Chronic traumatic encephalopathy neuropathologic change in former Australian rugby players.

AIMS: We applied the 2021 consensus criteria for both chronic traumatic encephalopathy neuropathological change and traumatic encephalopathy syndrome in a small case series of six former elite-level Australian rugby code players. METHODS: Neuropathological assessment of these cases was carried out at the Sydney and Victorian Brain Banks. Clinical data were collected via clinical interviews and health questionnaires completed by the participants and/or their next of kin, and neuropsychological testing was conducted with participants who were capable of completing this testing. RESULTS: All cases exhibited progressive cognitive impairment during life. Chronic traumatic encephalopathy neuropathological change was identified in four out of the six cases. However, coexisting neuropathologies were common, with limbic-predominant age-related TDP-43 encephalopathy and ageing-related tau astrogliopathy seen in all cases, intermediate or high Alzheimer's disease neuropathological change seen in four cases and hippocampal sclerosis seen in two of the six cases. CONCLUSION: The presence of multiple neuropathologies in these cases complicates clinical diagnostic efforts for traumatic encephalopathy syndrome. It will be important for further clinicopathological studies on larger groups to report all neuropathological comorbidities found in cases diagnosed with either chronic traumatic encephalopathy neuropathological change and/or traumatic encephalopathy syndrome.

Examining for gender differences in return to learn following sport-related concussion in high school student athletes.

OBJECTIVE: Prior studies have investigated associations between gender, symptom resolution, and time to return to play following sport-related concussion (SRC). However, there is a notable gap in research regarding the association between gender and return to learn (RTL) in adolescents. Therefore, this study 1) compared the patterns of RTL between boys and girls who are high school student athletes, and 2) evaluated the possible association between gender and time to RTL after adjusting for covariates. METHODS: A retrospective cohort study of a prospective surveillance program that monitored concussion recovery of athletes in high schools throughout the state of Maine between February 2015 and January 2023 was performed. The primary independent variable was gender, dichotomized as boys and girls. The primary outcome was time to RTL, defined by the number of days for an athlete to return to school without accommodations. Mann-Whitney U-tests were used to compare RTL between the boys and girls. Each athlete's RTL status was dichotomized (i.e., returned vs had not returned) at several time points following injury (i.e., 1, 2, 3, and 4 weeks), and chi-square tests were performed to compare the proportions who achieved RTL between groups. Multivariable linear regression analyses were performed to evaluate the predictive value of gender on RTL. Covariates included age, number of previous concussions, history of learning disability or attention-deficit disorder or attention-deficit/hyperactivity disorder, history of a psychological condition, history of headaches or migraines, initial Sport Concussion Assessment Tool (SCAT3/SCAT5) score, and days to evaluation. RESULTS: Of 895 high school athletes, 488 (54.5%) were boys and 407 (45.5%) were girls. There was no statistically significant difference in median [IQR] days to RTL between genders (6.0 [3.0-11.0] vs 6.0 [3.0-12.0] days; U = 84,365.00, p < 0.375). A greater proportion of boys successfully returned to learn without accommodations by 3 weeks following concussion (93.5% vs 89.4%; χ2 = 4.68, p = 0.030), but no differences were found at 1, 2, or 4 weeks. A multivariable model predicting days to RTL showed that gender was not a significant predictor of RTL (p > 0.05). Longer days to evaluation (ß = 0.10, p = 0.021) and higher initial SCAT3/SCAT5 scores (ß = 0.15, p < 0.001) predicted longer RTL. CONCLUSIONS: In a cohort of high school athletes, RTL did not differ between boys and girls following SRC. Gender was not a significant predictor of RTL. Longer days to evaluation and higher initial symptom scores were associated with longer RTL.

Incidence of surgically treated chronic subdural hematoma after head injury with normal initial computed tomography.

PURPOSE: The objective was to determine the incidence of surgically treated chronic subdural hematoma (cSDH) within six months after head trauma in a consecutive series of head injury patients with a normal initial computed tomography (CT). METHODS: A total of 1941 adult patients with head injuries who underwent head CT within 48 h after injury and were treated at the Tampere University Hospital's emergency department were retrospectively evaluated from medical records (median age = 59 years, IQR = 39-79 years, males = 58%, patients using antithrombotic medication = 26%). Patients with no signs of acute traumatic intracranial pathology or any type of subdural collection on initial head CT were regarded as CT negative (n = 1573, 81%). RESULTS: Two (n = 2) of the 1573 CT negative patients received surgical treatment for cSDH. Consequently, the incidence of surgically treated cSDH after a normal initial head CT during a six-month follow-up was 0.13%. Both patients sustained mild traumatic brain injuries initially. One of the two patients was on antithrombotic medication (warfarin) at the time of trauma, hence incidence of surgically treated cSDH among patients with antithrombotic medication in CT negative patients (n = 376, 23.9%) was 0.27%. Additionally, within CT negative patients, one subdural hygroma was operated shortly after trauma. CONCLUSION: The extremely low incidence of surgically treated cSDH after a normal initial head CT, even in patients on antithrombotic medication, supports the notion that routine follow-up imaging after an initial normal head CT is not indicated to exclude the development of cSDH. Additionally, our findings support the concept of cSDH not being a purely head trauma-related disease.

Treatment of chronic symptoms following mild traumatic brain injury with transcranial LED: a sham run-in pilot study of photobiomodulation therapy.

PRIMARY OBJECTIVE: We evaluated whether photobiomodulation with red/near infrared light applied transcranially via light emitting diodes (LED) was associated with reduced symptoms and improved cognitive functioning in patients with chronic symptoms following mild traumatic brain injury. RESEARCH DESIGN: Participants (3 men, 6 women; 22-61 years-old) underwent a 6-week intervention involving 18 40-minute transcranial LED treatment sessions. METHODS AND PROCEDURES: Reliable change indices were calculated for 10 neuropsychological test scores and 3 self-report questionnaires of subjective cognition, post-concussion symptoms, and depression at baseline and following treatment. Questionnaires were also administered after 2-week sham and at 1-month and 2-month follow-ups. MAIN OUTCOME AND RESULTS: Only 2 participants improved on neuropsychological testing. On questionnaires, 4 reported improved cognition, 5 reported improved post-concussion symptoms, and 3 reported improved depression. Significant improvement in 2 or more domains was reported by 4 participants and mostly maintained at both follow-ups. CONCLUSIONS: Most participants did not improve on neuropsychological testing. A minority self-reported improvement in symptoms, potentially explained by the intervention, psychiatric medication changes, placebo effects, or other factors. Selecting participants with different clinical characteristics, and dosing and delivery system changes, may produce different results. A study design accounting for placebo effects appears warranted in future trials.

Examining Acute Symptoms After Sport-Related Concussion in Collegiate Athletes With Preinjury Migraines.

OBJECTIVE: To examine whether a personal history of migraines is associated with worse acute symptom burden after sport-related concussion (SRC). DESIGN: Retrospective cohort study. SETTING: National Collegiate Athletic Association Division III collegiate programs. PARTICIPANTS: Collegiate athletes from a prospective concussion surveillance system between 09, 2014, and 01, 2023. INTERVENTION: Preinjury migraines (yes/no) were self-reported by athletes. MAIN OUTCOME MEASURES: Post-Concussion Symptom Scale (PCSS) were collected within 3 days postinjury. Mann-Whitney U tests compared total PCSS scores and individual symptom scores between athletes with and without preinjury migraines. Chi-squared tests were used to compare proportions of athletes endorsing individual symptoms (ie, item score ≥1) between 2 groups. Multivariable regression analyzed potential predictors of PCSS scores. RESULTS: Of 1190 athletes with SRC, 93 (7.8%) reported a preinjury history of migraines. No significant difference in total PCSS scores was found between athletes with and without preinjury migraines (22.0 ± 16.4 vs 20.5 ± 15.8, U = 48 719.0, P = 0.471). Athletes with preinjury migraines reported greater severity of "sensitivity to light" (1.59 ± 1.59 vs 1.23 ± 1.41, P = 0.040) and "feeling more emotional" (0.91 ± 1.27 vs 0.70 ± 1.30; P = 0.008) and were more likely to endorse "feeling more emotional" (45.2% vs 29.5%, P = 0.002). No differences were found across all other symptoms, including headaches (migraine = 87.1% vs no migraine = 86.3%, P = 0.835). In a multivariable model, a history of migraine was not a significant predictor of acute PCSS scores, but those with a history of psychological disorders (ß = 0.12, P <0 .001) and greater number of days to symptom evaluation (ß = 0.08, P = 0.005) had higher PCSS scores. CONCLUSIONS: Collegiate athletes with a pre-existing history of migraines did not have higher acute symptom burden after SRC.

The American Congress of Rehabilitation Medicine Diagnostic Criteria for Mild Traumatic Brain Injury.

OBJECTIVE: To develop new diagnostic criteria for mild traumatic brain injury (TBI) that are appropriate for use across the lifespan and in sports, civilian trauma, and military settings. DESIGN: Rapid evidence reviews on 12 clinical questions and Delphi method for expert consensus. PARTICIPANTS: The Mild Traumatic Brain Injury Task Force of the American Congress of Rehabilitation Medicine Brain Injury Special Interest Group convened a Working Group of 17 members and an external interdisciplinary expert panel of 32 clinician-scientists. Public stakeholder feedback was analyzed from 68 individuals and 23 organizations. RESULTS: The first 2 Delphi votes asked the expert panel to rate their agreement with both the diagnostic criteria for mild TBI and the supporting evidence statements. In the first round, 10 of 12 evidence statements reached consensus agreement. Revised evidence statements underwent a second round of expert panel voting, where consensus was achieved for all. For the diagnostic criteria, the final agreement rate, after the third vote, was 90.7%. Public stakeholder feedback was incorporated into the diagnostic criteria revision prior to the third expert panel vote. A terminology question was added to the third round of Delphi voting, where 30 of 32 (93.8%) expert panel members agreed that 'the diagnostic label 'concussion' may be used interchangeably with 'mild TBI' when neuroimaging is normal or not clinically indicated.' CONCLUSIONS: New diagnostic criteria for mild TBI were developed through an evidence review and expert consensus process. Having unified diagnostic criteria for mild TBI can improve the quality and consistency of mild TBI research and clinical care.

Examining the Association Between Adverse Childhood Experiences and Lifetime History of Head or Neck Injury and Concussion in Children From the United States.

OBJECTIVE: Our objective was to determine whether there is an association between adverse childhood experiences (ACEs) and lifetime history of early childhood mild head or neck injury and concussion in a nationally representative US cohort. SETTING AND DESIGN: This is a cross-sectional study using data from the Adolescent Brain Cognitive Development (ABCD) Study (data release 3.0), a prospective investigation of child brain development and health. PARTICIPANTS: There were 11 878 children aged 9 or 10 years at baseline, recruited from 21 school-based sites in the United States. After excluding children with missing questionnaires for the primary exposure variable and children with severe brain injuries involving more than 30-minute loss of consciousness, the final sample size was 11 230 children. MEASURES: The primary exposure variable was ACEs. We measured eight ACEs: sexual abuse, physical abuse, emotional neglect, parent domestic violence, parent substance use disorder, parental mental illness, parent criminal involvement, and parent divorce. The primary outcomes were head or neck injury and concussion, measured using the Ohio State University Traumatic Brain Injury Screen-Identification Method Short Form. RESULTS: The sample (N = 11 230) was 52% boys with a mean age of 9.9 years (SD = 0.62 years). The racial and ethnic makeup was reflective of national demographics. Having a higher overall ACE count was associated with higher odds of head or neck injury, with greater odds with more ACEs reported. Children with 2 ACEs had 24% greater odds of head or neck injury (AOR = 1.24, 95% confidence interval [CI] = 1.06-1.45) and 64% greater odds of concussion (AOR = 1.64, 95% CI = 1.18-2.22), and children with 4 or more ACEs had 70% greater odds of head or neck injury (AOR = 1.7, 95% CI = 1.14, 2.49) and 140% greater odds of concussion (AOR = 2.4, 95% CI = 1.15-4.47). The individual ACE categories of sexual abuse, parent domestic violence, parental mental illness, and parent criminal involvement were significantly associated with increased risk of head or neck injury and parental mental illness with increased risk of concussion. CONCLUSIONS AND RELEVANCE: ACEs are associated with early childhood mild head or neck injury and concussion and should be integrated in head injury prevention and intervention efforts.

Litigation, Performance Validity Testing, and Treatment Outcomes in Adults With Mild Traumatic Brain Injury.

OBJECTIVE: To investigate whether involvement in litigation and performance validity test (PVT) failure predict adherence to treatment and treatment outcomes in adults with persistent symptoms after mild traumatic brain injury (mTBI). SETTING: Outpatient concussion clinics in British Columbia, Canada. Participants were assessed at intake (average 12.9 weeks postinjury) and again following 3 to 4 months of rehabilitation. PARTICIPANTS: Adults who met the World Health Organization Neurotrauma Task Force definition of mTBI. Litigation status was known for 69 participants (n = 21 reported litigation), and 62 participants completed a PVT (n = 13 failed the Test of Memory Malingering) at clinic intake. DESIGN: Secondary analysis of a clinical trial (ClinicalTrials.gov #NCT03972579). MAIN MEASURES: Outcomes included number of completed sessions, homework adherence, symptoms (Rivermead Post Concussion Symptoms Questionnaire), disability ratings (World Health Organization Disability Assessment Schedule 2.0), and patient-rated global impression of change. RESULTS: We did not observe substantial differences in session and homework adherence associated with litigation or PVT failure. Disability and postconcussion symptoms generally improved with treatment. Involvement in litigation was associated with a smaller improvement in outcomes, particularly disability (B = 2.57, 95% confidence interval [CI] [0.25-4.89], P = .03) and patient-reported global impression of change (odds ratio [OR] = 4.19, 95% CI [1.40-12.57], P = .01). PVT failure was not associated with considerable differences in treatment outcomes. However, participants who failed the PVT had a higher rate of missing outcomes (31% vs 8%) and perceived somewhat less global improvement (OR = 3.47, 95% CI [0.86-14.04]; P = .08). CONCLUSION: Adults with mTBI who are in litigation or who failed PVTs tend to adhere to and improve following treatment. However, involvement in litigation may be associated with attenuated improvements, and pretreatment PVT failure may predict lower engagement in the treatment process.

Psychological Contributions to Symptom Provocation Testing After Concussion.

OBJECTIVE: Following concussion, symptoms such as headache, dizziness, and fatigue may transiently worsen or reemerge with increased exertion or activity. Standardized tests have been developed to assess symptom increases following aerobic, cognitive, or vestibular/oculomotor challenge. Although neurophysiological mechanisms are proposed to underlie symptom increases following exertion, psychological factors such as anxiety and misinterpretation of normal bodily sensations may also play a role. In this study, we examined the contribution of psychological factors to symptom provocation testing outcomes. SETTING: Two outpatient concussion clinics in British Columbia, Canada. PARTICIPANTS: Adults with persistent symptoms following concussion ( N = 79; 62% women). DESIGN: In a single session, participants completed self-report questionnaires measuring the psychological factors of interest and underwent symptom provocation testing including aerobic (Buffalo Concussion Bike Test; BCBT), cognitive (National Institutes of Health Toolbox-Cognition Battery; NIHTB-CB), and vestibular/oculomotor (Vestibular/Ocular Motor Screening for Concussion; VOMS) challenge. MAIN MEASURES: Psychological factors of interest included premorbid and current anxiety (Generalized Anxiety Disorder-7; GAD-7), catastrophizing (Pain Catastrophizing Scale-Adapted; PCS-A), fear avoidance behavior (Fear Avoidance Behavior after Traumatic Brain Injury; FAB-TBI), and somatization (Patient Health Questionnaire-15; PHQ-15). Our primary outcome variables were self-reported symptom change during each symptom provocation test. RESULTS: We found that current anxiety ( B = 0.034; 95% CI = 0.003, 0.065), symptom catastrophizing ( B = 0.013; 95% CI = 0.000, 0.026), fear avoidance behavior ( B = 0.029; 95% CI = 0.008, 0.050), and somatization ( B = 0.041; 95% CI = 0.007, 0.075) were associated with increased symptoms during the VOMS in univariate models adjusted for time postinjury but not in a multivariable model that included all covariates. The psychological variables of interest were not significantly related to symptom change during the BCBT or NIHTB-CB. CONCLUSION: Our findings suggest that symptom provocation test failure should be interpreted with caution because it might indicate psychological maladjustment rather than lingering brain injury or incomplete neurophysiological recovery.

Incidence of acute neurosurgery for traumatic brain injury in children-a nationwide analysis from 1998 to 2018.

BACKGROUND: Most of moderate and severe pTBIs are managed conservatively, but in some cases neurosurgical interventions are needed. The incidence rates of acute pTBI neurosurgery vary considerably between countries and operation types. Our goal was to assess the incidence of acute pTBI neurosurgery in Finland. METHODS: We conducted a retrospective Finnish register-based cohort study from 1998 to 2018. We included all patients that were 0 to 17 years of age at the time of the TBI. The incidence rates of patients with pTBI undergoing neurosurgery and the rates for specific operation types were calculated per 100,000 person-years. We compared the annual incidences with incidence rate ratios (IRR) with 95% confidence intervals (CI). We stratified patients to three age categories: (i) 0 to 3 years of age, (ii) 4 to 12 years of age, and (iii) 13 to 17 years of age. RESULTS: The total number of neurosurgeries for acute pTBI during the study period was 386, and the cumulative incidence was 1.67 operations per 100,000 person-years. The cumulative incidence during the 21-year follow-up was highest at the age of 16 (IRR 4.78, CI 3.68 to 6.11). Boys had a 2.42-time higher cumulative incidence (IRR 2.35, CI 1.27 to 3.99) than girls (IRR 0.97, CI 0.35 to 2.20). The most common neurosurgery was an evacuation of an intracranial hemorrhage (n = 171; 44.3%). CONCLUSION: The incidence of neurosurgeries for pTBIs has been stable from 1998 to 2018. The incidence was highest at the age of 16, and boys had higher incidence than girls.

What tests and measures accurately diagnose persisting post-concussive symptoms in children, adolescents and adults following sport-related concussion? A systematic review.

OBJECTIVE: To determine what tests and measures accurately diagnose persisting post-concussive symptoms (PPCS) in children, adolescents and adults following sport-related concussion (SRC). DESIGN: A systematic literature review. DATA SOURCES: MEDLINE, Embase, PsycINFO, Cochrane Central Register of Controlled Trials, CINAHL and SPORTDiscus through March 2022. ELIGIBILITY CRITERIA: Original, empirical, peer-reviewed findings (cohort studies, case-control studies, cross-sectional studies and case series) published in English and focused on SRC. Studies needed to compare individuals with PPCS to a comparison group or their own baseline prior to concussion, on tests or measures potentially affected by concussion or associated with PPCS. RESULTS: Of 3298 records screened, 26 articles were included in the qualitative synthesis, including 1016 participants with concussion and 531 in comparison groups; 7 studies involved adults, 8 involved children and adolescents and 11 spanned both age groups. No studies focused on diagnostic accuracy. Studies were heterogeneous in participant characteristics, definitions of concussion and PPCS, timing of assessment and the tests and measures examined. Some studies found differences between individuals with PPCS and comparison groups or their own pre-injury assessments, but definitive conclusions were not possible because most studies had small convenience samples, cross-sectional designs and were rated high risk of bias. CONCLUSION: The diagnosis of PPCS continues to rely on symptom report, preferably using standardised symptom rating scales. The existing research does not indicate that any other specific tool or measure has satisfactory accuracy for clinical diagnosis. Future research drawing on prospective, longitudinal cohort studies could help inform clinical practice.

Examining later-in-life health risks associated with sport-related concussion and repetitive head impacts: a systematic review of case-control and cohort studies.

OBJECTIVE: Concern exists about possible problems with later-in-life brain health, such as cognitive impairment, mental health problems and neurological diseases, in former athletes. We examined the future risk for adverse health effects associated with sport-related concussion, or exposure to repetitive head impacts, in former athletes. DESIGN: Systematic review. DATA SOURCES: Search of MEDLINE, Embase, Cochrane, CINAHL Plus and SPORTDiscus in October 2019 and updated in March 2022. ELIGIBILITY CRITERIA: Studies measuring future risk (cohort studies) or approximating that risk (case-control studies). RESULTS: Ten studies of former amateur athletes and 18 studies of former professional athletes were included. No postmortem neuropathology studies or neuroimaging studies met criteria for inclusion. Depression was examined in five studies in former amateur athletes, none identifying an increased risk. Nine studies examined suicidality or suicide as a manner of death, and none found an association with increased risk. Some studies comparing professional athletes with the general population reported associations between sports participation and dementia or amyotrophic lateral sclerosis (ALS) as a cause of death. Most did not control for potential confounding factors (eg, genetic, demographic, health-related or environmental), were ecological in design and had high risk of bias. CONCLUSION: Evidence does not support an increased risk of mental health or neurological diseases in former amateur athletes with exposure to repetitive head impacts. Some studies in former professional athletes suggest an increased risk of neurological disorders such as ALS and dementia; these findings need to be confirmed in higher quality studies with better control of confounding factors. PROSPERO REGISTRATION NUMBER: CRD42022159486.

Amsterdam 2022 process: A summary of the methodology for the Amsterdam International Consensus on Concussion in Sport.

The purpose of this paper is to summarise the consensus methodology that was used to inform the International Consensus Statement on Concussion in Sport (Amsterdam 2022). Building on a Delphi process to inform the questions and outcomes from the 5th International Conference on Concussion in Sport, the Scientific Committee identified key questions, the answers to which would help encapsulate the current science in sport-related concussion and help guide clinical practice. Over 3½ years, delayed by 2 years due to the pandemic, author groups conducted systematic reviews on each selected topic. The 6th International Conference on Concussion in Sport was held in Amsterdam (27-30 October 2022) and consisted of 2 days of systematic review presentations, panel discussions, question and answer engagement with the 600 attendees, and abstract presentations. This was followed by a closed third day of consensus deliberations by an expert panel of 29 with observers in attendance. The fourth day, also closed, was dedicated to a workshop to discuss and refine the sports concussion tools (Concussion Recognition Tool 6 (CRT6), Sport Concussion Assessment Tool 6 (SCAT6), Child SCAT6, Sport Concussion Office Assessment Tool 6 (SCOAT6) and Child SCOAT6). We include a summary of recommendations for methodological improvements for future research that grew out of the systematic reviews.

Consensus statement on concussion in sport: the 6th International Conference on Concussion in Sport-Amsterdam, October 2022.

For over two decades, the Concussion in Sport Group has held meetings and developed five international statements on concussion in sport. This 6th statement summarises the processes and outcomes of the 6th International Conference on Concussion in Sport held in Amsterdam on 27-30 October 2022 and should be read in conjunction with the (1) methodology paper that outlines the consensus process in detail and (2) 10 systematic reviews that informed the conference outcomes. Over 3½ years, author groups conducted systematic reviews of predetermined priority topics relevant to concussion in sport. The format of the conference, expert panel meetings and workshops to revise or develop new clinical assessment tools, as described in the methodology paper, evolved from previous consensus meetings with several new components. Apart from this consensus statement, the conference process yielded revised tools including the Concussion Recognition Tool-6 (CRT6) and Sport Concussion Assessment Tool-6 (SCAT6, Child SCAT6), as well as a new tool, the Sport Concussion Office Assessment Tool-6 (SCOAT6, Child SCOAT6). This consensus process also integrated new features including a focus on the para athlete, the athlete's perspective, concussion-specific medical ethics and matters related to both athlete retirement and the potential long-term effects of SRC, including neurodegenerative disease. This statement summarises evidence-informed principles of concussion prevention, assessment and management, and emphasises those areas requiring more research.

Neurocognitive functioning and symptoms across levels of collision and contact in male high school athletes.

OBJECTIVE: We sought to determine whether male collision sport athletes perform worse on computerised neurocognitive assessments and report higher symptom burdens than athletes in contact (but not collision) sports and athletes in non-contact sports. METHODS: This cross-sectional study used data collected by the Massachusetts Concussion Management Coalition on high school boys who underwent computerised neurocognitive testing between 2009 and 2018. We divided sports participation in three different sport types: (1) collision, (2) contact, non-collision and (3) non-contact. Our outcomes included the four computerised neurocognitive composite scores (verbal memory, visual memory, visual motor speed and reaction time) and the total symptom score. The independent variable was sport type (collision, contact, non-contact), adjusted for age, concussion history and comorbidities. RESULTS: Of the 92 979 athletes (age: 15.59±2.08 years) included in our study, collision sport athletes performed minimally but significantly worse than other athletes on neurocognitive composite scores (verbal memory: ß=-1.64, 95% CI -1.85 to -1.44; visual memory: ß=-1.87, 95% CI -2.14 to -1.60; visual motor speed: ß=-2.12, 95% CI -2.26 to -1.97; reaction time: ß=0.02, 95% CI 0.02 to 0.02). Collision and contact sport athletes also had slightly but significantly lower total symptom scores (collision: 3.99±7.17; contact: 3.78±6.81; non-contact: 4.32±7.51, p<0.001, η2=0.001) than non-contact sport athletes. CONCLUSION: There are minimal observed differences in performance on neurocognitive assessments between collision sport, contact sport and non-contact sport athletes. The repetitive subconcussive head impacts associated with collision sport participation do not appear to negatively affect self-reported symptoms or neurocognitive functioning in current youth athletes.

Interpreting change on the Symbol Digit Modalities Test in people with relapsing multiple sclerosis using the reliable change methodology.

BACKGROUND: The Symbol Digit Modalities Test (SDMT) is increasingly utilized in clinical trials. A SDMT score change of 4 points is considered clinically important, based on association with employment anchors. Optimal thresholds for statistically reliable SDMT changes, accounting for test reliability and measurement error, are yet to be applied to individual cases. OBJECTIVE: The aim of this study was to derive a statistically reliable marker of individual change on the SDMT. METHODS: This prospective, case-control study enrolled 166 patients with multiple sclerosis (MS). SDMT scores at baseline, relapse, and 3-month follow-up were compared between relapsing and stable patient groups. Using data from the stable group and three previously published studies, candidate thresholds for reliable decline were calculated and validated against other tests and a clinically meaningful anchor-cognitive relapse. RESULTS: Candidate thresholds for reliable decline at the 80% confidence level varied between 6 and 11 points. An SDMT change of 8 or more raw score points was deemed to offer the best balance of discriminatory power and external validity for estimating cognitive decline. CONCLUSION: This study illustrates the feasibility and usefulness of reliable change methodology for identifying statistically meaningful cognitive decline that could be implemented to identify change in individual patients, for both clinical management and clinical trial outcomes.

Trajectories of Persistent Postconcussion Symptoms and Factors Associated With Symptom Reporting After Mild Traumatic Brain Injury.

OBJECTIVE: To examine the trajectories of persistent postconcussion symptoms (PPCS) after mild traumatic brain injury (MTBI) and to investigate which injury-related and personal factors are associated with symptom reporting. DESIGN: Prospective longitudinal cohort study. Follow-up at 3 and 12 months postinjury. SETTING: A level 1 trauma center and an emergency outpatient clinic. PARTICIPANTS: Patients with MTBI (n=358), trauma controls (n=75), and community controls (n=78). MAIN OUTCOME MEASURES: Symptoms were assessed with the British Columbia Postconcussion Symptom Inventory (BC-PSI). Participants were categorized as having moderate to severe PPCS (msPPCS) when reporting ≥3 moderate/severe symptoms or a BC-PSI total score of ≥13. BC-PSI total scores were compared between the groups and were further used to create cutoffs for reliable change by identifying uncommon and very uncommon change in symptoms in the community control group. Associations between symptom reporting and 25 injury-related and personal factors were examined. RESULTS: The MTBI group had a similar prevalence of msPPCS at 3 and 12 months (21%) and reported more symptoms than the control groups. Analyses of individual trajectories, however, revealed considerable change in both msPPCS and BC-PSI total scores in the MTBI group, where both worsening and improvement was common. Intracranial lesions on computed tomography were associated with a greater likelihood of improving from 3 to 12 months. Those with msPPCS at both assessments were more likely to be women and to have these personal preinjury factors: reduced employment, pain, poor sleep, low resilience, high neuroticism and pessimism, and a psychiatric history. CONCLUSIONS: Group analyses suggest a stable prevalence of msPPCS the first year postinjury. However, there was considerable intraindividual change. Several personal factors were associated with maintaining symptoms throughout the first year.

Feasibility of Concussion Rehabilitation Approaches Tailored to Psychological Coping Styles: A Randomized Controlled Trial.

OBJECTIVE: To evaluate the feasibility of a clinical trial involving participants with concussion randomized to treatments designed to address fear avoidance or endurance coping, which are risk factors for disability. A secondary objective was to evaluate whether each treatment could affect selective change on targeted coping outcomes. DESIGN: Randomized controlled trial. SETTING: Outpatient concussion clinics. PARTICIPANTS: Adults (N=73, mean age=42.5y) who had persistent postconcussion symptoms and high avoidance or endurance behavior were enrolled at a mean of 12.9 weeks post injury. Ten participants did not complete treatment. INTERVENTIONS: Participants were randomized to an interdisciplinary rehabilitation program delivered via videoconferencing and tailored to avoidance coping (graded exposure therapy [GET]) or endurance coping (operant condition-based pacing strategies plus mindfulness training [Pacing+]). MAIN OUTCOME MEASURES: Feasibility outcomes included screening efficiency, accrual, credibility, treatment fidelity, adherence, and retention. Avoidance was measured with the Fear Avoidance Behavior after Traumatic Brain Injury Questionnaire and endurance behavior with the Behavioral Response to Illness Questionnaire. RESULTS: Screening efficiency, or the proportion of clinic patients who were assessed for eligibility, was 44.5% (275 of 618). A total of 65.8% (73 of 111) of eligible patients were randomized (37 to GET, 36 to Pacing+), meeting accrual targets; 91.7% (55 of 60) of participants perceived treatment as credible. Therapists covered a mean of 96.8% of essential prescribed elements, indicating excellent fidelity. The majority (71.2%; 47 of 66) of participants consistently attended treatment sessions and completed between-session homework. Retention was strong, with 65 of 73 (89%) randomized participants completing the outcome assessment. GET was associated with greater posttreatment reductions in avoidance behavior compared with Pacing+ (Cohen's drepeated measures, 0.81), whereas the treatment approach-specific effect of Pacing+ on endurance behavior was less pronounced (Cohen's drepeated measures, 0.39). CONCLUSIONS: These findings support a future efficacy-focused clinical trial. GET has the potential to selectively reduce fear avoidance behavior after concussion, and, via this mechanism, to prevent or reduce disability.

Incidence of surgically treated post-traumatic hydrocephalus 6 months following head injury in patients undergoing acute head computed tomography.

BACKGROUND: Post-traumatic hydrocephalus (PTH) is a well-known complication of head injury. The percentage of patients experiencing PTH in trauma cohorts (0.7-51.4%) varies greatly in the prior literature depending on the study population and applied diagnostic criteria. The objective was to determine the incidence of surgically treated PTH in a consecutive series of patients undergoing acute head computed tomography (CT) following injury. METHODS: All patients (N = 2908) with head injuries who underwent head CT and were treated at the Tampere University Hospital's Emergency Department (August 2010-July 2012) were retrospectively evaluated from patient medical records. This study focused on adults (18 years or older) who were residents of the Pirkanmaa region at the time of injury and were clinically evaluated and scanned with head CT at the Tampere University Hospital's emergency department within 48 h after injury (n = 1941). A thorough review of records for neurological signs and symptoms of hydrocephalus was conducted for all patients having a radiological suspicion of hydrocephalus. The diagnosis of PTH was based on clinical and radiological signs of the condition within 6 months following injury. The main outcome was surgical treatment for PTH. Clinical evidence of shunt responsiveness was required to confirm the diagnosis of PTH. RESULTS: The incidence of surgically treated PTH was 0.15% (n = 3). Incidence was 0.08% among patients with mild traumatic brain injury (TBI) and 1.1% among those with moderate to severe TBI. All the patients who developed PTH underwent neurosurgery during the initial hospitalization due to the head injury. The incidence of PTH among patients who underwent neurosurgery for acute traumatic intracranial lesions was 2.7%. CONCLUSION: The overall incidence of surgically treated PTH was extremely low (0.15%) in our cohort. Analyses of risk factors and the evaluation of temporal profiles could not be undertaken due to the extremely small number of cases.

Craniotomies following acute traumatic brain injury in Finland-a national study between 1997 and 2018.

BACKGROUND: A number of patients who sustain a traumatic brain injury (TBI) require surgical intervention due to acute intracranial bleeding. The aim of this retrospective study was to assess the national trends of acute craniotomies following TBI in the Finnish adult population. METHODS: The data were collected retrospectively from the Finnish Care Register for Health Care (1997-2018). The study cohort covered all first-time registered craniotomies following TBI in patients aged 18 years or older. A total of 7627 patients (median age = 59 years, men = 72%) were identified. RESULTS: The total annual incidence of acute trauma craniotomies decreased by 33%, from 8.6/100,000 in 1997 to 5.7/100,000 in 2018. The decrease was seen in both genders and all age groups, as well as all operation subgroups (subdural hematoma, SDH; epidural hematoma, EDH; intracerebral hematoma, ICH). The greatest incidence rate of 15.4/100,000 was found in patients 70 years or older requiring an acute trauma craniotomy. The majority of surgeries were due to an acute SDH and the patients were more often men. The difference between genders decreased with age (18-39 years = 84% men, 40-69 = 78% men, 70 + years = 55% men). The median age of the patients increased from 58 to 65 years during the 22-year study period. CONCLUSIONS: The number of trauma craniotomies is gradually decreasing; nonetheless, the incidence of TBI-related craniotomies remains high among geriatric patients. Further studies are needed to determine the indications and derive evidence-based guidelines for the neurosurgical care of older adults with TBIs to meet the challenges of the growing elderly population.