11.17 Epidemiology of Concussion in the National Football League, 2015–2019

Objective Describe concussion incidence across the National Football League (NFL). Design Descriptive epidemiology study. Setting Concussions sustained during NFL offseason, preseason (PS), regular season (RS), and postseason team-related activities from 2015–2019. Participants Active NFL players. Interventions Focused concussion reduction efforts in 2018, including better-performing helmets, prohibition of use of helmet to initiate contact and other safety-focused rules changes, and player/Club education. Outcome Measures Concussion. Main Results A total 1,301 concussions were identified from 2015–2019 among 1,003 players, including 1,046 (80%) in games, 221 (17%) during in-season practices, and 34 (3%) in offseason and conditioning activities. Of the 221 in-season practice concussions, 175 (79%) occurred in PS practices, with the majority (n=129) occurring during Training Camp. Concussion rates were 0.31/team-game in RS and 0.35/team-game in PS, which were higher than practice rates (RS: 0.01/team-practice; PS: 0.05/team-practice). Notably, the average annual incidence of in-season concussions during practices and games decreased by 18% from 273.3 in 2015–2017 to 223.5 in 2018–2019 (p<0.01), driven by a 23% decrease in game concussions (2015–2017: 230.7 vs. 2018–2019: 177.0; p<0.01). This decrease followed the focused concussion reduction efforts implemented in 2018. In RS games most concussions were sustained on running and passing plays (n=119/season), but the highest average rate per play was on kickoffs (0.69/100 plays). Conclusions Concussions in the NFL are a key focus for player safety. Concussion reduction strategies implemented prior to 2018 led to a sustained decrease in concussion incidence, providing a new benchmark from which to work toward further reduction.