Association of sleep habits with blood pressure in elderly people.

We investigated the impact of sleep habits on blood pressure (BP) in cross-sectional analyses of 1533 participants aged ≥ 70 without cardiovascular disease or treatment for hypertension, diabetes mellitus, and dyslipidemia. We assessed sleep habits [time in bed (TIB), bed time, and taking sleeping pills], using the Pittsburgh Sleep Quality Index. For groups where TIB was >8 h and <6 h, systolic BP was significantly higher than the group where TIB ranged 6-8 h (134.2 ± 17.5, 134.8 ± 19.6 vs. 130.1 ± 17.7, p < 0.05, p < 0.001, respectively). Systolic BP was significantly higher in the group whose bed time was before 21:00 than that whose bed time was 21:00 or later (136.6 ± 18.6 vs. 132.0 ± 18.4, p < 0.01). Both systolic and diastolic BPs were lower in the group taking sleeping pills (133.2 ± 18.6 vs. 128.1 ± 17.3, p < 0.0001; 75.3 ± 11.5 vs. 73.3 ± 10.7, p < 0.05). Multiple regression analyses revealed that after adjusting for age, gender, body mass index, smoking, and alcohol intake, taking sleeping pills and short or long TIB were significantly associated with systolic BP, whereas bed time was not. These results suggested that inappropriate TIB and sleeping pills were associated with BP in elderly people.