To examine the association between estimated age of first exposure (eAFE) to American football and clinical measures throughout recovery following concussion.

In collegiate football players, we reported no association between eAFE and baseline neurocognitive function. It is possible that neurocognitive deficits from earlier eAFE to American football, if present, are sufficiently compensated for in otherwise healthy individuals, but when faced with  concussion, earlier eAFE may associate with longer symptom recovery, worse cognitive performance, or greater psychological distress.

Participants were recruited as part of the NCAA–DoD Concussion Assessment, Research and ºÃÉ«ÏÈÉú (CARE) Consortium. There were 340 NCAA football players (age=18.9±1.4years) who were evaluated 24-48 hours following concussion and had valid baseline data and 360 (age=19.0±1.3years) who were evaluated at the time they were asymptomatic and had valid baseline data. Participants sustained a medically-diagnosed concussion between baseline testing and post-concussion assessments. Outcome measures included the number of days until asymptomatic, Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) composite scores, Brief Symptom Inventory 18 (BSI-18) sub-scores, and Hospital Anxiety and Depression Scale (HADS) scores. The eAFE was defined as the participant’s age at the time of assessment minus the self-reported number of years playing football. 

Results of generalized linear modeling suggested that younger eAFE was only associated with lower (better) BSI-18 Somatization (estimate=0.046, p=0.046, CI=0.001-0.091) and BSI-18 Anxiety sub-scores (estimate=0.053, p=0.039, CI=0.003-0.104) at 24-48 hours. The eAFE was not associated with days until asymptomatic, ImPACT composite scores, HADS scores, or other BSI-18 sub-scores.

Earlier eAFE to football was not associated with longer symptom recovery, worse cognitive performance, or greater psychological distress following concussion. Longer duration of exposure to football during childhood and adolescence appears to be unrelated to clinical recovery following concussion.