Gender-specific associations of short sleep duration with prevalent and incident hypertension: the Whitehall II Study

Abstract

Sleep deprivation (<or=5 hour per night) was associated with a higher risk of hypertension in middle-aged American adults but not among older individuals. However, the outcome was based on self-reported diagnosis of incident hypertension, and no gender-specific analyses were included. We examined cross-sectional and prospective associations of sleep duration with prevalent and incident hypertension in a cohort of 10,308 British civil servants aged 35 to 55 years at baseline (phase 1: 1985-1988). Data were gathered from phase 5 (1997-1999) and phase 7 (2003-2004). Sleep duration and other covariates were assessed at phase 5. At both examinations, hypertension was defined as blood pressure >or=140/90 mm Hg or regular use of antihypertensive medications. In cross-sectional analyses at phase 5 (n=5766), short duration of sleep (<or=5 hour per night) was associated with higher risk of hypertension compared with the group sleeping 7 hours, among women (odds ratio: 1.72[corrected]; 95% CI: 1.07[corrected] to 2.75[corrected]), independent of confounders, with an inverse linear trend across decreasing hours of sleep (P=0.037[corrected]). No association was detected in men. In prospective analyses (mean follow-up: 5 years), the cumulative incidence of hypertension was 20.0% (n=740) among 3691 normotensive individuals at phase 5. In women, short duration of sleep was associated with a higher risk of hypertension in a reduced model (age and employment) (6 hours per night: odds ratio: 1.56 [95% CI: 1.07 to 2.27]; <or=5 hour per night: odds ratio: 1.94 [95% CI: 1.08 to 3.50] versus 7 hours). The associations were attenuated after accounting for cardiovascular risk factors and psychiatric comorbidities (odds ratio: 1.42 [95% CI: 0.94 to 2.16]; odds ratio: 1.31 [95% CI: 0.65 to 2.63], respectively). Sleep deprivation may produce detrimental cardiovascular effects among women.

Conflict of interest statement

Competing interests: F.P.C. holds the Cephalon Chair, an endowed post at Warwick Medical School, the result of a donation from the company. The appointment to the Chair was made entirely independently of the company and the postholder is free to devise his own programme of research. Cephalon do not have any stake in IP associated with the postholder and the Chair has complete academic independence from the company.