Abstract Body: Background: Unhealthy alcohol use may lead to arrythmias and cardiomyopathy, but its impact on sudden death is not well known. To investigate the association of unhealthy alcohol use with sudden death, we conducted a population-based case-control study in Wake County, a large (~1 million inhabitants), diverse county in North Carolina.
Methods: We screened and adjudicated victims of sudden, unexpected, out-of-hospital deaths in adults aged 18-64 years reported by EMS between 2013 and 2015. We randomly selected sex- and age-matched control patients from a university health system. Characteristics of sudden death victims and controls were ascertained via standardized chart reviews. Unhealthy alcohol use was defined as any evidence of excessive alcohol use or alcohol-related diagnoses. We used logistic regression to estimate odds ratios (ORs) for the association of unhealthy alcohol use and sudden death, adjusting for age, sex, race, and other psychiatric diagnoses, including depression, anxiety, schizophrenia, bipolar disorder, and substance use disorders other than tobacco and alcohol. Smoking status was not available. We also calculated the E-value to estimate the impact of any unmeasured confounders.
Results: We identified 399 sudden death victims of whom 374 (94%) had alcohol use data available. Among these 374 included victims, 256 (68%) were male and 239 (62%) were White with a median age at death of 55 years (IQR 48, 60). The demographic characteristics of the 1114 matched controls were similar to those of sudden death victims. Unhealthy alcohol use was present in 115 (31%) sudden death victims and 27 (2%) controls. In analyses adjusted for demographics only, unhealthy alcohol use was associated with higher incidence of sudden death, with an OR of 17.5 (95% CI 11.4, 27.8). When further adjusted for other psychiatric diagnoses, the OR was 11.2 (95% CI 7.1, 18.0). The calculated E-value was 21.8, meaning an unmeasured confounder would need to be associated with both unhealthy alcohol use and sudden death by 21.8-fold to explain away the observed OR.
Conclusion: Unhealthy alcohol use was strongly associated with higher sudden death risk in working age adults. We could not adjust for smoking in this study; however, the E-value indicates it is unlikely that smoking alone would account for the observed association. Our findings suggest that interventions to reduce unhealthy alcohol use may be an effective strategy to prevent sudden death in working age adults.