor refinements to CLARITY were provided and made, as well as for its use in health care services.

Evidence for Altered White Matter Organization After Mild Traumatic Brain Injury: A Scoping Review on the Use of Diffusion Magnetic Resonance Imaging and Blood-Based Biomarkers to Investigate Acute Pathology and Relationship to Persistent Post-Concussion Symptoms

Mild traumatic brain injury (mTBI) is the most common form of traumatic brain injury. Post-concussive symptoms typically resolve after a few weeks although up to 20% of people experience these symptoms for >3 months, termed persistent post-concussive symptoms (PPCS). Subtle white matter (WM) microstructural damage is thought to underlie neurological and cognitive deficits experienced post-mTBI. Evidence suggests that diffusion magnetic resonance imaging (dMRI) and blood-based biomarkers could be used as surrogate markers of WM organization. We conducted a scoping review according to PRISMA-ScR guidelines, aiming to collate evidence for the use of dMRI and/or blood-based biomarkers of WM organization, in mTBI and PPCS, and document relationships between WM biomarkers and symptoms. We focused specifically on biomarkers of axonal or myelin integrity post-mTBI. Biomarkers excluded from this review therefore included the following: astroglial, perivascular, endothelial, and inflammatory markers. A literature search performed across four databases, EMBASE, Scopus, Google Scholar, and ProQuest, identified 100 records: 68 analyzed dMRI, 28 assessed blood-based biomarkers, and 4 used both. Blood biomarker studies commonly assessed axonal cytoskeleton proteins (i.e., tau); dMRI studies assessed measures of WM organization (i.e., fractional anisotropy). Significant biomarker alterations were frequently associated with heightened symptom burden and prolonged recovery time post-injury. These data suggest that dMRI and blood-based biomarkers may be useful proxies of WM organization, although few studies assessed these complementary measures in parallel, and the relationship between modalities remains unclear. Further studies are warranted to assess the benefit of a combined biomarker approach in evaluating alterations to WM organization after mTBI.

Rehabilitation of Persistent Symptoms After Concussion

Persistent symptoms following a mild traumatic brain injury are challenging to treat and pose a significant threat to community reintegration. Early recognition and intervention play a pivotal role in preventing the development of persistent symptoms by providing education that emphasizes clear recovery expectations and the high likelihood of full symptom resolution. We recommend early development of a personalized treatment plan, offering guidance on gradual return to activity and specific symptom-targeted treatments that may incorporate both pharmacologic and nonpharmacologic interventions.

Diffusion tensor analysis of white matter tracts is prognostic of persisting post-concussion symptoms in collegiate athletes

BACKGROUND AND OBJECTIVES

After a concussion diagnosis, the most important issue for patients and loved ones is how long it will take them to recover. The main objective of this study is to develop a prognostic model of concussion recovery. This model would benefit many patients worldwide, allowing for early treatment intervention.

METHODS

The Concussion Assessment, Research and Education (CARE) consortium study enrolled collegiate athletes from 30 sites (NCAA athletic departments and US Department of Defense service academies), 4 of which participated in the Advanced Research Core, which included diffusion-weighted MRI (dMRI) data collection. We analyzed the dMRI data of 51 injuries of concussed athletes scanned within 48 h of injury. All athletes were cleared to return-to-play by the local medical staff following a standardized, graduated protocol. The primary outcome measure is days to clearance of unrestricted return-to-play. Injuries were divided into early (return-to-play < 28 days) and late (return-to-play >= 28 days) recovery based on the return-to-play clinical records. The late recovery group meets the standard definition of Persisting Post-Concussion Symptoms (PPCS). Data were processed using automated, state-of-the-art, rigorous methods for reproducible data processing using brainlife.io. All processed data derivatives are made available at https://brainlife.io/project/63b2ecb0daffe2c2407ee3c5/dataset. The microstructural properties of 47 major white matter tracts, 5 callosal, 15 subcortical, and 148 cortical structures were mapped. Fractional Anisotropy (FA) and Mean Diffusivity (MD) were estimated for each tract and structure. Correlation analysis and Receiver Operator Characteristic (ROC) analysis were then performed to assess the association between the microstructural properties and return-to-play. Finally, a Logistic Regression binary classifier (LR-BC) was used to classify the injuries between the two recovery groups.

RESULTS

The mean FA across all white matter volume was negatively correlated with return-to-play (r = -0.38, p = 0.00001). No significant association between mean MD and return-to-play was found, neither for FA nor MD for any other structure. The mean FA of 47 white matter tracts was negatively correlated with return-to-play (rμ = -0.27; rσ = 0.08; rmin = -0.1; rmax = -0.43). Across all tracts, a large mean ROC Area Under the Curve (AUCFA) of 0.71 ± 0.09 SD was found. The top classification performance of the LR-BC was AUC = 0.90 obtained using the 16 statistically significant white matter tracts.

DISCUSSION

Utilizing a free, open-source, and automated cloud-based neuroimaging pipeline and app (https://brainlife.io/docs/tutorial/using-clairvoy/), a prognostic model has been developed, which predicts athletes at risk for slow recovery (PPCS) with an AUC=0.90, balanced accuracy = 0.89, sensitivity = 1.0, and specificity = 0.79. The small number of participants in this study (51 injuries) is a significant limitation and supports the need for future large concussion dMRI studies and focused on recovery.

Relationships between vestibular issues, noise sensitivity, anxiety and prolonged recovery from mild traumatic brain injury among adults: a scoping review

BACKGROUND

We investigated the extent of literature and findings on relationships between vestibular issues, noise sensitivity (NS), and anxiety. We were interested in how relationships among these factors impacted adults' recovery three months or more after mild traumatic brain injury (mTBI).

METHODS

We conducted a scoping review to evaluate the extent of evidence linking relationships between vestibular issues, NS and anxiety with recovery after mTBI. Data relating to study characteristics and key findings were extracted and used to inform a critical narrative synthesis of findings.

RESULTS

After screening and full-text review, we included two studies. Both studies considered the combination of vestibular issues, NS and anxiety and mTBI recovery. Vestibular issues, NS and anxiety were all significantly associated with one another and their presence was the strongest indicator that symptoms would extend beyond three-months after mTBI.

CONCLUSION

Few studies have focused on the relationships that vestibular issues, NS and anxiety have with one another and recovery after mTBI. Given the apparent strong relationships between these factors and prolonged recovery, we highlight this as an area warranting further investigation.

"Alone in the dark": A qualitative study of treatment experiences among young adults with a recent concussion and anxiety

PURPOSE

Young adults with anxiety are vulnerable to developing persistent symptoms following concussions. In order to develop psychosocial interventions to prevent persistent post-concussion symptoms, we need to understand patients' 1) experiences with treatments offered by health care providers; 2) experiences with attempted concussion management strategies; and 3) needs after their injury.

METHODS

We conducted in-depth interviews with 17 young adults with recent (≤ 10 weeks) concussions who have at least mild anxiety (Generalized Anxiety Disorder Assessment-7 ≥ 5). We used a hybrid deductive-inductive approach to thematic analysis.

RESULTS

Findings provide insight into recommended treatments (e.g., active/avoidant strategies, accommodations, referrals), attempted strategies (e.g., lifestyle changes, pacing, relationships, acceptance-based coping skills), and patient needs (e.g., education, accommodations, referrals for cognitive and emotional skills). Participants frequently expressed that treatment recommendations were confusing and difficult to implement. They initiated non-prescribed strategies that helped promote recovery and expressed a desire for more interdisciplinary treatment and education on concussions.

CONCLUSION

Patients' perceptions of health care provider recommendations after concussions did not fully meet patients' perceived needs. Young adults with concussions and anxiety would benefit from more education, guidance, and psychosocial and rehabilitation services. Addressing these gaps may help align treatments with patients' needs and therefore help optimize their recovery.

"I hope it'll get better… in the end, it didn't really get better": a qualitative study of access to specialized rehabilitation services as experienced by adults with persistent MTBI symptoms

PURPOSE

Persistent symptoms experienced by adults following mild traumatic brain injury (mTBI) can significantly impact their daily activities. It is often difficult for them to access specialized rehabilitation services. The aim of this study is to explore this population's experience surrounding access to specialized rehabilitation services, including waiting time.

MATERIALS AND METHODS

This study used a qualitative phenomenological approach and was conducted using semi-structured interviews. Twelve adults with mTBI who had received specialized interdisciplinary rehabilitation services were recruited. The interviews focused on participants' recollection of their patient journey after injury, their perception of waiting, barriers and facilitators to access, and the impacts of these experiences on their condition.

RESULTS

Participants reported experiencing symptoms such as anxiety, depression, worry, sadness, and discouragement before accessing specialized services. They all agreed that they did not receive clear information about their recovery process or the health services available to them, which exacerbated their mental health symptoms.

CONCLUSION

The findings show that participants experienced uncertainty because they lacked information regarding recovery and access to health services after their injury. Education about symptoms and recovery, as well as emotional support for people with mTBI should be made available during the waiting period.

Co-existence of depression and post-concussion syndrome one month after mild traumatic brain injury

BACKGROUND

Previous studies suggest an association between Post-concussion syndrome (PCS) and depression, both highly prevalent after mTBI.

OBJECTIVE

To assess the prevalence and risk-factors of depression among patients with PCS 1 month after mTBI.

METHODS

We prospectively screened 372 mTBI patients admitted in two academic Emergency Departments between 2017 and 2019. One month after mTBI, we administered the Rivermead Post-concussion symptoms Questionnaire (RPQ) and the Patient Health Questionnaire (PHQ-9) questionnaires over the telephone. PCS and depression were defined by RPQ ≥ 12 and PHQ-9 ≥ 10. Multivariate multinomial regression identified baseline factors associated with PCS and depression.

RESULTS

Two hundred and eight completed RPQ and PHQ-9. Forty-seven patients (22.5%) met criteria for PCS, among which 22 (46.8%) met criteria for depression (PCS+D+). Patients with PCS but without depression were less likely to present with an associated injury (Coefficient = -1.6, p = 0.047) and to report initial sadness (Coefficient = -2.5, p = 0.03). Initial sadness (Coefficient = -1.3, p = 0.047), associated injury (Coefficient = -1.9, p = 0.008), as well as initial nausea (Coefficient = -1.8, p = 0.002), and male sex (Coefficient = 1.8, p = 0.002), were associated with the absence of depression and PCS in comparison with PCS+D+ patients.

CONCLUSION

Among patients with PCS 1 month after mTBI, those with depression are more likely to present with initial sadness and with an associated injury.

Impact of PTSD treatment on postconcussive symptoms in veterans: A comparison of sertraline, prolonged exposure, and their combination

Many Veterans who served in Iraq and Afghanistan struggle with posttraumatic stress disorder (PTSD) and the effects of traumatic brain injuries (TBI). Some people with a history of TBI report a constellation of somatic, cognitive, and emotional complaints that are often referred to as postconcussive symptoms (PCS). Research suggests these symptoms may not be specific to TBI. This study examined the impact of PTSD treatment on PCS in combat Veterans seeking treatment for PTSD. As part of a larger randomized control trial, 198 Operation Iraqi Freedom, Operation Enduring Freedom, Operation New Dawn (OIF/OEF/OND) Veterans with PTSD received Prolonged Exposure Therapy, sertraline, or the combination. Potential deployment related TBI, PCS, PTSD and depression symptoms were assessed throughout treatment. Linear mixed models were used to predict PCS change over time across the full sample and treatment arms, and the association of change in PTSD and depression symptoms on PCS was also examined. Patterns of change for the full sample and the subsample of those who reported a head injury were examined. Results showed that PCS decreased with treatment. There were no significant differences across treatments. No significant differences were found in the pattern of symptom change based on TBI screening status. Shifts in PCS were predicted by change PTSD and depression. Results suggest that PCS reduced with PTSD treatment in this population and are related to shift in depression and PTSD severity, further supporting that reported PCS symptoms may be better understood as non-specific symptoms.

Longitudinal Associations Between Persistent Post-Concussion Symptoms and Blood Biomarkers of Inflammation and CNS-Injury After Mild Traumatic Brain Injury

The aim of our study was to investigate the biological underpinnings of persistent post-concussion symptoms (PPCS) at 3 months following mild traumatic brain injury (mTBI). Patients (n = 192, age 16-60 years) with mTBI, defined as Glasgow Coma Scale (GCS) score between 13 and 15, loss of consciousness (LOC) <30 min, and post-traumatic amnesia (PTA) <24 h were included. Blood samples were collected at admission (within 72 h), 2 weeks, and 3 months. Concentrations of blood biomarkers associated with central nervous system (CNS) damage (glial fibrillary acidic protein [GFAP], neurofilament light [NFL], and tau) and inflammation (interferon gamma [IFNγ], interleukin [IL]-8, eotaxin, macrophage inflammatory protein-1-beta [MIP]-1β, monocyte chemoattractant protein [MCP]-1, interferon-gamma-inducible protein [IP]-10, IL-17A, IL-9, tumor necrosis factor [TNF], basic fibroblast growth factor [FGF]-basic platelet-derived growth factor [PDGF], and IL-1 receptor antagonist [IL-1ra]) were obtained. Demographic and injury-related factors investigated were age, sex, GCS score, LOC, PTA duration, traumatic intracranial finding on magnetic resonance imaging (MRI; within 72 h), and extracranial injuries. Delta values, that is, time-point differences in biomarker concentrations between 2 weeks minus admission and 3 months minus admission, were also calculated. PPCS was assessed with the British Columbia Post-Concussion Symptom Inventory (BC-PSI). In single variable analyses, longer PTA duration and a higher proportion of intracranial findings on MRI were found in the PPCS group, but no single biomarker differentiated those with PPCS from those without. In multi-variable models, female sex, longer PTA duration, MRI findings, and lower GCS scores were associated with increased risk of PPCS. Inflammation markers, but not GFAP, NFL, or tau, were associated with PPCS. At admission, higher concentrations of IL-8 and IL-9 and lower concentrations of TNF, IL-17a, and MCP-1 were associated with greater likelihood of PPCS; at 2 weeks, higher IL-8 and lower IFNγ were associated with PPCS; at 3 months, higher PDGF was associated with PPCS. Higher delta values of PDGF, IL-17A, and FGF-basic at 2 weeks compared with admission, MCP-1 at 3 months compared with admission, and TNF at 2 weeks and 3 months compared with admission were associated with greater likelihood of PPCS. Higher IL-9 delta values at both time-point comparisons were negatively associated with PPCS. Discriminability of individual CNS-injury and inflammation biomarkers for PPCS was around chance level, whereas the optimal combination of biomarkers yielded areas under the curve (AUCs) between 0.62 and 0.73. We demonstrate a role of biological factors on PPCS, including both positive and negative effects of inflammation biomarkers that differed based on sampling time-point after mTBI. PPCS was associated more with acute inflammatory processes, rather than ongoing inflammation or CNS-injury biomarkers. However, the modest discriminative ability of the models suggests other factors are more important in the development of PPCS.

The protective role of resilience in the reporting of post-concussive symptoms within a non-clinical sample

Objective: Despite being common following a brain injury, post-concussive symptoms (PCS) are highly prevalent in healthy and non-concussed individuals. Psychosocial factors likely subserve the maintenance of symptoms, and numerous studies have identified prominent risk factors associated with post-concussive symptom reporting (e.g. history of depression). However, few studies have investigated protective factors in this context. The aim of the current study was to examine the relationship between resilience and PCS, and to identify the factors subserving resilience within this relationship. Method: Healthy and non-concussed participants (n = 283, Mage = 22.70 years) completed questionnaires examining PCS (Rivermead Post-Concussion Symptom Questionnaire) and resilience (Resilience Scale for Adults), together with a screener of background demographic/clinical factors. Results: Resilience negatively predicted PCS above and beyond the effect of demographic and clinical factors previously implicated in the reporting of PCS. Interestingly, heightened "perception of self" was the resilience factor uniquely associated with PCS symptoms. The final model accounted for 33% of the variance in PCS. Overall, female gender, a history of headaches, and diagnoses of ADHD and depression, and reduced "perception of self" were all predictive of greater PCS (ps < .05). Conclusion: Resilience, particularly perception of self, is a positive protective factor in the reporting of PCS. These findings highlight the importance of early identification of less resilient individuals following trauma-such as an mTBI and provide a potential rationale for the incorporation of resilience-based rehabilitation programs into the recovery process, particularly those that promote greater self-efficacy and self-competency.

Optimizing Concussion Care Seeking: Connecting Care-Seeking Behaviors and Neurophysiological States Through Blood Biomarkers

BACKGROUND

Timely and appropriate medical care after concussion presents a difficult public health problem. Concussion identification and treatment rely heavily on self-report, but more than half of concussions go unreported or are reported after a delay. If incomplete self-report increases exposure to harm, blood biomarkers may objectively indicate this neurobiological dysfunction.

PURPOSE/HYPOTHESIS

The purpose of this study was to compare postconcussion biomarker levels between individuals with different previous concussion diagnosis statuses and care-seeking statuses. It was hypothesized that individuals with undiagnosed concussions and poorer care seeking would show altered biomarker profiles.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Blood samples were collected from 287 military academy cadets and collegiate athletes diagnosed with concussion in the Advanced Research Core of the Concussion Assessment, Research and Education Consortium. The authors extracted each participant's self-reported previous concussion diagnosis status (no history, all diagnosed, ≥1 undiagnosed) and whether they had delayed or immediate symptom onset, symptom reporting, and removal from activity after the incident concussion. The authors compared the following blood biomarkers associated with neural injury between previous concussion diagnosis status groups and care-seeking groups: glial fibrillary acidic protein, ubiquitin c-terminal hydrolase-L1 (UCH-L1), neurofilament light chain (NF-L), and tau protein, captured at baseline, 24 to 48 hours, asymptomatic, and 7 days after unrestricted return to activity using tests of parallel profiles.

RESULTS

The undiagnosed previous concussion group (n = 21) had higher levels of NF-L at 24- to 48-hour and asymptomatic time points relative to all diagnosed (n = 72) or no previous concussion (n = 194) groups. For those with delayed removal from activity (n = 127), UCH-L1 was lower at 7 days after return to activity than that for athletes immediately removed from activity (n = 131). No other biomarker differences were observed.

CONCLUSION

Individuals with previous undiagnosed concussions or delayed removal from activity showed some different biomarker levels after concussion and after clinical recovery, despite a lack of baseline differences. This may indicate that poorer care seeking can create neurobiological differences in the concussed brain.

Screening for Anxiety and Depression Symptoms Using Concussion Symptom Scales Among Varsity Athletes

OBJECTIVE

This study examined associations between Sport Concussion Assessment Tool-5 (SCAT-5) symptom reporting and gold-standard measures of anxiety and depression, and explored the utility SCAT-5 symptom subscales to identify anxiety and depression symptomology.

DESIGN

Prospective cross-sectional study.

SETTING

York University in Toronto, Canada.

PARTICIPANTS

Preseason data were collected for varsity athletes (N = 296) aged between 17 and 25 years ( M = 20.01 years, SD = 1.69 years; 52% male).

MAIN OUTCOME MEASURES

The SCAT-5 symptom evaluation scale was used to assess baseline symptoms. The Generalized Anxiety Disorder Index-7 (GAD-7) and Patient Health Questionnaire-9 (PHQ-9) were used to assess symptoms of anxiety and depression, respectively.

RESULTS

Endorsement of SCAT-5 symptoms of feeling anxious, sadness, irritability, and feeling more emotional had the strongest correlations with the GAD-7 ( r' s > 0.400; P' s < 0.001). Sadness, trouble falling asleep, concentration problems, feeling slowed down, anxious, irritability, mental fog, fatigue, and memory problems had the highest correlations with the PHQ-9 ( r' s >0 .400; P' s < 0.001). The Emotional subscale from the SCAT-5 predicted mild to severe anxiety on the GAD-7 ( P < 0.001). The Sleep, Cognitive, and Emotional subscales predicted mild to severe depression on the PHQ-9 ( P' s < 0.05).

CONCLUSIONS

These findings provide better delineation of symptoms endorsed on the SCAT-5 symptoms that aid in identification of athletes with symptoms of anxiety or depression who may be at risk for developing a clinical disorder or experiencing persistent symptoms after a concussion.

Traumatic brain injury is common and undertreated in the orthopaedic trauma population

INTRODUCTION

Traumatic brain injuries (TBIs) can be difficult to diagnose and are often marginalized when compared to more obvious physical injuries. Despite this, recognition and early treatment can lead to improved outcomes. Even mild TBIs have the potential to cause significant long-term consequences for patients, which may affect their physical recovery from orthopaedic injuries. The objective of this study was to examine the incidence and treatment of TBI within the orthopaedic trauma population.

METHODS

Inclusion criteria were all patients presenting after an acute trauma with an orthopaedic surgery consult over a continuous 3 month timeframe (n = 187). A retrospective review was completed at an academic tertiary referral trauma center. The primary outcome was the rate of TBI. Secondary outcomes included rate of TBI listed as a discharge diagnosis and rate of follow up plan. Several secondary variables were noted and their associations with TBI evaluated.

RESULTS

27 % of the 187 patients had an acute TBI. 61 % of TBI patients had the diagnosis listed in their discharge summary. 6 % had a follow up plan. The positive TBI group was associated with more high energy injuries (p = 0.032), average limbs involved (p = 0.007), upper extremity injury (p < 0.001), bilateral lower extremity injury (p = 0.004), and Injury Severity Score (p < 0.001). 82 % of patients with an acute TBI had an occupational therapy consult and 39 % had a neurosurgery consult. 24 % of patients with a TBI were admitted to the orthopaedic primary service.

CONCLUSIONS

Patients presenting after an acute trauma with orthopaedic injuries have high rates of TBI, but low rates of diagnosis and treatment. This lack of diagnosis and treatment can negatively impact recovery from orthopaedic injuries. Orthopaedic providers should be aware of the diagnostic criteria and initial treatment steps for TBI to ensure prompt and effective treatment, which has been shown to improve outcomes.

Conservative Management of Acute Sports-Related Concussions: A Narrative Review

This review explores the application of the conservative management model for pain to sports-related concussions (SRCs), framing concussions as a distinct form of pain syndrome with a pathophysiological foundation in central sensitization. Drawing parallels with proven pain management models, we underscore the significance of a proactive approach to concussion management. Recognizing concussions as a pain syndrome allows for the tailoring of interventions in alignment with conservative principles. This review first covers the epidemiology and controversies surrounding prolonged concussion recovery and persistent post-concussion symptoms (PPCS). Next, the pathophysiology of concussions is presented within the central sensitization framework, emphasizing the need for early intervention to mitigate the neuroplastic changes that lead to heightened pain sensitivity. Five components of the central sensitization process specific to concussion injuries are highlighted as targets for conservative interventions in the acute period: peripheral sensitization, cerebral metabolic dysfunction, neuroinflammation, glymphatic system dysfunction, and pain catastrophizing. These proactive interventions are emphasized as pivotal in accelerating concussion recovery and reducing the risk of prolonged symptoms and PPCS, in line with the philosophy of conservative management.

Diet's Impact on Post-Traumatic Brain Injury Depression: Exploring Neurodegeneration, Chronic Blood-Brain Barrier Destruction, and Glutamate Neurotoxicity Mechanisms

Traumatic brain injury (TBI) has a profound impact on cognitive and mental functioning, leading to lifelong impairment and significantly diminishing the quality of life for affected individuals. A healthy blood-brain barrier (BBB) plays a crucial role in guarding the brain against elevated levels of blood glutamate, making its permeability a vital aspect of glutamate regulation within the brain. Studies have shown the efficacy of reducing excess glutamate in the brain as a treatment for post-TBI depression, anxiety, and aggression. The purpose of this article is to evaluate the involvement of dietary glutamate in the development of depression after TBI. We performed a literature search to examine the effects of diets abundant in glutamate, which are common in Asian populations, when compared to diets low in glutamate, which are prevalent in Europe and America. We specifically explored these effects in the context of chronic BBB damage after TBI, which may initiate neurodegeneration and subsequently have an impact on depression through the mechanism of chronic glutamate neurotoxicity. A glutamate-rich diet leads to increased blood glutamate levels when contrasted with a glutamate-poor diet. Within the context of chronic BBB disruption, elevated blood glutamate levels translate to heightened brain glutamate concentrations, thereby intensifying neurodegeneration due to glutamate neurotoxicity.

Using normative modeling and machine learning for detecting mild traumatic brain injury from magnetoencephalography data

New biomarkers are urgently needed for many brain disorders; for example, the diagnosis of mild traumatic brain injury (mTBI) is challenging as the clinical symptoms are diverse and nonspecific. EEG and MEG studies have demonstrated several population-level indicators of mTBI that could serve as objective markers of brain injury. However, deriving clinically useful biomarkers for mTBI and other brain disorders from EEG/MEG signals is hampered by the large inter-individual variability even across healthy people. Here, we used a multivariate machine-learning approach to detect mTBI from resting-state MEG measurements. To address the heterogeneity of the condition, we employed a normative modeling approach and modeled MEG signal features of individual mTBI patients as deviations with respect to the normal variation. To this end, a normative dataset comprising 621 healthy participants was used to determine the variation in power spectra across the cortex. In addition, we constructed normative datasets based on age-matched subsets of the full normative data. To discriminate patients from healthy control subjects, we trained support-vector-machine classifiers on the quantitative deviation maps for 25 mTBI patients and 20 controls not included in the normative dataset. The best performing classifier made use of the full normative data across the entire age and frequency ranges. This classifier was able to distinguish patients from controls with an accuracy of 79%. Inspection of the trained model revealed that low-frequency activity in the theta frequency band (4-8 Hz) is a significant indicator of mTBI, consistent with earlier studies. The results demonstrate the feasibility of using normative modeling of MEG data combined with machine learning to advance diagnosis of mTBI and identify patients that would benefit from treatment and rehabilitation. The current approach could be applied to a wide range of brain disorders, thus providing a basis for deriving MEG/EEG-based biomarkers.

Network analysis applied to post-concussion symptoms in two mild traumatic brain injury samples

Objective

A latent disease explanation cannot exclusively explain post-concussion symptoms after mild traumatic brain injury (mTBI). Network analysis offers an alternative form of explanation for relationships between symptoms. The study aimed to apply network analysis to post-concussion symptoms in two different mTBI cohorts; an acute treatment-seeking sample and a sample 10 years post-mTBI.

Method

The treatment-seeking sample (n = 258) were on average 6 weeks post-injury; the 10 year post mTBI sample (n = 193) was derived from a population-based incidence and outcomes study (BIONIC). Network analysis was completed on post-concussion symptoms measured using the Rivermead Post-Concussion Questionnaire.

Results

In the treatment-seeking sample, frustration, blurred vision, and concentration difficulties were central to the network. These symptoms remained central in the 10 year post mTBI sample. A Network Comparison Test revealed evidence of a difference in network structure across the two samples (p = 0.045). However, the only symptoms that showed significant differences in strength centrality across samples were irritability and restlessness.

Conclusion

The current findings suggest that frustration, blurred vision and concentration difficulties may have an influential role in the experience and maintenance of post-concussion symptoms. The impact of these symptoms may remain stable over time. Targeting and prioritising the management of these symptoms may be beneficial for mTBI rehabilitation.

Inflammatory cytokines associated with mild traumatic brain injury and clinical outcomes: a systematic review and meta-analysis

Mild traumatic brain injuries (mTBIs) trigger a neuroinflammatory response, which leads to perturbations in the levels of inflammatory cytokines, resulting in a distinctive profile. A systematic review and meta-analysis were conducted to synthesize data related to levels of inflammatory cytokines in patients with mTBI. The electronic databases EMBASE, MEDLINE, and PUBMED were searched from January 2014 to December 12, 2021. A total of 5,138 articles were screened using a systematic approach based on the PRISMA and R-AMSTAR guidelines. Of these articles, 174 were selected for full-text review and 26 were included in the final analysis. The results of this study demonstrate that within 24 hours, patients with mTBI have significantly higher levels of Interleukin-6 (IL-6), Interleukin-1 Receptor Antagonist (IL-1RA), and Interferon-γ (IFN-γ) in blood, compared to healthy controls in majority of the included studies. Similarly one week following the injury, patients with mTBI have higher circulatory levels of Monocyte Chemoattractant Protein-1/C-C Motif Chemokine Ligand 2 (MCP-1/CCL2), compared to healthy controls in majority of the included studies. The results of the meta-analysis also confirmed these findings by demonstrating significantly elevated blood levels of IL-6, MCP-1/CCL2, and Interleukin-1 beta (IL-1β) in the mTBI population compared to healthy controls (p < 0.0001), particularly in the acute stages (<7 days). Furthermore, it was found that IL-6, Tumor Necrosis Factor-alpha (TNF-α), IL-1RA, IL-10, and MCP-1/CCL2 were associated with poor clinical outcomes following the mTBI. Finally, this research highlights the lack of consensus in the methodology of mTBI studies that measure inflammatory cytokines in the blood, and also provides direction for future mTBI research.

Reconceptualizing Recovery After Concussion: A Phenomenological Exploration of College Student Experiences

PURPOSE

Typical measures of recovery from concussion-such as symptom scales, neurocognitive testing, or exertion measures-may not capture individualized experiences of concussion. This report examines how college students with concussion interact with and consider their recovery.

METHOD

Sixteen college students who sustained concussions while in college completed 40- to 75-min semistructured interviews. All were enrolling to become mentors in a peer mentoring program for students with concussion. Questions addressed experiences as a college student with concussion, life changes following concussion, and role of peers in recovery. Using phenomenological reduction, analysis focused on the phenomenon of recovery and motivation for participation in a mentoring program.

RESULTS

Two main themes were found: (a) What Recovery Looks Like and (b) Gaining Perspective, Learning to Cope and Adapting to Change. Thirteen participants denied the label of "recovered" even though all had been deemed recovered and discharged from medical care. Instead, two subthemes emerged within What Recovery Looks Like: Ongoing Recovery and Reconceptualizing Recovery. Perceptions of recovery were influenced by effort, capacity, and resilience. In the second theme, students described strategies, resources, and supports used to cope with their injuries; most commonly used was emotion-focused coping.

CONCLUSIONS

College students with concussion consider recovery as an ongoing process rather than a dichotomized condition. Student experiences may not be reflected in commonly used symptom scales or objective assessments.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.21084925.

Diffusion-Weighted Imaging in Mild Traumatic Brain Injury: A Systematic Review of the Literature

There is evidence that diffusion-weighted imaging (DWI) is able to detect tissue alterations following mild traumatic brain injury (mTBI) that may not be observed on conventional neuroimaging; however, findings are often inconsistent between studies. This systematic review assesses patterns of differences in DWI metrics between those with and without a history of mTBI. A PubMed literature search was performed using relevant indexing terms for articles published prior to May 14, 2020. Findings were limited to human studies using DWI in mTBI. Articles were excluded if they were not full-length, did not contain original data, if they were case studies, pertained to military populations, had inadequate injury severity classification, or did not report post-injury interval. Findings were reported independently for four subgroups: acute/subacute pediatric mTBI, acute/subacute adult mTBI, chronic adult mTBI, and sport-related concussion, and all DWI acquisition and analysis methods used were included. Patterns of findings between studies were reported, along with strengths and weaknesses of the current state of the literature. Although heterogeneity of sample characteristics and study methods limited the consistency of findings, alterations in DWI metrics were most commonly reported in the corpus callosum, corona radiata, internal capsule, and long association pathways. Many acute/subacute pediatric studies reported higher FA and lower ADC or MD in various regions. In contrast, acute/subacute adult studies most commonly indicate lower FA within the context of higher MD and RD. In the chronic phase of recovery, FA may remain low, possibly indicating overall demyelination or Wallerian degeneration over time. Longitudinal studies, though limited, generally indicate at least a partial normalization of DWI metrics over time, which is often associated with functional improvement. We conclude that DWI is able to detect structural mTBI-related abnormalities that may persist over time, although future DWI research will benefit from larger samples, improved data analysis methods, standardized reporting, and increasing transparency.

Fear avoidance and return to work after mild traumatic brain injury

OBJECTIVES

Fear avoidance is associated with symptom persistence after mild traumatic brain injury (mTBI). In this study, we investigated whether fear avoidance was associated with other outcomes such as return to work-related activity (RTW).

MATERIALS AND METHODS

We analyzed associations between fear avoidance and RTW 6-9 months after mTBI, in two merged prospective mTBI cohorts. Adult participants aged 16 or over (n=175), presenting to outpatient services in New Zealand within 3 months of their injury, who were engaged in work-related activity at the time of injury, were included. Participants completed the Fear Avoidance Behavior after Traumatic Brain Injury (FAB-TBI) questionnaire at enrollment and 6 months later. Associations between FAB-TBI scores and RTW outcome were analyzed using multivariate approaches.

RESULTS

Overall, 53% of participants had RTW by 6-9 months after mTBI. While early fear avoidance was weakly associated with RTW, persistent high fear avoidance between study assessments or increasing avoidance with time were associated with greater odds of still being off work 6-9 months after injury.

CONCLUSIONS

Pervasive and increasing avoidance of symptom triggers after mTBI were associated with lower rates of RTW 6-9 months after mTBI. Further research is needed to better understand transition points along the recovery trajectory where fear avoidance behaviors fade or increase after mTBI.

Relationship between psychosocial and psychiatric risk factors and poor long-term outcome following mild traumatic brain injury: A systematic review

BACKGROUND AND PURPOSE

Mild traumatic brain injury (mTBI) has an estimated worldwide incidence of >60 million per year, and long-term persistent postconcussion symptoms (PPCS) are increasingly recognized as being predicted by psychosocial variables. Patients at risk for PPCS may be amenable to closer follow-up to treat modifiable symptoms and prevent chronicity. In this regard, similarities seem to exist with psychosocial risk factors for chronicity in other health-related conditions. However, as opposed to other conditions, no screening instruments exist for mTBI.

METHODS

A systematic search of the literature on psychological and psychiatric predictors of long-term symptoms in mTBI was performed by two independent reviewers using PubMed, Embase, and Web of Science.

RESULTS

Fifty papers were included in the systematic analysis. Anxiety, depressive symptoms, and emotional distress early after injury predict PPCS burden and functional outcome up to 1 year after injury. In addition, coping styles and preinjury psychiatric disorders and mental health also correlate with PPCS burden and functional outcome. Associations between PPCS and personality and beliefs were reported, but either these effects were small or evidence was limited.

CONCLUSIONS

Early psychological and psychiatric factors may negatively interact with recovery potential to increase the risk of chronicity of PPCS burden after mTBI. This opens opportunities for research on screening tools and early intervention in patients at risk.

The incidence and severity of symptoms similiar to peristing concussion symptoms in neurologically healthy individuals in aotearoa New Zealand

The non-specificity of persisting concussion symptoms (PCS) following concussion can make treatment and rehabilitation a complex and challenging endeavour for clinicians. International studies have demonstrated that in neurologically healthy individuals similar symptoms also exist. This study aimed to examine the presence and frequency of symptoms similar to PCS in neurologically healthy adults in Aotearoa New Zealand and compare these to PCS following concussion. 252 neurologically healthy adults (34.22 years); completed the Rivermead Post-Concussion Questionnaire (RPQ). Scores on this measure were evaluated and compared with 146 individuals who were at least three months post-injury (34.62 years). 25.79% (n = 65) of the neurologically healthy individuals had scores on the RPQ of ≥16. Fatigue was the most commonly endorsed symptom (67.9%), followed by sleep disturbances (59.9%). Certain demographic factors (age, education history and gender) were associated with higher endorsement but only on specific symptoms. The concussion group had significantly higher scores on the RPQ and significantly more individuals with PCS. However, at the individual item level, just over half of PCS symptoms were significantly higher in the concussion group. These symptoms were predominately neurological, with only forgetfulness and irritability significantly different between the concussion and neurologically healthy groups. Symptoms similar to PCS are prevalent in neurologically healthy individuals in Aotearoa New Zealand. The implications of these findings on the rehabilitation and management of PCS are discussed.

The importance of screening for functional neurological disorders in patients with persistent post-concussion symptoms

BACKGROUND

Functional neurological disorder (FND) may commonly co-occur with persistent symptoms following a psychological trauma or physical injury such as concussion.

OBJECTIVE

To explore the occurrence of FND in a population with persistent post-concussion symptoms (PPCS) and the associations between FND and depression as well as anxiety in participants with PPCS.

METHODS

Sixty-three individuals with PPCS presenting to a specialized brain injury clinic completed the following questionnaires: screening for somatoform disorder conversion disorder subscale (SOM-CD), Rivermead post-concussion symptom questionnaire (RPQ), patient health questionnaire-9 (PHQ-9), and generalized anxiety disorder questionnaire- 7 (GAD-7). Both multiple linear regression and logistic regression were conducted to evaluate the relationship between questionnaires and adjust for covariates.

RESULTS

We found that total RPQ score (βˆ= 0.27; 95% CI = [0.16, 0.38]), GAD-7 score (βˆ= 0.71; 95% CI = [0.50, 0.92]) and PHQ-9 score (βˆ= 0.54; 95% CI = [0.32, 0.76]) were positively associated with SOM-CD score individually, after consideration of other covariates. Participants meeting the criteria for severe FND symptoms were 4.87 times more likely to have high PPCS symptom burden (95% CI = [1.57, 22.84]), 8.95 times more likely to have severe anxiety (95% CI = [3.31, 35.03]) and 4.11 times more likely to have severe depression symptom burden (95% CI = [1.77, 11.53]).

CONCLUSION

The findings of this study indicate an association between FND and post-concussion symptoms as well as an association between FND and symptoms of depression and anxiety in patients with PPCS. Patients with PPCS should be screened for FND to provide a more targeted treatment approach that includes somatic-focused interventions.

A comparison of diffusion tensor imaging tractography and constrained spherical deconvolution with automatic segmentation in traumatic brain injury

Detection of microstructural white matter injury in traumatic brain injury (TBI) requires specialised imaging methods, of which diffusion tensor imaging (DTI) has been extensively studied. Newer fibre alignment estimation methods, such as constrained spherical deconvolution (CSD), are better than DTI in resolving crossing fibres that are ubiquitous in the brain and may improve the ability to detect microstructural injuries. Furthermore, automatic tract segmentation has the potential to improve tractography reliability and accelerate workflow compared to the manual segmentation commonly used. In this study, we compared the results of deterministic DTI based tractography and manual tract segmentation with CSD based probabilistic tractography and automatic tract segmentation using TractSeg. 37 participants with a history of TBI (with Glasgow Coma Scale 13-15) and persistent symptoms, and 41 healthy controls underwent deterministic DTI-based tractography with manual tract segmentation and probabilistic CSD-based tractography with TractSeg automatic segmentation.Fractional anisotropy (FA) and mean diffusivity of corpus callosum and three bilateral association tracts were measured. FA and MD values derived from both tractography methods were generally moderately to strongly correlated. CSD with TractSeg differentiated the groups based on FA, while DTI did not. CSD and TractSeg-based tractography may be more sensitive in detecting microstructural changes associated with TBI than deterministic DTI tractography. Additionally, CSD with TractSeg was found to be applicable at lower b-value and number of diffusion-encoding gradients data than previously reported.

Depressive Symptoms in Individuals With Persistent Postconcussion Symptoms: A Systematic Review and Meta-Analysis

IMPORTANCE

Approximately 15% to 30% of individuals with a history of concussion present with persistent postconcussion symptoms (PPCS). Individuals with PPCS are at greater risk of experiencing depressive symptoms.

OBJECTIVE

To synthesize the association between depressive symptoms and PPCS in children, adolescents, and adults via meta-analysis and to investigate potential moderators of that association.

DATA SOURCES

Systematic search of Ovid Medline, CINAHL, PsycInfo, and Embase from 1995 to January 2022 was performed. Additionally, references from included studies were hand-searched to ensure relevant articles were captured in the search.

STUDY SELECTION

Studies that involved participants who experienced PPCS and quantified depressive symptoms were included. The definition of PPCS was limited to physician-diagnosed or self-reported concussion, with symptoms lasting for a minimum of 4 weeks postinjury. Two authors independently screened all articles to determine study eligibility.

DATA EXTRACTION AND SYNTHESIS

Study characteristics were extracted independently by 2 trained investigators. Study data were meta-analyzed using a random-effects meta-analysis.

EXPOSURE

PPCS.

MAIN OUTCOMES AND MEASURES

The the primary outcome was depressive symptoms.

RESULTS

Data were extracted from 18 studies with a total of 9101 participants. Of the 18 studies, all were cohort studies, and 13 (72%) comprised adult populations. The mean (SD) time since concussion was 21.3 (18.7) weeks. After accounting for potential publication bias, the random-effects meta-analysis found a significant positive association between PPCS and depressive symptoms, (odds ratio, 4.56; 95% CI, 2.82-7.37; P < .001). There were no significant moderators, likely due to the small number of studies included.

CONCLUSIONS AND RELEVANCE

In this meta-analysis, experiencing PPCS was associated with a higher risk of experiencing depressive symptoms. There are several important clinical and health policy implications of the findings. Most notably, the development of strategies for effective prevention and earlier intervention to optimize mental health recovery following a concussion should be supported.

APOE & BDNF polymorphisms interact to affect memory performance at baseline in adolescent athletes

Although several single-nucleotide polymorphisms have been associated with cognitive functioning in a variety of healthy and clinical samples, the influence of gene × gene interactions on cognition is poorly understood. The purpose of this study was to examine interactive relationships between apolipoprotein E (APOE) and brain-derived neurotrophic factor (BDNF) polymorphisms on cognitive functioning in a sample of healthy adolescent athletes. Participants of this cross-sectional study included 78 student-athletes (52.6% male; age: M = 13.31, SD = 1.23). Athletes completed the Immediate Post-Concussion and Cognitive Testing (ImPACT) computerized battery at baseline. APOE and BDNF genotypes were determined with buccal samples (APOE ε4+: n = 26; APOE ε4-: n = 52; BDNF Met+: n = 23; BDNF Met-: n = 55). Two-way analyses of variance (ANOVAs) were used to evaluate the associations among APOE (ε4+ vs. ε4-) and BDNF (Met+ vs. Met-) genotypes and the ImPACT cognitive composites and two-factor model. No main effects were observed for either APOE or BDNF genotypes across the cognitive outcomes. However, there was a significant APOE × BDNF genotype interaction for the verbal (p=.009, η_p²=.091) and visual (p = .012, η_p²=.082) memory composites and the memory factor (p = .001, η_p²=.133), such that ε4+/Met+ carriers demonstrated poorer performance relative to other allele combinations. No significant interactions were observed for the visual motor speed (p = .263, η_p²=.017) or reaction time (p = .825, η_p²=.001) composites or the speed factor (p = .205, η_p²=.022). Our findings suggest an important relationship between APOE and BDNF genotypes on verbal and visual memory performance in healthy adolescent athletes. Clinicians may use this information to offer individualized concussion management based on individual athlete characteristics related to genetics and cognition.

Post-Concussion Symptoms Rule: Derivation and Validation of a Clinical Decision Rule for Early Prediction of Persistent Symptoms after a Mild Traumatic Brain Injury

Mild traumatic brain injury (mTBI) is a common problem. Depending on diagnostic criteria, 13 to 62% of those patients develop persistent post-concussion symptoms (PPCS). The main objective of this prospective multi-center study is to derive and validate a clinical decision rule (CDR) for the early prediction of PPCS. Patients aged ≥14 years were included if they presented to one of our seven participating emergency departments (EDs) within 24 h of an mTBI. Clinical data were collected in the ED, and symptom evolution was assessed at 7, 30 and 90 days post-injury using the Rivermead Post-Concussion Questionnaire (RPQ). The primary outcome was PPCS at 90 days after mTBI. A predictive model called the Post-Concussion Symptoms Rule (PoCS Rule) was developed using the methodological standards for CDR. Of the 1083 analyzed patients (471 and 612 for the derivation and validation cohorts, respectively), 15.6% had PPCS. The final model included the following factors assessed in the ED: age, sex, history of prior TBI or mental health disorder, headache in ED, cervical sprain and hemorrhage on computed tomography. The 7-day follow-up identified additional risk factors: headaches, sleep disturbance, fatigue, sensitivity to light, and RPQ ≥21. The PoCS Rule had a sensitivity of 91.4% and 89.6%, a specificity of 53.8% and 44.7% and a negative predictive value of 97.2% and 95.8% in the derivation and validation cohorts, respectively. The PoCS Rule will help emergency physicians quickly stratify the risk of PPCS in mTBI patients and better plan post-discharge resources.

Exploring the measurement of pediatric cognitive-communication disorders in traumatic brain injury research: A scoping review

OBJECTIVE

To synthesize information about the constructs measured, measurement instruments used, and the timing of assessment of cognitive-communication disorders (CCDs) in pediatric traumatic brain injury (TBI) research.

METHODS AND PROCEDURES

Scoping review conducted in alignment with Arksey and O'Malley's five-stage methodological framework and reported per the PRISMA extension for Scoping Reviews. Inclusion criteria: (a) cohort description, case-control, and treatment studies; (b) participants with TBI aged 5-18 years; (c) communication or psychosocial outcomes; and (d) English full-text journal articles. The first author reviewed all titles, abstracts, and full-text articles; 10% were independently reviewed.

OUTCOMES AND RESULTS

Following screening, a total of 687 articles were included and 919 measurement instruments, measuring 2134 unique constructs, were extracted. The Child Behavior Checklist was the most used measurement instrument and 'Global Outcomes/Recovery' was the construct most frequently measured. The length of longitudinal monitoring ranged between ≤3 months and 16 years.

CONCLUSIONS AND IMPLICATIONS

We found considerable heterogeneity in the constructs measured, the measurement instruments used, and the timing of CCD assessment in pediatric TBI research. A consistent approach to measurement may support clinical decision-making and the efficient use of data beyond individual studies in systematic reviews and meta-analyses.

Interdisciplinary Rehabilitation for Concussion Recovery (i-RECOveR): protocol of an investigator-blinded, randomised, case series with multiple baseline design to evaluate the feasibility and preliminary efficacy of a 12-week treatment for persistent post-concussion symptoms

BACKGROUND

Up to 25% of concussed individuals experience persistent post-concussion symptoms (PPCSs) which may interfere with the return to pre-injury activities and cause significant stress. Given that multiple etiological factors are thought to contribute to PPCSs, an interdisciplinary approach is recommended. This pilot study aims to primarily investigate the feasibility of a novel interdisciplinary treatment for PPCSs. Given this intervention is novel, uncertainty exists in terms of potential recruitment and retention rates, adverse events, and treatment adherence and fidelity. These factors will be explored to inform the feasibility of a phase-2 randomised controlled trial. Preliminary efficacy of this intervention will also be explored.

METHODS

Fifteen individuals with mild traumatic brain injury and PPCSs will receive up to 12 weeks of interdisciplinary treatments including psychology, physiotherapy, and medical interventions. Primary feasibility outcomes including data on recruitment and retention rates and treatment adherence will be explored descriptively. The cognitive therapy rating scale will be used to assess treatment fidelity. A single-case series with multiple baseline design will be used to explore preliminary efficacy. Participants will be randomly assigned to baseline phases of 2, 4, or 6 weeks. Regarding patient-centred secondary outcomes, the Rivermead Post-Concussion Symptoms Questionnaire will be assessed three times a week during baseline and treatment phases. Secondary outcomes also include measures of mood, sleep and fatigue, physical functioning, return to activity, and health-related quality of life. Patient-centred outcomes will be assessed at baseline, pretreatment, post-treatment, and one- and three-month follow-up. Thematic analysis of participant experiences will be explored through qualitative interviews.

DISCUSSION

Results from this trial will inform the feasibility and preliminary efficacy of this interdisciplinary concussion intervention and whether proceeding to a future definitive phase-2 randomised controlled trial is worthwhile. Understanding the end-user perspective of the treatment will also enable modifications to the treatment protocol for future trials to best suit the needs of individuals with PPCSs after mTBI. Outcomes from this trial can be directly translated into community rehabilitation programmes.

TRIAL REGISTRATION

ANZCTR, ACTRN12620001111965. Registered 27 October 2020, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=379118.

Psychological flexibility moderates the influence of fear avoidance on outcomes after mild traumatic brain injury

OBJECTIVES

Psychological factors contribute to poorer long-term outcomes following mild traumatic brain injury (mTBI); however, the exact psychological mechanisms that underly this relationship are not well understood. This study examined the relationship between psychological flexibility, fear avoidance, and outcomes over the first 6 months after mTBI.

METHOD

Adults with mTBI-completed measures of psychological flexibility, fear avoidance, post-concussion symptoms, and functional status at baseline (<3 months post-injury; N = 152), and 3-month (N = 133) and 6-month follow-up (N = 102). A conceptually derived moderation-mediation analysis was used to test the mediating effect of fear avoidance on post-concussion symptoms and functional outcomes, and the moderating effects of psychological flexibility on fear avoidance.

RESULTS

Fear avoidance had a significant indirect effect on the relationship between post-concussion symptoms and functional status across all three time points. Psychological flexibility was found to significantly moderate these effects. Only low levels of psychological flexibility had a significant influence on the mediating effects of high fear avoidance on functional status at 6-month follow-up.

CONCLUSIONS

Psychological flexibility may influence mTBI recovery by exerting an influence on fear avoidance. These initial findings provide a potential theoretical explanation of how fear avoidance can become maladaptive with time after mTBI.

Comparability of (Post-Concussion) Symptoms across Time in Individuals after Traumatic Brain Injury: Results from the CENTER-TBI Study

Post-concussion symptoms often occur after TBI, persist and cause disabilities. The Rivermead Post-Concussion Symptoms Questionnaire (RPQ) is widely used in this population, but little is known about the comparability of the symptoms over time, i.e., longitudinal measurement invariance (MI). The objectives of this study were to analyze the longitudinal MI of RPQ symptoms from three to twelve months after TBI and to find factors related to RPQ symptoms. The study involved 1023 individuals after TBI who took part in the Collaborative European NeuroTrauma Effectiveness Research in TBI (CENTER-TBI) study and completed the RPQ at three, six and twelve months post-injury. Longitudinal confirmatory factor analysis showed that the three-factor structure (somatic, emotional and cognitive) remains stable within one year after TBI. Linear mixed models revealed that sex, injury cause and prior psychiatric problems were related to the RPQ three-factor structure as well as to the RPQ total score. The study strengthens evidence for the RPQ’s factorial structure stability within one year after TBI and identifies sex, injury cause and prior psychiatric problems as important factors that may help clinicians to prevent future complications of symptomatology after TBI.

Acute Effects of Concussion in Adolescent Athletes With High Preseason Anxiety

OBJECTIVE

To examine associations between pre-existing anxiety symptoms, and symptoms and cognitive functioning acutely following a suspected concussion.

DESIGN

Nested case-control study.

SETTING

High schools in Maine, USA.

PARTICIPANTS

Participants were identified from a dataset of 46 920 student athletes ages 13 to 18 who received baseline preseason testing. A subset of 4732 underwent testing following a suspected concussion. Of those, 517 were assessed within 72 hours after their suspected concussion and met other inclusion criteria. Nineteen injured athletes endorsed anxiety-like symptoms on the Post-Concussion Symptom Scale (PCSS) during baseline testing and were placed in the high anxiety group. Each athlete was matched to 2 injured athletes who did not endorse high levels of anxiety-like symptoms (N = 57).

MAIN OUTCOME MEASURES

Immediate Post-Concussion Assessment and Cognitive Testing cognitive composite scores, PCSS total score, and symptom endorsement.

RESULTS

Cognitive composite scores were similar between groups across testing times ( = 0.004-0.032). The high anxiety group endorsed a greater number of symptoms than the low anxiety group ( = 0.452) and rated symptoms as more severe ( = 0.555) across testing times. Using a modified symptom score that excluded anxiety-like symptoms, a mixed analysis of variance indicated a group by injury interaction ( = 0.079); the high anxiety group reported greater increases in overall symptom severity following injury.

CONCLUSIONS

Adolescent athletes who have an anxious profile at baseline are likely to experience greater symptom burden following injury. Consideration of pre-injury anxiety may inform clinical concussion management by tailoring intervention strategies (eg, incorporating mental health treatments) to facilitate concussion recovery.

Alwyn Lishman's contribution to the neuropsychiatry of head injury (traumatic brain injury); two key papers

INTRODUCTION

Alwyn Lishman appreciated that if we are to understand the psychological consequences of cerebral disorder we must study the interaction between organic disease and psychological processes.

METHODS

We have reviewed Lishman's two major publications on the neuropsychiatry of head injury, published in 1968 and 1988, and considered their conclusions in the light of current knowledge.

RESULTS

In his 1968 paper on the psychiatric sequelae of open head injuries sustained in World War II Lishman demonstrated associations between the type of psychiatric sequelae and the location of the injury. He also found that those with "somatic complaints", such as fatigue or sensitivity to light, showed less evidence of organic injury. In his 1988 paper, he attempted to explain why a mild head injury may be followed by long-lasting symptoms. He suggested that in the absence of complications early, organic, symptoms (physiogenesis) should recover quickly. However, this healthy recovery could be jeopardised by psychological factors (psychogenesis), resulting in long-lasting symptoms. This model of physiogenesis and psychogenesis remains relevant today.

CONCLUSIONS

The ideas Lishman developed in these two papers were the basis for his huge contribution to the field of neuropsychiatry, and remain relevant today.

Reframing postconcussional syndrome as an interface disorder of neurology, psychiatry and psychology

Persistent symptoms following a minor head injury can cause significant morbidity, yet the underlying mechanisms for this are poorly understood. The shortcomings of the current terminology that refer to non-specific symptom clusters is discussed. This update considers the need for a multi-dimensional approach for the heterogenous mechanisms driving persistent symptoms after mild traumatic brain injury. Relevant pathophysiology is discussed to make the case for mild traumatic brain injury to be conceptualized as an interface disorder spanning neurology, psychiatry and psychology. The relevance of pre-injury factors, psychological co-morbidities and their interaction with the injury to produce persistent symptoms are reviewed. The interplay with psychiatric diagnoses, functional and somatic symptom disorder presentations and the influence of the medicolegal process is considered. The judicious use and interpretation of investigations given the above complexity is discussed, with suggestions of how the explanation of the diagnostic formulation to the patient can be tailored, including insight into the above processes, to aid recovery. Moving beyond the one-dimensional concept of 'postconcussional syndrome' and reframing the cause of persistent symptoms following mild traumatic brain injury in a bio-psycho-socio-ecological model will hopefully improve understanding of the underlying contributory mechanistic interactions and facilitate treatment.

Perceived Injustice After Mild Traumatic Brain Injury

OBJECTIVE

To examine perceived injustice and its associations with self-reported symptoms and return to work at 3 months after injury in a prospectively recruited sample of patients with mild traumatic brain injury (mTBI).

DESIGN

Observational study.

SETTING

TBI outpatient unit.

PARTICIPANTS

Adult patients aged 18 to 68 years with mTBI (n = 100) or orthopedic injury ([OI]; n = 34).

MAIN MEASURES

The Injustice Experience Questionnaire (IEQ) and its associations with the Rivermead Post Concussion Questionnaire (RPQ), Beck Depression Inventory-Second Edition (BDI-II), PTSD Checklist-Civilian Version (PCL-C), and Pain Visual Analog Scale (PVAS). Information on injury-related characteristics, compensation seeking and litigation, and return-to-work status was also collected.

RESULTS

Median IEQ total score was 3 (range, 0-23) in the mTBI group and 2.5 (range, 0-25) in the OI group. In the mTBI group, IEQ was significantly correlated with RPQ (rs = 0.638, P < .01), BDI-II (rs = 0.612, P < .01), PCL-C (rs = 0.679, P < .01), and PVAS (rs = 0.232, P < .05). The association between IEQ and PCL-C (rs =0.797, P < .01) and BDI-II (rs = 0.395, P < .05) was also found in the OI group. In both groups, patients who were still on sick leave at 3 months after injury tended to report higher perceived injustice (IEQ total score) than patients who had returned to work or studies. However, this difference did not reach statistical significance.

CONCLUSIONS

Perceived injustice is associated with self-reported symptoms in patients with mTBI. Our results suggest that perceived injustice could be a relevant construct to consider in clinical management of patients with mTBI. Also, perceived injustice could be a potential target for psychological interventions promoting recovery after mTBI.

Mental Health Outcomes Across the Lifespan in Individuals With Persistent Post-Concussion Symptoms: A Scoping Review

Objective:

Concussion is a common yet heterogenous injury. Approximately 15–30% of cases present with persistent post-concussion symptoms (PPCS), continuing 4 weeks or more post-injury in children, youth, and adolescents, and 3 months or more in adults. There are known bidirectional links between PPCS and mental health outcomes. The focus of this scoping review is to explore the literature on mental health outcomes in individuals experiencing PPCS. Research objectives were to explore: (1) the mental health outcomes of individuals with PPCS and types of assessments used to identify mental health outcomes this group, and (2) how mental health outcomes compare in terms of similarities and differences among pediatric and adult populations with PPCS.

Method

Ovid MEDLINE; EMBASE; CINAHL, and PsycInfo databases were searched. After title and abstract screening of 11,920 studies, 481 articles were reviewed. Twenty-five papers met inclusion criteria. Results were organized by mental health outcomes of pediatric and adult populations, separately.

Results

There was a significantly higher number of studies devoted to adult populations. Of the 25 studies, 19 (76%) focused on adults, while six (24%) focused on adolescents. In adult populations, studies focused on symptoms of: anxiety (n = 2), depression (n = 8), and anxiety and depression (n = 9). Two studies assessed other emotional outcomes (10.5%). Within pediatric populations, an equal number of studies explored symptoms of: anxiety (n = 2), depression (n = 2), and anxiety and depression (n = 2). No studies focused on other emotional outcomes. Studies ranged greatly in methods, design, and control group. Most studies reported higher psychiatric symptoms of anxiety and/or depression in those with PPCS compared to individuals with recovered concussion or healthy controls.

Discussion

This review contributes to the understanding of mental health outcomes in those experiencing PPCS. Mental health and PPCS requires greater attention in pediatric populations, and consider strategies for those experiencing PPCS and mental health impacts. Future studies should consider including a wider range of emotional outcomes in their design, not limited to anxiety and depression. Study results may lead to improvements and research in the identification, assessment, and management of PPCS and mental health.

The effect of transcranial direct current stimulation on cognitive performance in youth with persistent cognitive symptoms following concussion: a controlled pilot study

OBJECTIVE

Explore the feasibility, tolerability, and early efficacy of transcranial direct current stimulation (tDCS) as a therapeutic intervention for youth with cognitive persistent post-concussion symptoms (PPCS).

HYPOTHESIS

tDCS improves performance on a dual task working memory (WM) paradigm in youth with cognitive PPCS.

PARTICIPANTS

Twelve youth experiencing cognitive PPCS.

DESIGN

A quasi-randomized pilot trial was used to explore the tolerability of, and performance differences on, a dual N-Back WM task paired with active or sham tDCS over 3 sessions.

MEASURES

Accuracy and reaction time on WM task and self-report of tDCS tolerability.

RESULTS

Trends toward increases in accuracy from Day 1 to 3 seen in both groups. Active tDCS group performed better than sham on Day 2 in N-Back level N2 (p = .019), and marginally better than the sham group on Day 3 in level N3 (p = .26). Participants reported tDCS as tolerable; compared to the active tDCS group, the sham group reported more "considerable" (p = .078) and "strong" symptoms (p = .097).

CONCLUSION

tDCS is a promising tool for enhancing WM performance and is a feasible and tolerable adjunct to behavioral interventions in youth with cognitive PPCS. A clinical trial to demonstrate efficacy is warranted.

Exploring Heterogeneity of Stepped Collaborative Care Treatment Response Trajectories after Adolescent Sports Injury Concussion

Objective: Few clinical trials of posttraumatic interventions have utilized symptom trajectory modeling to explore heterogeneity of treatment responses. The goal of this investigation was to conduct a secondary analysis of a randomized clinical trial of stepped collaborative care for adolescents with sports and recreational related concussion and persistent symptoms of >1 month.Method: Trajectory modeling was used to examine the impact of randomization to the intervention as well as demographic, clinical, and injury characteristics on adolescent post-concussive symptom trajectories. Two hundred male and female adolescents were assessed >1 month after a concussion, and then 3-, 6- and 12-months later with a standardized measure of concussive symptoms, the Health and Behavior Inventory (HBI). Multinomial logistic regression was used to compare the association between intervention, demographic, clinical and injury characteristics with trajectory group membership.Results: Four post-concussive symptom trajectories emerged: recovery, remitting, low-persistent, and high-persistent. In adjusted analyses randomization to the intervention condition was associated with significantly greater odds of HBI recovery trajectory group membership (OR 3.29 95% CI 1.06-10.28). Female gender and prior concussion history were associated with significantly greater odds of high-persistent trajectory group membership relative to all other trajectories. Greater odds of high-persistent versus recovery group trajectory membership was observed for adolescents with a pre-injury history of anxiety and/or depressive disorders.Conclusions: Stepped collaborative care was associated with an increased odds of recovery versus high-persistent post-concussive symptom trajectories, while readily identifiable baseline characteristics were associated high-persistent symptoms. Future post-concussive clinical trials and practice improvement efforts could incorporate these observations.

Methodology Matters: Comparing Approaches for Defining Persistent Symptoms after Mild Traumatic Brain Injury

Some people experience persistent post-concussion symptoms (PPCS) after mild traumatic brain injury (mTBI). A meaningful clinical classification and scientific progress are hampered by a lack of consensus regarding the phenomenology, assessment, and operationalization of PPCS. Here we demonstrate and evaluate how the methodology used to assess and define persistent symptoms after mTBI influences PPCS as a binary outcome. We present empirical data from 15 classification methods reflecting procedures found in the literature and clinical practice. In total, 221 patients with mTBI, 73 patients with orthopedic injuries, and 77 community controls were included in the study. The prevalence rate of PPCS in the mTBI group varied between 10% and 47%, depending on the method used to assess and define unfavorable outcome. There was generally low positive agreement between the different methods; even the two methods yielding the most similar prevalence rates (89.2% overall proportion agreement) agreed on less than half (45.5% positive agreement) of the PPCS cases. Using a liberal but not uncommon threshold for symptom severity, there was a considerable misclassification rate of PPCS in both comparison groups. Our results highlight the importance for researchers to be aware of the limitations of using binary approaches for classification of PPCS. The poor agreement between methods should be considered when (1) interpreting the heterogeneity in the existing PPCS literature and (2) developing new improved methods. An empirically informed consensus regarding classification of PPCS should be a priority for the research community.

Brain Connectivity Changes in Post-Concussion Syndrome as the Neural Substrate of a Heterogeneous Syndrome

BACKGROUND

Post-concussion syndrome (PCS) or persistent symptoms of concussion refers to a constellation of symptoms that persist for weeks and months after a concussion. To better capture the heterogeneity of the symptoms of patients with post-concussion syndrome, we aimed to separate patients into clinical subtypes based on brain connectivity changes.

METHODS

Subject-specific structural and functional connectomes were created based on Diffusion Weighted and Resting State Functional Magnetic Resonance Imaging, respectively. Following an informed dimensionality reduction, a gaussian mixture model was used on patient specific structural and functional connectivity matrices to find potential patient clusters. For validation, the resulting patient subtypes were compared in terms of cognitive, neuropsychiatric, and post-concussive symptom differences.

RESULTS

Multimodal analyses of brain connectivity were predictive of behavioural outcomes. Our modelling revealed 2 patient subtypes; mild and severe. The severe group showed significantly higher levels of depression, anxiety, aggression, and a greater number of symptoms than the mild patient subgroup.

CONCLUSION

This study suggests that structural and functional connectivity changes together can help us better understand the symptom severity and neuropsychiatric profiles of patients with post-concussion syndrome. This work allows us to move towards precision medicine in concussions and provides a novel machine learning approach that can be applicable to other heterogeneous conditions.

OUP accepted manuscript

OBJECTIVE

The etiology of persistent memory complaints after concussion is poorly understood. Memory perfectionism (highly valuing memory ability and intolerance of minor memory lapses) may help explain why some people report persistent subjective memory problems in the absence of corresponding objective memory impairment. This study investigated the relationship between memory perfectionism and persistent memory complaints after concussion.

METHODS

Secondary analysis of baseline data from a randomized controlled trial. Adults (N = 77; 61% women) with persistent symptoms following concussion were recruited from outpatient specialty clinics. Participants completed the National Institutes of Health Toolbox Cognition Battery, Test of Memory Malingering-Trial 1, and questionnaires measuring memory perfectionism (Metamemory in Adulthood-Achievement subscale), forgetfulness and other postconcussion symptoms (Rivermead Postconcussion Symptoms Questionnaire; RPQ), and depression (Patient Health Questionnaire-2) at M = 17.8 weeks postinjury. Patients with versus without severe memory complaints (based on the RPQ) were compared.

RESULTS

Memory perfectionism was associated cross-sectionally with severe memory complaint, after controlling for objective memory ability, overall cognitive ability, and depression (95% confidence interval for odds ratio = 1.11-1.40). Sensitivity analyses showed that this relationship did not depend on use of specific objective memory tests nor on inclusion of participants who failed performance validity testing. In a control comparison to test the specificity of identified relationships, memory perfectionism was not associated with severe fatigue (95% confidence interval for odds ratio = 0.91-1.07).

CONCLUSIONS

Memory perfectionism may be a risk factor for persistent memory symptoms after concussion, with potential relevance to the spectrum of functional cognitive disorders more broadly.

Diffusion and functional MRI findings and their relationship to behaviour in postconcussion syndrome: a scoping review

Postconcussion syndrome (PCS) is a term attributed to the constellation of symptoms that fail to recover after a concussion. PCS is associated with a variety of symptoms such as headaches, concentration deficits, fatigue, depression and anxiety that have an enormous impact on patients' lives. There is currently no diagnostic biomarker for PCS. There have been attempts at identifying structural and functional brain changes in patients with PCS, using diffusion tensor imaging (DTI) and functional MRI (fMRI), respectively, and relate them to specific PCS symptoms. In this scoping review, we appraised, synthesised and summarised all empirical studies that (1) investigated structural or functional brain changes in PCS using DTI or fMRI, respectively, and (2) assessed behavioural alterations in patients with PCS. We performed a literature search in MEDLINE (Ovid), Embase (Ovid) and PsycINFO (Ovid) for primary research articles published up to February 2020. We identified 8306 articles and included 45 articles that investigated the relationship between DTI and fMRI parameters and behavioural changes in patients with PCS: 20 diffusion, 20 fMRI studies and 5 papers with both modalities. Most frequently studied structures were the corpus callosum, superior longitudinal fasciculus in diffusion and the dorsolateral prefrontal cortex and default mode network in the fMRI literature. Although some white matter and fMRI changes were correlated with cognitive or neuropsychiatric symptoms, there were no consistent, converging findings on the relationship between neuroimaging abnormalities and behavioural changes which could be largely due to the complex and heterogeneous presentation of PCS. Furthermore, the heterogeneity of symptoms in PCS may preclude discovery of one biomarker for all patients. Further research should take advantage of multimodal neuroimaging to better understand the brain-behaviour relationship, with a focus on individual differences rather than on group comparisons.