Objectives: An association of sleep with cardiovascular disease has been suggested. We analyzed the association of sleep duration with carotid intima-media thickness (IMT) as measure of generalized atherosclerosis.
Methods: IMT of the common carotid arteries was measured in 2437 participants of the Study of Health in Pomerania (SHIP). Participants indicated their daily sleep duration as sum of night and afternoon sleep.
Results: There was a J-shaped association of sleep duration (5 to 11/12h) with IMT. In this association, IMT values were lowest among subjects with an average sleep duration of 7-8h (0.76+/-0.15 and 0.79+/-0.16 mm, respectively) but increased with shorter and, still more so, with longer sleep duration. Subjects with only 5h sleep showed age- and sex-adjusted differences of 0.042 mm IMT (95% confidence interval 0.008-0.076 versus 8h sleep). IMT values were still greater among subjects with 11-12h sleep (adjusted differences versus 8h sleep 0.084 mm [0.040-0.128] IMT). Further adjustment for lifestyle indicators, socioeconomic determinants, and biological variables attenuated these differences, but they remained significant.
Conclusions: Both longer and shorter sleep duration is associated with an increased risk of atherosclerosis. These findings support the hypothesis that sleep is related to cardiovascular disease.