Abstract
Last decade we observe a rising interest to circadian cycle influence on metabolic disorders and weight control. However, whether changes of sleep characteristics are associated with metabolic syndrome (MS) in the elderly remains unclear.
We selected 88 elderly (60–74 years) patients: 68 with MS and 20 without abdominal obesity and MS. MS was diagnosed according to IDF criteria (2005). Sleep characteristics (bedtime, sleep duration, awakening time, exposure to bright light) were studied by questioning. Data were compared with one-tailed t-test, correlations were calculated using Pearson coefficient.
Bedtime in the elderly significantly correlated with body mass index (r=0,35) and waist circumference (r=0,34). Sleep duration significantly correlated with body mass index (r=0,32). Elderly people with MS went to the bed later (23:35 vs 22:36, p<0,05) and awoke later in the morning (07:53 vs 07:00, p<0,05) than people without abdominal obesity and MS despite the same sleep duration. Moreover, elderly people with MS showed significantly higher prevalence of light at night exposure (71 % vs 25 %, p<0,05).
More late bedtime with stable sleep duration and exposure to light at night are associated with increased body mass and waist circumference, and, thus, may be the factors that contribute to metabolic disorders in elderly.