The relationship of sleep duration and insomnia to risk of hypertension incidence: a meta-analysis of prospective cohort studies

Abstract

To assess whether habitual sleep duration or insomnia increase the incidence of hypertension. PubMed, EMBASE and Cochrane were searched without language restriction. Prospective cohort studies of adults with at least a 1-year follow-up duration were included. Habitual sleep duration or symptoms of insomnia were assessed as baseline exposure, and the outcome was incidence of hypertension. Subgroup, meta-regression and sensitivity analyses were conducted to assess heterogeneity, and Egger's test was used to assess publication bias. Eleven studies (17 cohorts) were included. Short sleep duration, sleep continuity disturbance (SCD), early-morning awakening (EMA) and combined symptoms of insomnia increased the risk of hypertension incidence (the relative risks (95% confidence intervals) were 1.21 (1.05-1.40) for short sleep duration, 1.20 (1.06-1.36) for SCD, 1.14 (1.07-1.20) for EMA and 1.05 (1.01-1.08) for combined insomnia symptoms). Less evidence exists to support conclusions about the association between long sleep duration or difficulty falling asleep (DFA) and hypertension incidence. No obvious heterogeneity or publication biases were found. Our meta-analysis demonstrates that short sleep duration and single/combined symptoms of insomnia (except DFA) are associated with an increased risk of hypertension incidence. It is important to consider sleep duration and insomnia during hypertension prevention and treatment. More laboratory studies on potential mechanisms and prospective observational studies with objective measures of sleep are needed.

Figure 1

Flowchart of study selection.

Figure 2

Forest plot of sleep duration and risk of hypertension incidence. (a) Short sleep duration. (b) Long sleep duration. A full-colour version of this figure is available at Hypertension Research online.

Figure 3

Funnel plot of selected studies. Funnel plot describing the relationship between effect size and s.e. of effect, with possible missing studies imputed. LnRR, natural logarithm of relative risk; vertical line, mean effect size; dashed line, pseudo 95% confidence limits. (a) Short sleep duration. (b) Long sleep duration. (c) Difficulty falling asleep (DFA). (d) Sleep continuity disturbance (SCD). (e) Early-morning awakening (EMA). (f) Combination of all symptoms of insomnia. A full-colour version of this figure is available at Hypertension Research online.

Figure 4

Forest plot of symptoms of insomnia and risk of hypertension incidence. (a) DFA (b) SCD. (c) EMA. (d) Combination of all symptoms of insomnia. A full-colour version of this figure is available at Hypertension Research online.