Sleep Duration and Risk of Fatal Coronary Heart Disease, Sudden Cardiac Death, Cancer Death, and All-Cause Mortality

Background: Sleep duration has been shown to be associated with all-cause mortality, however its relationship with cause-specific fatal events remains uncertain. We examined the relationship between sleep duration and risk of fatal coronary heart disease (CHD), sudden cardiac death, cancer related death and all-cause mortality. Methods Sleep duration was self-reported at baseline examinations performed between March 20, 1984 and December 5, 1989 in 2,361 men aged 42-61 years old from the Kuopio Ischemic Heart Disease study. Of these 1734 (73.4%) men were free from CHD and cancer at baseline. Results: A total of 802 all cause deaths, 202 fatal coronary heart disease events, 141 sudden cardiac events and 229 cancer related deaths were reported during a median follow-up of 25.9 (IQR: 20.6-28.2) years. Multi-variable adjusted hazard ratios (HR) comparing the top quartile (> 10 hours) of sleep duration versus the bottom quartile (<8 hours) was 1.19 (95% CI: 1.01-1.43) for all-cause mortality, 1.27 (95% CI: 0.88-1.84) for fatal coronary heart disease, 1.20 (95% CI: 0.78-1.86) for sudden cardiac death and 1.29 (95% CI: 0.92-1.80) for cancer death. No differences in association of sleep duration with outcomes were found in clinically relevant subgroups including age, history of coronary heart disease, body mass index, physical activity, and C-reactive protein levels. Conclusion: Longer duration of sleep was associated with significantly increased all-cause mortality. Mechanistic link between these findings remains to be explored further.