Association between sleep duration and metabolic syndrome in a population-based study: Isfahan Healthy Heart Program

BACKGROUND: Recent epidemiologic studies have found that self-reported sleep duration is associated with components of metabolic syndrome (MS) such as obesity, diabetes and hypertension. This relation may be under influence of regional factors in different regions of the world. The association of sleep duration and MS in a sample of Iranian people in the central region of Iran was investigated in this study. METHODS: This cross-sectional study was conducted as a part of the Isfahan Healthy Heart Program (IHHP). A total of 12492 individuals aged over 19 years, 6110 men and 6382 women entered the study. Definition of National Cholesterol Education Program was used to define MS. Sleep duration was reported by participants. Relation between sleep duration with MS was examined using categorical logistic regression in two models; unadjusted and adjusted for age and sex. RESULTS: In our study, 23.5 % of participants had MS. Compared with sleep duration of 7-8 hours per night; sleep duration of less than 5 hours was associated with a higher odds ratio for MS. This association remained significant even after adjustment for age and sex (OR: 1.52; 95%CI: 1.33-1.74). However, sleep duration of 9 hours or more showed a protective association with MS (OR: 0.79; 95%CI: 0.68-0.94). CONCLUSIONS: There was a positive relation between sleep deprivation and MS and its components. This relation was slightly affected by sex and age.