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.


METHODS
We examined the baseline database of 4143 participants (3415 men and 728 women) aged 19-69 years. Sleep duration of participants was categorized into four groups: <6, 6 to <7, 7 to <8 and ≥8 h. 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 ≥110 mg/dL, or if <8 h after meals ≥140 mg/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 <6 h of sleep duration in comparison with 6 to <7 h 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 (<6 h of sleep duration per night) was associated with a risk of IGT/DM independent of other lifestyle habits and metabolic risk factors. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2011.00114.x, 2011).
Cardiovascular Epidemiology, Kyoto Women's University, Kyoto.
Sayuri
S
Katano
Cardiovascular Epidemiology, Kyoto Women's University, Kyoto ; Departments of Health Science.
Yasuyuki
Y
Nakamura
Cardiovascular Epidemiology, Kyoto Women's University, Kyoto.
Aki
A
Nakamura
Medical Statistics, Shiga University of Medical Science, Otsu.
Yoshitaka
Y
Murakami
Department of Health Sciences, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo.
Taichiro
T
Tanaka
Department of Preventive Medicine and Public Health, School of Medicine, Keio University.
Toru
T
Takebayashi
The First Institute of Health Service, Japan Anti-Tuberculosis Association, Tokyo.
Akira
A
Okayama
Departments of Health Science.
Katsuyuki
K
Miura
Department of Preventive Cardiology, National Cardiovascular Center, Suita, Japan.
Tomonori
T
Okamura
Departments of Health Science.
Hirotsugu
H
Ueshima
Diabetes mellitus; Impaired glucose tolerance; Short sleep duration