Association between sleep duration and the prevalence of hypertension in an elderly rural population of China.

BACKGROUND:Previous studies have examined an association between sleep duration and hypertension, but the conclusions remain inconsistent. METHODS:We conducted a cross-sectional study in a community-based rural elderly population of Beijing, China. A total of 2397 participants (967 male and 1430 female) completed the survey. Sleep duration was assessed in a face-to-face interview and was self-reported. Hypertension was defined as systolic blood pressure (BP) ≥ 140 mm Hg and/or diastolic BP ≥ 90 mm Hg and/or receiving treatment for hypertension. Multiple logistic regression was used to estimate the association between gender-specific sleep duration and hypertension prevalence. RESULTS:Overall, no significant differences were observed among female participants and the total participants, and the differences were statistically significant only in men. After adjusting for potential confounding variables, the odds ratio (OR) and 95% confidential interval (CI) of having hypertension was 1.33 (1.00, 1.77) in men who slept for ≥9 h compared with those slept for six to eight hours per 24-h period. Furthermore, a one hour nap was associated with less likelihood of hypertension in men compared with those who did not nap, with an adjusted OR (95% CI) of 0.61 (0.41, 0.90). CONCLUSION:In a community-based rural elderly population of China, we found that sleep duration of six to eight hours per 24-h period and a one hour nap were significantly associated with lower risk of hypertension only among male participants after adjustment for potential confounders. Further studies are still needed to determine the relationships between 24-h, nighttime, and daytime sleep duration separately with hypertension, and to explore the biological mechanisms underlying the gender-related association.