Relationship of sleep duration with all-cause mortality and cardiovascular events: A systematic review and dose-response meta-analysis of prospective cohort studies

Background--effects of extreme sleep duration on risk of mortality and cardiovascular outcomes remain controversial. we aimed to quantify the dose-response relationships of sleep duration with risk of all-cause mortality,total cardiovascular disease,coronary heart disease,and stroke. methods and results--pubmed and embase were systematically searched for prospective cohort studies published before december 1,2016,that examined the associations between sleep duration and at least 1 of the 4 outcomes in generally healthy populations. u-shaped associations were indicated between sleep duration and risk of all outcomes,with the lowest risk observed for ≈7-hour sleep duration per day,which was varied little by sex. for all-cause mortality,when sleep duration was < 7 hours per day,the pooled relative risk (rr) was 1.06 (95% ci,1.04-1.07) per 1-hour reduction; when sleep duration was > 7 hours per day,the pooled rr was 1.13 (95% ci,1.11-1.15) per 1-hour increment. for total cardiovascular disease,the pooled rr was 1.06 (95% ci,1.03-1.08) per 1-hour reduction and 1.12 (95% ci,1.08-1.16) per 1-hour increment of sleep duration. for coronary heart disease,the pooled rr was 1.07 (95% ci,1.03-1.12) per 1-hour reduction and 1.05 (95% ci,1.00-1.10) per 1-hour increment of sleep duration. for stroke,the pooled rr was 1.05 (95% ci,1.01-1.09) per 1-hour reduction and 1.18 (95% ci,1.14-1.21) per 1-hour increment of sleep duration. conclusions--our findings indicate that both short and long sleep duration is associated with an increased risk of all-cause mortality and cardiovascular events. © 2017 the authors.