Association of short sleep duration with impaired glucose tolerance or diabetes mellitus

Aims/Introduction: To examine the cross-sectional relationship between sleep duration and impaired glucose tolerance (IGT), including diabetes mellitus (DM), we analyzed a large-scale healthy workers database in Japan. Materials and Methods: We examined the baseline database of 4143 participants (3415 men and 728 women) aged 19-69years. Sleep duration of participants was categorized into four groups: <6, 6 to <7, 7 to <8 and ≥8h. The physical activity of each participant was classified according to the International Physical Activity Questionnaire (IPAQ). We defined IGT including DM (IGT/DM) in the present study according to previous studies as follows: fasting blood sugar level ≥110mg/dL, or if <8h after meals ≥140mg/dL, or on medication for diabetes mellitus, or those diagnosed as having DM. Logistic regression was applied to estimate the odds ratio (OR) to examine the relationship between IGT/DM, sleep duration and other related factors. Results: The number of participants with IGT/DM was 402 (9.7%). The factors that significantly associated with IGT/DM were age (OR 1.08, 95% confidence interval [CI] 1.07-1.10, P<0.001), high blood pressure (OR 1.94, CI 1.52-2.47, P<0.001), and <6h of sleep duration in comparison with 6 to <7h sleep (OR 2.32, CI 1.18-4.55, P=0.015). The associations of difficulty in sleep initiation, IPAQ classification, current smoking and alcohol intake with IGT/DM were not statistically significant. Conclusions: Our results showed that shorter sleep duration (<6h of sleep duration per night) was associated with a risk of IGT/DM independent of other lifestyle habits and metabolic risk factors.