, findings from a retrospective epidemiologic analysis suggest.
Former professional soccer players included in the analysis also received more dementia-related medication prescriptions than did controls, Daniel F. Mackay, PhD, of the Institute of Health and Wellbeing at the University of Glasgow (Scotland) and his colleagues reported online Oct. 21 in The New England Journal of Medicine.
Overall mortality during a median follow-up of 18 years from study entry at the age of 40 years was 15.4% among 7,676 former players, and 16.5% among 23,028 controls matched based on age, sex, and degree of social deprivation. All-cause mortality was lower among players versus controls before age 70 years, and was higher thereafter, and the mortality rates associated with ischemic heart disease and lung cancer were lower among the players (hazard ratios, 0.80 and 0.53, respectively), the investigators found.
Mortality rates from stroke or cerebrovascular disease were similar in the players and controls (HR, 0.88), they noted.
However, mortality with neurodegenerative disease listed as the primary cause was 1.7% in players versus 0.5% in controls (HR adjusted for competing risks of death, 3.45), they said. The estimated risk of death with neurodegenerative disease was highest among those with Alzheimer’s disease and lowest for those with Parkinson’s disease (HRs, 5.07 and 2.15, respectively).
Dementia-related medications also were prescribed more frequently for players vs. controls (odds ratio, 4.90).
A subgroup analysis showed no significant difference between goalkeepers and outfielders with respect to mortality with neurodegenerative disease listed as a factor (HR, 0.73), but dementia-related medications were prescribed less often to goalkeepers (OR, 0.41).
Concerns about the risk of neurodegenerative diseases among participants in contact sports have been raised, in part because of the recognition of pathologic changes of chronic traumatic encephalopathy among participants across a range of such sports, the investigators explained, noting that data regarding the risk of neurodegenerative disease among former professional soccer players are limited.
The findings of the current study, in terms of lower all-cause mortality up to the age of 70 years, are similar to those in previous studies involving elite athletes across a range of sports, and “may reflect higher levels of physical activity and lower levels of obesity and smoking in elite athletes than in the general population,” they noted.
“In contrast, mortality from neurodegenerative disease was higher among former soccer players, a finding consistent with studies involving former players in the U.S. National Football League,” they added, concluding that the findings, which “may be valuable to inform the management of risks in the sport,” require confirmation in prospective studies.
This study was supported by the Football Association and Professional Footballers’ Association, and by an NHS Research Scotland Career Researcher Fellowship. Dr. Mackay reported having no relevant financial disclosures.
SOURCE: Mackay D et al. N Engl J Med. 2019 Oct 21. doi: 10.1056/NEJMoa1908483.