Abstract
OBJECTIVE: Many NHL teams roster players whose primary responsibility is fighting with opposing players. Over time, these "enforcers" may experience repetitive head impacts (RHI), a risk factor for serious long-term health consequences including neurodegenerative disease. This study examined whether retired NHL enforcers and non-enforcers differ on two long-term health outcomes. METHODS: In this matched cohort study conducted with retrospective, publicly available data, cohorts of former NHL enforcers and non-enforcers were compared on mortality, and CTE diagnosis. NHL players were deemed enforcers (ENFs, n = 239) if listed in a Wikipedia piece entitled "List of NHL enforcers." A randomly selected sample of non-enforcers (non-ENFs, n = 239) were matched to ENFs on year of birth and the first NHL season played. Goalies and players with less than 30 games of NHL experience were excluded. RESULTS: The matching procedure resulted in equivalent cohorts with respect to birth year (1969.9) and first NHL season played (1991.3). Significantly more ENFs had died (n = 23, 9.6% vs. n = 9, 3.8%; p = 0.01) and significantly more ENFs had been given a diagnosis of CTE (n = 7, 2.9% vs. n = 1, 0.4%; p < 0.05). While not statistically significant, age at death averaged 9+ years younger among ENFs (mean = 53.6) compared to non-ENFs (mean = 63). Players born in Canada were over-represented in the ENF cohort. CONCLUSION: This study found higher mortality and more diagnoses of CTE in a cohort of enforcers relative to matched non-enforcers. Given expanding evidence linking RHI to life-threatening long-term health impacts, the NHL must protect players and mandate rule changes that minimize or eliminate fighting.