Sleep duration, blood pressure and cardiovascular outcomes in the middle-aged and the elderly

Short or long sleep duration is associated with hypertension in middle-aged populations. However, this association, and its possible effect on cardiovascular outcomes, is not established in older adults, despite age-related changes in the role of systolic (SBP) and diastolic (DBP) blood pressure as cardiovascular risk factors, and the increased predictive role of pulse pressure (PP) in the elderly. We investigated the association of sleep duration with BP levels by 24-h ambulatory BP monitoring (ABPM) and with incident cardiovascular outcomes.

828 participants (mean age 71 years, 60% women) were evaluated. Self-reported short sleep was defined as the lowest quintile (≤7 h) and long sleep as the highest quintile (>10 h); intermediate duration was reference. Outcomes were ischemic stroke, myocardial infarction, cardiovascular death, and composite outcome (any of the 3).

Long sleepers had substantially higher daytime and 24-h PP than the reference group (both P < 0.05). There were no differences in SBP and DBP values. Over 11.3 years of follow-up, 214 (25.8%) participants developed cardiovascular events. Long sleep was independently associated with ischemic stroke (adjusted hazard ratios [aHR] 1.76, 95% confidence interval [CI], 1.02-3.04; p = 0.044), cardiovascular death (aHR 1.56, 95% CI, 1.03-2.37; p = 0.035) and composite outcome (aHR 1.41, 95% CI, 1.01-1.98; p = 0.046). PP was also independently associated with cardiovascular events. Short sleep was associated with increased PP in the elderly.

Long sleep duration was associated with increased PP and subsequent cardiovascular events, suggesting the importance of PP for cardiovascular risk in the middle-aged and elderly long sleepers.