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

OBJECTIVE: To examine the association between estimated age at first exposure (eAFE) to American football and clinical measures throughout recovery following concussion. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Multivariate Base Rates of Low Scores and Reliable Decline on ImPACT in Healthy Collegiate Athletes Using CARE Consortium Norms.

OBJECTIVES: To describe multivariate base rates (MBRs) of low scores and reliable change (decline) scores on Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) in college athletes at baseline, as well as to assess MBR differences among demographic and medical history subpopulations. METHODS: Data were reported on 15,909 participants (46.5% female) from the NCAA/DoD CARE Consortium. MBRs of ImPACT composite scores were derived using published CARE normative data and reliability metrics. MBRs of sex-corrected low scores were reported at <25th percentile (Low Average), <10th percentile (Borderline), and ≤2nd percentile (Impaired). MBRs of reliable decline scores were reported at the 75%, 90%, 95%, and 99% confidence intervals. We analyzed subgroups by sex, race, attention-deficit/hyperactivity disorder and/or learning disability (ADHD/LD), anxiety/depression, and concussion history using chi-square analyses. RESULTS: Base rates of low scores and reliable decline scores on individual composites approximated the normative distribution. Athletes obtained ≥1 low score with frequencies of 63.4% (Low Average), 32.0% (Borderline), and 9.1% (Impaired). Athletes obtained ≥1 reliable decline score with frequencies of 66.8%, 32.2%, 18%, and 3.8%, respectively. Comparatively few athletes had low scores or reliable decline on ≥2 composite scores. Black/African American athletes and athletes with ADHD/LD had higher rates of low scores, while greater concussion history was associated with lower MBRs (p < .01). MBRs of reliable decline were not associated with demographic or medical factors. CONCLUSIONS: Clinical interpretation of low scores and reliable decline on ImPACT depends on the strictness of the low score cutoff, the reliable change criterion, and the number of scores exceeding these cutoffs. Race and ADHD influence the frequency of low scores at all cutoffs cross-sectionally.

Predictors of post-concussion symptom severity in a university-based concussion clinic.

OBJECTIVE: To investigate potential predictors of acute post-concussion symptom severity in a university population. METHODS: Data were obtained from the University of Florida Student Health Care Center Concussion Databank. Symptom severity, measured by the Sport Concussion Assessment Tool - third edition Symptom Evaluation (S3SE), was analyzed at 0-3 (n = 99) and 7-14 days (n = 56) post-concussion. Participants were 99 (56 females; age range: 18-30) students from the University of Florida who had been referred to the center's Concussion Clinic. Independent samples t-test and Mann-Whitney U were used to assess group differences in overall and domain-specific symptom severity, respectively. Hierarchical regressions were used to assess predictors of symptom severity at 0-3 and 7-14 days, as well as residual symptom change between time points. RESULTS: Female sex (ß = .293; p = .002) and history of ADHD (ß = .312; p = .001) predicted greater symptom severity at 0-3 days. History of motion sickness predicted lower symptom severity (ß = -.199; p = .033). ADHD (ß = .284; p = .009) and higher 0-3-day physical symptoms (ß = .552; p < .001) predicted greater symptom severity at 7-14 days. ADHD predicted residual symptom severity change between time points (ß = .433; p = .001). CONCLUSION: ADHD, female sex, and acute physical symptoms (0-3 days) represent risk factors for greater symptom severity in the first two weeks post-concussion among college students.

Socioeconomic Status and Race Outperform Concussion History and Sport Participation in Predicting Collegiate Athlete Baseline Neurocognitive Scores.

OBJECTIVES: The purpose of this study was to assess the contribution of socioeconomic status (SES) and other multivariate predictors to baseline neurocognitive functioning in collegiate athletes. METHODS: Data were obtained from the Concussion Assessment, Research and Education (CARE) Consortium. Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) baseline assessments for 403 University of Florida student-athletes (202 males; age range: 18-23) from the 2014-2015 and 2015-2016 seasons were analyzed. ImPACT composite scores were consolidated into one memory and one speed composite score. Hierarchical linear regressions were used for analyses. RESULTS: In the overall sample, history of learning disability (ß=-0.164; p=.001) and attention deficit-hyperactivity disorder (ß=-0.102; p=.038) significantly predicted worse memory and speed performance, respectively. Older age predicted better speed performance (ß=.176; p<.001). Black/African American race predicted worse memory (ß=-0.113; p=.026) and speed performance (ß=-.242; p<.001). In football players, higher maternal SES predicted better memory performance (ß=0.308; p=.007); older age predicted better speed performance (ß=0.346; p=.001); while Black/African American race predicted worse speed performance (ß=-0.397; p<.001). CONCLUSIONS: Baseline memory and speed scores are significantly influenced by history of neurodevelopmental disorder, age, and race. In football players, specifically, maternal SES independently predicted baseline memory scores, but concussion history and years exposed to sport were not predictive. SES, race, and medical history beyond exposure to brain injury or subclinical brain trauma are important factors when interpreting variability in cognitive scores among collegiate athletes. Additionally, sport-specific differences in the proportional representation of various demographic variables (e.g., SES and race) may also be an important consideration within the broader biopsychosocial attributional model. (JINS, 2018, 24, 1-10).