Population-based cross-sectional study of sex-specific dose-response associations between night sleep duration and hypertension in Islamic Republic of Iran.

Abstract

Several studies have suggested that sleep disorders have adverse effects on blood pressure. However, the findings remain controversial and only a few studies have investigated the association between sleep duration and hypertension among all age and sex subgroups. To evaluate the dose-response association between sleep duration and blood pressure in the Iranian population using the Ravansar non-communicable disease cohort study. This was a cross-sectional study of 9865 participants aged 35-65 years from the 2014-2017 Ravansar non-communicable disease cohort study. Night sleep duration was classified as ≤5 hours, 6 hours, 7 hours, 8 hours, 9 hours, and ≥10 hours. The association between self-reported sleep duration and hypertension was examined using multivariable logistic regression in STATA version 14. Restricted cubic spline analysis showed the dose-response association between sleep duration and hypertension. The age-adjusted prevalence of hypertension was 16.50% among men, 24.20% among women and 20.50% in the total population. Compared with reference sleep duration (7 hours) in the total population, the multivariable odds ratio [OR (95% CI)] for hypertension was 0.70 (0.55-0.88) for the group with 9 hours sleep duration and 0.90 (0.74-1.09) for the group with ≤5 hours sleep duration. Among pre-menopausal women, we observed an inverse association between 9 hours sleep duration and hypertension [0.62 (0.42-0.90)]. The age-adjusted cubic spline suggested a linear inverse association between sleep duration and prevalence of hypertension among men and the total population and a non-linear association among women. Longer sleep duration (from 9 hours) had a negative association with hypertension. Further studies are needed to identify the risk factors associated with sleep duration and hypertension among the general population in the Islamic Republic of Iran.