040 Effect of youth sports traumatic brain injury laws on the incidence of catastrophic traumatic brain injuries among U.S. high school football athletes

Statement of Purpose

Between 2009 and 2014, all 50 states and the District of Columbia (DC) passed legislation addressing sports-related traumatic brain injuries (TBIs). Prior research demonstrated a reduction in mild TBI (concussion) incidence after this legislation passed, but the effect of these state-level laws on catastrophic TBI have not been examined. The purpose of this study is to examine the impact of state concussion legislation on the incidence of catastrophic TBIs among high school football players from academic year 2000/01 through 2019/20.

Methods/Approach

This state-by-year analysis utilized surveillance data from the National Center for Catastrophic Sport Injury Research, the National Federation of State High School Associations and the Policy Surveillance Program. The main exposure was whether or not a law was enacted in a given year in each state/DC. The main outcome was incidence of catastrophic TBI per 100,000 athlete-seasons in each state each year. Incidence rate ratios (IRR) and 95% confidence intervals (CI) were estimated from negative binomial regression models. We used generalized estimating equations to account for auto-correlation within state over time. A sensitivity analysis was performed to determine if there was a lagged effect of legislative enactment.

Results

Over the 20-year period, 248 catastrophic TBIs were captured in 44 states across 22,185,519 athlete-seasons (Incidence rate=1.12/100,000 athlete-seasons). The incidence of catastrophic TBI was lower in time periods post-enactment relative to the same jurisdiction pre-enactment: IRR = 0.84 (95%CI: 0.66, 1.08). In sensitivity analyses, there did not appear to be discernable lagged effect, indicating that the effect of legislation was essentially immediate.

Conclusions

State legislation addressing TBI was associated with an estimated 16% reduction in catastrophic TBI in high school football.

Significance

Based on these observational data and previously documented effects for mild TBI, it is probable that state TBI legislation reduced the incidence of catastrophic TBI.