Immediate Post-Concussion Assessment And Cognitive Testing Research Articles

Does time since concussion alter the factor structure of a multidomain assessment in adolescents?

ABSTRACT The utilization of principal component analysis (PCA) approaches to concussion is beneficial to inform the interpretation of clinical outcome data in adolescent patients. While researchers have identified factors using post-concussive symptom scales and cognitive testing, there has yet to be a PCA that incorporates vestibular or oculomotor outcomes, or that focuses exclusively on adolescents. Moreover, the role of time since injury has not been examined in relation to concussion factors in this at-risk population. PCA methods were applied to two independent samples of 237 adolescents who presented to an outpatient concussion clinic: 1) ≤7 days (n = 145), and 2) 8 days-1 month (n = 92). The two separate PCAs included nine clinical assessments comprised of: a) four symptoms factors (cognitive/fatigue/migraine, affective, somatic, sleep), b) memory and speeded cognitive performance, c) near point of convergence (NPC), d) oculomotor, and e) vestibular outcomes. A three-component model including 1) symptoms, 2) cognitive, and 3) vestibular/oculomotor factors that accounted for 69.2% of the variance was supported for the ≤7 days sample. All items except somatic symptoms loaded. A different three-component model was supported for the 8 days-1 month sample, including 1) vestibulo-ocular migraine, 2) visuo-cognitive, and 3) affective-sleep that accounted for 72.1% of the variance, with all items loading. The findings supported two different concussion factor models that highlight the influence of time since injury and importance of considering vestibular and oculomotor outcomes in adolescents. Clinicians should evaluate these different factors using a comprehensive, multi domain approach to better inform assessment and monitor recovery in adolescent patients following concussion. Abbreviations: Principal Components Analysis (PCA), Immediate Post-concussion Assessment and Cognitive Testing (ImPACT), Post-concussion Symptom Scale (PCSS), Vestibular/Ocular Motor Screening (VOMS)

The Current Status of Concussion Assessment Scales: A Critical Analysis Review.

Concussion is a complex pathophysiologic process that affects the brain; it is induced by biomechanical forces, with alteration in mental status with or without loss of consciousness. Concussion assessment tools may be broadly categorized into (1) screening tests such as the SAC (Standardized Assessment of Concussion), the BESS (Balance Error Scoring System), and the King-Devick (KD) test; (2) confirmatory tests including the SCAT (Sport Concussion Assessment Tool), the ImPACT (Immediate Post-Concussion Assessment and Cognitive Testing), and the VOMS (Vestibular Oculomotor Screening); and (3) objective examinations such as brain network activation (BNA) analysis, imaging studies, and physiologic markers. The KD, child SCAT3 (cSCAT3), child ImPACT (cImPACT), and VOMS tests may be used to evaluate for concussion in the pediatric athlete. Future work with BNA, functional magnetic resonance imaging, diffusion tensor imaging, and serum biomarkers may provide more objective assessment of concussion, neurologic injury, and subsequent recovery.

A - 29 Language Differences in Neurocognitive Scores and Symptom Report in Professional Football Players

Abstract Objective The purpose of this study was to investigate the role of language on neurocognitive test outcomes and concussion symptom ratings in professional football players. Methods Design/Setting - A retrospective cross-section analysis of 1546 male Canadian Football League (CFL) athletes was conducted using baseline data collected from the Immediate Post-Concussion Assessment and Cognitive Test (ImPACT) across the 2016–18 competitive seasons. Independent Variables - Participants (1546) were divided into three language categories, native English-speaking, bilingual – whose first language was English, and English as a second language (ESL). Years of education, age, and concussion history were entered as co-variates. Outcome Measure -The 5 Composite scores from ImPACT and the 22 symptoms from the post-concussion symptom scale (PCSS). Results Results of the MANCOVA showed no significant differences between language groups on any of the five ImPACT composite scores F(10, 3072) = 1.09, p = 0.36. The Kruskall-Wallis test revealed significant differences were found in three symptoms including dizziness [X2(2, 1486) = 32.85, p < 0.001)], sadness [X2(2, 1486) = 6.505, p = 0.04], and concentration [X2(2, 1486) = 11.01, p = 0.004)] with the bilingual and non-native English speakers having higher scores. Conclusions This study suggests that cultural and linguistic differences should be considered when administering CNTs. While differences in cognitive outcomes have not been consistently found across studies, differences in baseline symptom reports have been consistently demonstrated. Information pertaining to a patient’s level of acculturation and language proficiency is important for examiners when working with diverse populations. Continuing to develop language-specific normative databases is encouraged.

A - 11 Are Self-Reported Cognitive Symptoms an Accurate Evaluation of Cognitive Functioning?

Abstract Objective The purpose of this study was to evaluate whether self-reports of cognitive symptoms were associated with cognitive test performances. Methods The sample included 112 Canadian Football League (CFL) athletes who were diagnosed using CFL concussion protocols. All participants underwent a cognitive assessment at baseline and prior to medical clearance. The battery included the immediate post-concussion assessment and cognitive testing (ImPACT) and The Post-Concussion Symptom Checklist. Results Self-reported cognitive symptoms and cognitive test performances were evaluated using Spearman’s rank correlations (rho; ρ). There were significant negative correlations between post-concussion verbal memory composite and the self-reported cognitive symptoms total (ρ = −0.22). Similar patterns were found for visual memory composite and the self-reported cognitive symptom total (ρ = −0.19). Paired-samples t-tests were used to assess differences between pre- and post-concussion scores. Cases were omitted if there were no pre- or post-test. If multiple concussions were sustained, the first assessment was used (n = 99). There was a significant difference between the pre- and post-test results between the subjective cognitive symptom total (t = −2.034, p > 0.05). Conclusions These outcomes suggest that CFL athletes report significantly higher cognitive symptoms following a concussion. Additionally, the pre-test subjective measures were not correlated to objective cognitive functioning. However, post-concussion subjective measures were negatively correlated with verbal and visual memory. This suggests that self-reports were more accurate at assessing their overall functioning following a concussion.

A - 27 The Clinical Utilization of SWAY and mBESS for Post-Trauma and Follow-up Concussion Evaluations

Abstract Objective SWAY is a mobile software system using an accelerometer designed to measure postural sway and reaction time in the context of concussion. This study examined the efficacy of SWAY in detecting changes in balance and reaction time before and after concussion. Methods College athletes (N = 30, 10 females) underwent baseline, post-trauma, and follow-up evaluations following a concussion including SWAY, mBESS, Sports Concussion Assessment Tool 5th Edition (SCAT-5), and Immediate Post Concussion Assessment and Cognitive Testing (ImPACT). Results Paired-samples t-tests revealed a decline in SWAY balance from baseline (M = 82.65, SD = 14.48) to post-trauma (M = 74.61, SD = 17.41), t(29) = 2.99, p = 0.006, but no significant difference was observed in reaction time (M = 5.07, SD = 13.61), t(29) = 2.04, p = 0.050. Meanwhile, balance improved at follow-up (M = 78.93, SD = 15.32), and was no longer discrepant from baseline (M = 81.97, SD = 14.51), t(21) = 1.03, p = 0.316. Similarly, there was a significant decline in mBESS scores from baseline (M = 2.88, SD = 3.62) to post-trauma (M = 5.68, SD = 5.32), t(24) = −3.51, p = 0.002, followed by a return to baseline at follow up (M = 4.22, SD = 4.95), t(22) = −1.60, p = 0.124. Conclusions Although challenges were apparent in obtaining an optimal baseline, current results appear to support the clinical utility of SWAY for assessing balance in the context of concussion evaluations. Further research appears warranted to support SWAY as a method of diagnosing concussion and monitoring return to baseline.

Understanding racial differences in computerized neurocognitive test performance and symptom-reporting to deliver culturally competent patient-centered care for sport-related concussion

Objective This study examined neurocognitive performance and symptoms between concussed Black and White collegiate athletes at baseline, post-injury, and change from baseline to post-injury. Method The Immediate Post-Concussion Assessment and Cognitive Test (ImPACT) was used to measure neurocognitive performance and four concussion symptom clusters for 235 concussed collegiate athletes. Between-groups differences were documented at baseline and post-injury, along with change in scores for sex/race, and sport/race groups, using ANOVAs. Baseline scores, and days-to-post-test were covariates in post-injury comparisons. Symptom endorsement by race was evaluated using chi-square analyses. Results At baseline, group comparisons by race and sex showed that Black male/female athletes scored lower on reaction time (RT; p = .008), White females scored higher on verbal memory (VerbMem; p = .001), Black females scored lower on visual motor processing speed (VMS; p = .001), and Black football athletes scored slower/poorer on RT (p = .001) and VMS (p = .006). Post-injury, Black males scored lower on visual memory (VisMem; p = .005) and VMS (p = .002), and Black football athletes scored slower on VMS (p = .005), whereas White non-football athletes scored higher on VerbMem (p = .002) and reported fewer symptoms. Significant time-by-sport/race interactions were found for VerbMem (p < .001), VisMem (p < .001) and reported symptoms. With respect to post-injury symptom scores/endorsement, Black athletes scored significantly higher for physical (p = .01) and sleep (p = .01) symptoms. Conclusion These findings drive the conversation of how subjective measures of symptoms, and objective clinical concussion measures, may relate to the concussion recovery process and providing a culturally competent clinical management approach for diverse patients.

Sleep Insufficiency and Baseline Preseason Concussion-Like Symptom Reporting in Youth Athletes.

To examine the association between insufficient sleep and baseline symptom reporting in healthy student athletes. Cross-sectional cohort study. Preseason testing for student athletes. Student athletes (n = 19 529) aged 13 to 19 years who completed the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT), including the number of hours slept the night before, and denied having developmental/health conditions, a concussion in the past 6 months, and a previous history of 2 or more concussions. Total hours of sleep the night before testing (grouped by ≤5, 5.5-6.5, 7-8.5, and ≥9 hours), gender, and concussion history. Symptom burden on the Post-Concussion Symptom Scale (modified to exclude sleep-related items), cognitive composite scores, and prevalence of athletes who reported a symptom burden resembling the International Classification of Diseases, 10th Revision (ICD-10) diagnosis of postconcussional syndrome (PCS). Fewer hours of sleep, gender (ie, girls), and 1 previous concussion (vs 0) were each significantly associated with higher total symptom scores in a multivariable model (F = 142.01, P < 0.001, R2 = 0.04). When a gender-by-sleep interaction term was included, the relationship between sleep and symptoms was stronger for girls compared with boys. In healthy athletes who slept ≤5 hours, 46% of girls and 31% of boys met the criteria for ICD-10 PCS compared with 16% of girls and 11% of boys who slept ≥9 hours. Sleep duration was not meaningfully associated with neurocognitive performance. Insufficient sleep the night before testing is an important factor to consider when interpreting symptom reporting, especially for girls. It will be helpful for clinicians to take this into account when interpreting both baseline and postinjury symptom reporting.

Sport Contact Level Affects Post-Concussion Neurocognitive Performance in Young Athletes.

Contact level affects the incidence of sports-related concussion. However, the effects of contact level on injury severity and recovery are less clear and are the focus of this study. Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) for athletes aged 12-22 was performed at baseline (n=10,907 for 7,058 athletes), after suspected concussion determined by physicians or athletic trainers (n=5,062 for 4,419 athletes), and during follow-up visits (n=3,264 for 2,098 athletes). Athletes played contact/collision (CC), limited contact (LC), and noncontact (NC) sports. Injury incidence, severity, and recovery were measured using raw and change from baseline neurocognitive test scores. Comparisons between groups used univariate analysis and multivariable regression controlling for demographic variables. Compared to CC athletes, LC and NC athletes showed decreased suspected concussion incidence. At initial post-injury testing, all neurocognitive test scores were similar between groups except changes from baseline for processing speed were improved for LC compared to CC athletes. Upon follow-up testing, raw neurocognitive scores were better for NC compared to the contact collision athletes in verbal memory, processing speed, total symptom score, migraine cluster, cognitive cluster, and neuropsychiatric cluster scores. For change from baseline scores, LC athletes exhibited better performance on verbal memory, processing speed, and reaction time but also showed higher neuropsychiatric scores than CC athletes. Neurocognitive scores between contact levels were similar at the first post-injury test. However, follow up showed many improved scores and symptoms for limited and NC sports compared to CC sports, which may indicate faster recovery.

Using Oculomotor Features to Predict Changes in Optic Nerve Sheath Diameter and ImPACT Scores From Contact-Sport Athletes.

There is mounting evidence linking the cumulative effects of repetitive head impacts to neuro-degenerative conditions. Robust clinical assessment tools to identify mild traumatic brain injuries are needed to assist with timely diagnosis for return-to-field decisions and appropriately guide rehabilitation. The focus of the present study is to investigate the potential for oculomotor features to complement existing diagnostic tools, such as measurements of Optic Nerve Sheath Diameter (ONSD) and Immediate Post-concussion Assessment and Cognitive Testing (ImPACT). Thirty-one high school American football and soccer athletes were tracked through the course of a sports season. Given the high risk of repetitive head impacts associated with both soccer and football, our hypotheses were that (1) ONSD and ImPACT scores would worsen through the season and (2) oculomotor features would effectively capture both neurophysiological changes reflected by ONSD and neuro-functional status assessed via ImPACT. Oculomotor features were used as input to Linear Mixed-Effects Regression models to predict ONSD and ImPACT scores as outcomes. Prediction accuracy was evaluated to identify explicit relationships between eye movements, ONSD, and ImPACT scores. Significant Pearson correlations were observed between predicted and actual outcomes for ONSD (Raw = 0.70; Normalized = 0.45) and for ImPACT (Raw = 0.86; Normalized = 0.71), demonstrating the capability of oculomotor features to capture neurological changes detected by both ONSD and ImPACT. The most predictive features were found to relate to motor control and visual-motor processing. In future work, oculomotor models, linking neural structures to oculomotor function, can be built to gain extended mechanistic insights into neurophysiological changes observed through seasons of participation in contact sports.

87842 The Effects of Head Impact Exposure on Changes in Neurocognitive and Oculomotor Function Across a High School American Football Season: A Pilot Study

ABSTRACT IMPACT: This work reveals the influence of a season of American football-related head impact exposure on two functional outcome measures in a cohort of adolescent boys, shedding light on the chronic effects of 'subconcussive head impacts.' OBJECTIVES/GOALS: To examine the influence of a season of exposure to head impacts in American football on changes in neurocognitive and oculomotor function in adolescent male athletes. METHODS/STUDY POPULATION: Participants were recruited from a local high school: the football group (FB; n = 26) was instrumented with sensor-installed mouthguards to track impact exposure during games and practices, and members of the men’s cross-country team were recruited to the control group (CON; n = 9). All participants were administered Immediate Post-concussion Assessment and Cognitive Testing (ImPACT) and were assessed for near point of convergence (NPC) at pre- and post-season. Linear models will be fit for changes in the five ImPACT composite scores and NPC values, with group and one of the head impact variables as predictors for each model. In a secondary within-group analysis, correlation coefficients will be calculated for the relationships between the head impact variables and the functional change scores for the FB group. RESULTS/ANTICIPATED RESULTS: The two groups did not differ significantly on age or number of previous concussions; the CON group had significantly lower BMI. Group assignment was significantly associated with change in NPC (p &lt; 0.05 for all three models); no significant associations were observed for any of the head impact variables with change in NPC. Group and each of the head impact variables (total impacts, sum of peak linear acceleration [PLA], and sum of peak rotational acceleration [PRA]) were not significantly associated with change in any of the five ImPACT composite scores. Change in visual memory composite score was negatively correlated with total impacts (r = -0.37, p = 0.034) and sum of PRA (r = -0.36, p = 0.040). DISCUSSION/SIGNIFICANCE OF FINDINGS: Significant, albeit relatively weak, correlations between change in visual memory composite score and two head impact kinematic variables, coupled with significant increases in NPC in the FB group compared to the CON group, suggest that a season of exposure to football-related head impacts has the potential to elicit minor functional impairments.

Influence of Autism and Other Neurodevelopmental Disorders on Cognitive and Symptom Profiles: Considerations for Baseline Sport Concussion Assessment.

The presence of neurodevelopmental disorders (ND) such as attention-deficit/hyperactivity disorder (ADHD) and learning disorders (LD) have demonstrated effects on Immediate Post-concussion Assessment and Cognitive Testing (ImPACT) performance. No current research has directly examined whether autism spectrum disorder (ASD) has similar effects. The current study compared ImPACT cognitive and symptom profiles in athletes with self-reported ASD to other NDs and healthy controls using case-control matching. The current study compared ImPACT baselines of high school athletes with ASD to athletes with other NDs (ADHD, LD, and co-occurring ADHD/LD) and healthy controls on cognitive composites and symptom reporting. Participants included 435 athletes (87 controls, 87 with ASD, 87 with ADHD, 87 with LD, and 87 with ADHD/LD) selected from a larger naturalistic sample. Athletes were matched to the ASD group based on age, sex, and sport using randomized case-matched selection from the larger database. Results revealed that athletes with ASD performed more poorly than healthy controls on the Visual Motor Speed composite. No differences were found for Post-concussion Symptom Scale (PCSS) domain scores. Differences in cognitive and symptom profiles among the athletes with other NDs were also found. Results elucidate patterns of baseline performance for athletes with ASD, demonstrating that there may not be significant differences between ASD and healthy controls on four of the five ImPACT composites, and no symptom reporting differences. Cognitive and symptom differences found for other NDs should be considered when interpreting baseline performance and for making return-to-play decisions in the absence of baseline assessment.

Effects of Recurrent Mild Traumatic Brain Injuries on Incidence, Severity, and Recovery of Concussion in Young Student-Athletes.

To examine the effects of recurrent concussions on the incidence, severity, and recovery of significant neurocognitive dysfunction (SND) in young athletes. Various US youth sports organizations that utilize Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) for baseline and postinjury concussion testing. Data from 11 563 ImPACT baseline evaluations of US student-athletes aged 12 to 22 years were separated into 2 cohorts: subjects reporting 2 or more previous concussions (PC; n = 976 baseline evaluations) at baseline and a control group reporting zero previous concussions (CT; n = 7743 baseline evaluations). Subjects reporting 1 prior concussion were excluded. Retrospective cohort. Differences in SND incidence, severity, and recovery between the 2 cohorts were assessed using chi-squared tests, t tests, survival analyses, and multivariate regressions. The PC cohort had a higher incidence of head injury leading to ImPACT (436.7 per 1000 person-years vs 194.4 per 1000 person-years, P < .0001) and a higher incidence of SND (140.4 vs 71.8, P < .0001) than controls. However, the Severity Index (SI) demonstrated that SND severity was lower in the PC group (7.55 vs 8.59, P = .04). Adjusted analyses similarly demonstrated that the PC cohort had increased SND incidence (odds ratio = 1.93; 95% CI, 1.61 to 2.31; P < .0001), decreased SI (β = -1.37; 95% CI, -2.40 to -0.34; P = .009), and equivalent recovery (hazard ratio = 0.98; 95% CI, 0.76 to 1.72; P = .90). Participants with a history of concussion have a higher incidence of SND but present with lower severity SND, which may be a result of increased concussion education or symptom awareness. Recurrent concussion has no significant impact on acute neurocognitive recovery. Together, these results provide evidence against the supposition that a history of concussion increases the severity of future SND.

Prolonged concussion effects: Constellations of cognitive deficits detected up to year after injury

Concussions are associated with an array of physical, emotional, cognitive, and sleep symptoms at multiple timescales. Cognitive recovery occurs relatively quickly – five-to-seven days on average. Yet, recent evidence suggests that some neurophysiological changes can be identified one year after a concussion. To that end, we examine more nuanced patterns in cognitive tests to determine whether cognitive abilities could identify a concussion within one-year post injury. A radial-basis (non-linear boundary) support vector machine classifier was trained to use cognitive performance measures to distinguish participants with no prior concussion from participants with prior concussion in the past year. After incorporating only 10 cognitive measures, or all 5 composite measures from the neurocognitive assessment (Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT)), over 90% accuracy was achieved in identifying both participants without prior concussions and participants with concussions in the past year, particularly when relying on non-linear patterns. Notably, classification accuracy stayed relatively constant between participants who had a concussion early or late in the one-year window. Thus, with substantial accuracy, a prior concussion can be identified using a non-linear combination of cognitive measures. Cognitive effects from concussion linger one-year post-injury, indicating the importance of continuing to follow concussion patients for many months after recovery and to take special note of constellations of cognitive abilities.

The Effects of On-Field Heat Index and Altitude on Concussion Assessments and Recovery Among NCAA Athletes.

Recent literature has indicated altitude may be a protective factor for concussion but it is unknown whether altitude or heat index affects recovery. To examine whether on-field heat index and altitude at the time of injury alter acute (< 48h) concussion assessments, days-to-asymptomatic, and days-to-return-to-play in collegiate athletes following concussion. Collegiate athletes (n = 187; age = 19.7 ± 1.4years; male = 70.6%) underwent baseline assessments across 30 universities and experienced a concussion in this retrospective cohort study. Altitude (m) and heat index (°C) at the time and location of injury were determined using valid online database tools. Acute concussion assessments included the Sport Concussion Assessment Tool (SCAT) symptom inventory, Balance Error Scoring System (BESS), and the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT). We used multiple linear regression models to determine whether heat index and altitude predicted each acute assessment outcome, days-to-asymptomatic, and days-to-return-to-play. Collegiate athletes were concussed at a 181.1m (range -0.6 to 2201.9m) median altitude and 17.8°C (range -6.1 to 35.6°C) median heat index. Altitude did not predict (p ≥ 0.265) any outcomes. Every one-degree increase in heat index reduced days-to-asymptomatic (p = 0.047; R2 = 0.06) and days-to-return-to-play (p = 0.006; R2 = 0.09) by 0.05 and 0.14days, respectively. Heat index and altitude did not explain significant variance in SCAT, BESS, and ImPACT composite scores (p's = 0.20-0.922). Our findings suggest that on-field altitude and heat index at the time of injury do not contribute to clinically meaningful changes on acute assessments or concussion recovery. On-field altitude and heat index do not appear to significantly alter assessment outcomes or clinical recovery, suggesting that environmental factors at altitudes below < 2500m are negligible outcomes for researchers and clinicians to consider post-concussion.

Influence of Special Education, ADHD, Autism, and Learning Disorders on ImPACT Validity Scores in High School Athletes

AbstractObjective:The Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) is commonly used to assist with post-concussion return-to-play decisions for athletes. Additional investigation is needed to determine whether embedded indicators used to determine the validity of scores are influenced by the presence of neurodevelopmental disorders (NDs).Method:This study examined standard and novel ImPACT validity indicators in a large sample of high school athletes (n = 33,772) with or without self-reported ND.Results:Overall, 7.1% of athletes’ baselines were judged invalid based on standard ImPACT validity criteria. When analyzed by group (healthy, ND), there were significantly more invalid ImPACT baselines for athletes with an ND diagnosis or special education history (between 9.7% and 54.3% for standard and novel embedded validity criteria) when compared to athletes without NDs. ND history was a significant predictor of invalid baseline performance above and beyond other demographic characteristics (i.e., age, sex, and sport), although it accounted for only a small percentage of variance. Multivariate base rates are presented stratified for age, sex, and ND.Conclusions:These data provide evidence of higher than normal rates of invalid baselines in athletes who report ND (based on both the standard and novel embedded validity indicators). Although ND accounted for a small percentage of variance in the prediction of invalid performance, negative consequences (e.g., extended time out of sports) of incorrect decision-making should be considered for those with neurodevelopmental conditions. Also, reasons for the overall increase noted here, such as decreased motivation, “sandbagging”, or disability-related cognitive deficit, require additional investigation.

Cognitive Assessment via Telepractice versus Face-to-Face Administration: A Pilot Study

To investigate the stability of cognitive assessment via the Immediate Post Concussion Assessment and Cognitive Testing (ImPACT) in using telepractice versus face-to-face delivery.

Symptom profile following cumulative mild traumatic brain injury in early adolescent rugby union players in South Africa

Background. The symptom profiles of young adolescent rugby and non-contact sports were investigated over one sport season. Objectives. To compare the concussion symptom profiles of rugby players with those of non-contact sport players over a sport season. Methods. In a non-equivalent quasi-experimental design, a group of rugby players ( n =99) were compared with a demographically equivalent group of non-contact sport participants ( n =74). The computerised Immediate Post-concussion Assessment and Cognitive Testing (IMPACT) symptom scale was employed to evaluate and compare pre-season and post-season assessment of both groups. Results. Independent comparative analyses revealed that the damaging effects owing to exposure to concussive and sub-concussive incidents appear to be more pronounced in the rugby group in terms of symptomatic presentation compared with the controls. Conclusion. The damaging effects are compounded during a rugby season as a result of sub-concussive and concussive events.

Multiple Past Concussions in High School Hockey Players: Examining Cognitive Functioning and Symptom Reporting.

To investigate (1) if there are meaningful differences in baseline preseason cognitive functioning or symptom reporting between high school ice hockey players with and without prior concussions and (2) determine which health history variables predict symptom reporting. Cross-sectional study. High schools across the state of Maine. Participants were 1616 male high school ice hockey players (mean age = 15.6 years; SD = 1.5 years) who completed baseline testing between 2009 and 2015. Athletes were grouped according to their self-reported concussion history [0 (n = 1136), 1 (n = 321), 2 (n = 112), or 3+ (n = 47) previous concussions]. Cognitive functioning was measured by the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) battery, and symptom ratings were obtained from the Post-Concussion Symptom Scale. There were no statistically significant differences between groups in cognitive functioning as measured by ImPACT. The group with ≥3 prior concussions endorsed higher total symptom scores, but the effect sizes were small and not statistically significant. In a multivariate model, prior treatment for headaches (not necessarily migraines), prior treatment for a psychiatric condition, and prior treatment for substance/alcohol use all significantly predicted total symptom scores, with concussion history being the weakest independent predictor. Players with a history of prior concussions performed similarly to players with no prior concussions on cognitive testing. Health history factors were more strongly associated with symptom reporting than concussion history.

The Ketogenic Diet in the Treatment of Post-concussion Syndrome-A Feasibility Study.

Concussion is the most common form of mild traumatic brain injury (mTBI). Although most patients' symptoms resolve within a month, patients with post-concussion syndrome (PCS) may continue to experience symptoms for years and have limited treatment options. This pilot study assessed the feasibility and symptom-related effects of a ketogenic diet (KD) in patients with PCS symptoms. The Ketogenic Diet in Post-Concussion Syndrome (KD-PCS) was a single-arm trial of a 2-month KD high in non-starchy vegetables and supplemented with medium-chain triglyceride (MCT) oil. Macronutrient targets were ≥70% fat, ≤10% carbohydrate, and the remainder as protein as energy. We assessed feasibility by daily self-reported measure of urine acetoacetate and collection of 3-day food records and serum beta-hydroxybutyrate at multiple timepoints. We assessed symptoms by administering the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) and Modified Balance Error Scoring System (M-BESS) at baseline and month 2 and the Post-Concussion Symptom Scale (PCSS) at baseline, month 1, and month 2. Fourteen participants enrolled in the KD-PCS. Twelve participants completed the study and 11 implemented the KD (73% fat, 9% carbohydrate, and 18% protein) and achieved ketosis. One participant complained of MCT-related diarrhea that resolved and another reported nausea and fatigue that resulted in withdrawal from the study. Among compliant participants, the visual memory domain of the ImPACT improved by 12 points (p = 0.02) and PCSS scores improved by 9 points, although not statistically significant. This pilot trial suggests that the KD is a feasible experimental treatment for PCS and justifies further study of its efficacy.

Estimated age of first exposure to American football and outcome from concussion.

To examine the association between estimated age at first exposure (eAFE) to American football and clinical measures throughout recovery following concussion. Participants were recruited across 30 colleges and universities as part of the National Collegiate Athletic Association (NCAA)-Department of Defense Concussion Assessment, Research and Education Consortium. There were 294 NCAA American football players (age 19 ± 1 years) evaluated 24-48 hours following concussion with valid baseline data and 327 (age 19 ± 1 years) evaluated at the time they were asymptomatic with valid baseline data. Participants sustained a medically diagnosed concussion between baseline testing and postconcussion assessments. Outcome measures included the number of days until asymptomatic, Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) composite scores, Balance Error Scoring System (BESS) total score, and Brief Symptom Inventory 18 (BSI-18) subscores. The eAFE was defined as participant's age at the time of assessment minus self-reported number of years playing football. In unadjusted regression models, younger eAFE was associated with lower (worse) ImPACT Visual Motor Speed (R 2 = 0.031, p = 0.012) at 24-48 hours following injury and lower (better) BSI-18 Somatization subscores (R 2 = 0.014, p = 0.038) when the athletes were asymptomatic. The effect sizes were very small. The eAFE was not associated with the number of days until asymptomatic, other ImPACT composite scores, BESS total score, or other BSI-18 subscores. Earlier eAFE to American football was not associated with longer symptom recovery, worse balance, worse cognitive performance, or greater psychological distress following concussion. In these NCAA football players, longer duration of exposure to football during childhood and adolescence appears to be unrelated to clinical recovery following concussion.