Original Contribution Sleep Duration and Coronary Heart Disease Mortality Among Chinese Adults in Singapore: A Population-based Cohort Study

While some studies have found a positive association between both short and long sleep durations and cardio-vascular disease (CVD), others have found an association only with a long or short sleep duration. In addition, there are limited data from non-Western populations on this topic. The authors examined the association between sleep duration and coronary heart disease (CHD) mortality among Chinese adults in Singapore (1993–2006), performing a prospective cohort study among 58,044 participants aged 45 years (55.9 % women) without preexisting CVD. The main outcome of interest was CHD mortality (n 1,416). The authors found both short and long sleep durations to be positively associated with CHD mortality, independent of smoking, alcohol intake, and body mass index. Compared with persons with a sleep duration of 7 hours (referent), the multivariable relative risk of CHD mortality for a sleep duration of5 hours was 1.57 (95 % confidence interval: 1.32, 1.88); for a sleep duration of 9 hours, it was 1.79 (95 % confidence interval: 1.48, 2.17). This association persisted in subgroup analyses by sex and body mass index. In a population-based cohort of Chinese adults from Singapore, sleep durations of5 hours and 9 hours (versus 7 hours) were modestly associated with CHD mortality. These results suggest that sleep duration may be an important marker for CVD. Asian continental ancestry group; cardiovascular diseases; coronary disease; mortality; Singapore; sleep Abbreviations: BMI, body mass index; CHD, coronary heart disease; CI, confidence interval; CVD, cardiovascular disease