Association of sleep duration, lifestyle habits, and motor vehicle accident mortality-A prospective cohort study.

OBJECTIVES: While insufficient sleep is known to contribute to motor vehicle accident (MVA) mortality, limited research has focused on the impact of self-reported sleep duration and quality. This study aims to investigate the relationship between sleep duration, sleep quality, and MVA mortality. METHODS: In a cohort of 482,507 participants aged 20 years or older, medical screenings were conducted from 1996 to 2017. Sleep characteristics, including self-reported duration, quality, and sleeping pill use, were assessed via self-reported questionnaires. MVA mortality was identified using International Classification of Diseases-9 and ICD-10 codes. Cox proportional hazards models were applied to calculate hazard ratios (HRs) for MVA mortality. RESULTS: There were 37,541 deaths, including 791 due to accidents. Approximately 70% of participants reported sleeping 6-8 hours per night, while 20.2% reported 4-6 hours, 1.2% less than 4 hours, and 8.7% more than 8 hours. After adjusting for covariates, participants with a shorter sleep duration (4-6 hours) had a 30% increased risk of MVA mortality compared with those with 6-8 hours (HR: 1.30; 95% CI: 1.09-1.55). Those with sleep durations exceeding 8 hours had a similar 31% increase in risk (HR: 1.31; 95% CI: 1.05-1.64). This risk was further elevated among smokers, frequent alcohol drinkers, and sleeping pill users. CONCLUSIONS: Both self-reported shorter sleep durations (less than 6 hours) and longer sleep durations (more than 8 hours) are associated with elevated MVA mortality risk, forming a U-shaped relationship. This risk is amplified among smokers, frequent alcohol consumers, and sleeping pill users.