A Paired Comparison of Initial and Recurrent Concussions Sustained by US High School Athletes Within a Single Athletic Season

Objective: To compare initial and recurrent concussions regarding average number of days between concussions, acute concussion symptoms and symptom resolution time, and return to play time. Setting/Participants: High school athletes sustaining multiple concussions linked within sport seasons drawn from a large sports injury surveillance study. Design: Retrospective analysis of longitudinal surveillance data. Measures: Number of days between concussions, number of symptoms endorsed, specific symptoms endorsed, symptom resolution time, return to play time. Results: Median time between initial and recurrent concussions was 21 days (interquartile range = 10-43 days). Loss of consciousness, the only significant symptom difference, occurred more frequently in recurrent (6.8%) than initial (1.7%) concussions (P = .04). No significant difference was found in the number of symptoms (P = .84) or symptom resolution time (P = .74). Recurrent concussions kept athletes from play longer than initial concussions (P < .0001); 26.6% of recurrent concussions were season ending. Conclusions: We found that athletes' initial and recurrent concussions had similar symptom presentations and resolution time. Despite these similarities, athletes were restricted from returning to play for longer periods following a recurrent concussion, indicating clinicians are managing recurrent concussions more conservatively. It is probable that concussion recognition and management are superior now compared with when previous studies were published, possibly improving recurrent concussion outcomes.