Does recovery after sport-related concussion vary by time point in a season? A multi-sport investigation

OBJECTIVE Seasonality, or the specific point in time within a season in which the injury occurs, may have an impact on the recovery following sport-related concussions (SRCs). In a cohort of high school athletes across multiple sports, the authors sought to investigate the impact of seasonality on 1) concussion frequency, 2) acute symptom presentation (initial Post-Concussion Symptom Scale [PCSS] score), and 3) recovery outcomes, including the time to return to learn (RTL), symptom resolution (SR), and return to play (RTP). METHODS A retrospective, single- institution, cohort study was conducted with adolescent athletes aged 14-19 years who sustained an SRC between November 2017 and April 2022 and presented to a multidisciplinary specialty concussion clinic. The time from first practice to the end of the regular season was evenly trichotomized into early, middle, and late season. Teams that participated in the playoffs were included in a subanalysis. One-way ANOVA and independent t-tests were used to compare PCSS scores, RTL, SR, and RTP across seasonality. Univariable and multivariable regressions were used to determine predictors for recovery, defined as total days from initial visit to each outcome. RESULTS Of the 1504 eligible athletes, 620 high school athletes met inclusion criteria; 491 (79.2%) sustained a concussion during the regular season with 73 (14.9%), 136 (27.7%), and 282 (57.4%) concussions occurring in the early, middle, and late seasons, respectively. No differences were seen for initial PCSS score, RTL, SR, or RTP across early-, middle-, and late-season concussions. The initial PCSS score was significantly higher for playoff compared with regularseason concussions (playoffs: 33.4 +/- 27.5; regular season: 23.3 +/- 22.8; t = -1.979, p = 0.048). A subanalysis of playoff concussions (n = 24) compared with regular-season concussions showed that concussion in the playoffs was associated with a higher initial PCSS score in univariable (beta = 0.093, p = 0.048) and multivariable (beta = 0.112, p = 0.014) analyses. CONCLUSIONS The majority of concussions occurred during the late-season period. No difference in acute symptoms or recovery outcomes was seen when comparing the three regular season time points. Playoff concussions were associated with significantly increased symptom scores compared with nonplayoff concussions.