Abstract
Sleep patterns are important predictors of long-term health outcomes. We investigated the associations of sleep duration, sleep regularity, and their combinations with all-cause mortality and cardiovascular events in a large Korean cohort, including sex-specific analyses. This prospective cohort study included 9,641 adults aged 40-69 years from the Ansung-Ansan cohort in Korea. Participants were categorized by self-reported sleep duration (< 7 h, 7-8 h, or > 8 h) and regularity (regular vs. irregular). Outcomes included all-cause mortality and major adverse cardiovascular events (MACE) over a median follow-up of 186 months, during which 1,095 deaths and 811 MACE occurred. Sleep duration > 8 h was associated with increased all-cause mortality (adjusted hazard ratio [HR], 1.27; 95% confidence interval [CI], 1.04-1.54). Combined analysis showed higher mortality in those with < 7 h and irregular sleep (adjusted HR, 1.28; 95% CI, 1.04-1.58) and > 8 h and regular sleep (adjusted HR, 1.26; 95% CI, 1.01-1.58). In sex-specific analyses, sleep duration and regularity were differentially associated with mortality. In women, > 8 h of irregular sleep was associated with increased risk, while in men, < 7 h of irregular or > 8 h of regular sleep showed similar associations. These findings support tailored strategies considering both sleep characteristics and sex.