Effects of nighttime sleep duration and sex on the association between siesta and hypertension

Abstract

Objective: To examine the association between siesta and hypertension by sex and nighttime sleep duration among Chinese adults aged ≥35 years in Yinzhou, Ningbo City.

Methods: All data were obtained from physical examinations and structured questionnaires. A total of 44, 652 participants were included. Logistic regression models were applied to calculate odds ratios and 95% confidence intervals for the association between siesta and hypertension.

Results: When compared with no siesta, siesta durations of 60∼89 min (OR = 1.10, 95% CI:1.04-1.17) and ≥90 min (OR = 1.21, 95% CI:1.08-1.36) were associated with higher risk of hypertension in women. But no significant association was observed in men. Siesta durations of 30∼59 min (OR = 1.09, 95% CI:1.00-1.19) and 60-89 min (OR = 1.10, 95% CI:1.05-1.16) were associated with hypertension in people with 6∼8 h sleep, and this association appeared seemingly stronger with ≥90 min siesta either in short (<6 h) sleepers (OR = 1.20, 95% CI: 0.99-1.47) or in long (>8 h) sleepers (OR = 1.29, 95% CI: 1.00-1.68). However, in short sleepers, 60∼89 min siesta seemed to be associated with decreased risk of hypertension (OR = 0.95, 95% CI: 0.85-1.06); while in long sleepers, the same range of siesta seemed to be associated with increased risk of hypertension (OR = 1.11, 95% CI: 0.93-1.34).

Conclusion: Long siesta was associated with increased risk of hypertension in women but not in men. Not too long siesta may be related to decreased risk of hypertension in short sleepers but not in people with adequate or even long sleep. These findings warrant further examination with prospective studies and laboratory investigations.

Keywords: Hypertension; Sex difference; Siesta; Sleep.