Back to Bibliography
Page
Association of Sleep Time With Diabetes Mellitus and Impaired Glucose Tolerance.
ABSTRACT
Background: Experimental sleep restriction causes impaired glucose tolerance
(IGT); however, little is known about the metabolic effects of habitual sleep restriction. We assessed the
cross-sectional relation of usual sleep time to diabetes mellitus (DM) and IGT among participants in the Sleep
Heart Health Study, a community-based prospective study of the cardiovascular consequences of sleep-disordered
breathing.
Methods: Participants were 722 men and 764 women, aged 53 to 93 years. Usual sleep time was obtained by
standardized questionnaire. Diabetes mellitus was defined as a serum glucose level of 126 mg/dL or more (7.0
mmol/L) fasting or 200 mg/dL or more (11.1 mmol/L) 2 hours following standard oral glucose challenge or
medication use for DM. Impaired glucose tolerance was defined as a 2-hour postchallenge glucose level of 140
mg/dL or more (7.8 mmol/L) and less than 200 mg/dL. The relation of sleep time to DM and IGT was examined
using categorical logistic regression with adjustment for age, sex, race, body habitus, and apnea-hypopnea
index.
Results: The median sleep time was 7 hours per night, with 27.1% of subjects sleeping 6 hours or less
per night. Compared with those sleeping 7 to 8 hours per night, subjects sleeping 5 hours or less and 6 hours
per night had adjusted odds ratios for DM of 2.51 (95% confidence interval, 1.57-4.02) and 1.66 (95%
confidence interval, 1.15-2.39), respectively. Adjusted odds ratios for IGT were 1.33 (95% confidence
interval, 0.83-2.15) and 1.58 (95% confidence interval, 1.15-2.18), respectively. Subjects sleeping 9 hours
or more per night also had increased odds ratios for DM and IGT. These associations persisted when subjects
with insomnia symptoms were excluded.
Conclusions: A sleep duration of 6 hours or less or 9 hours or more is associated with increased
prevalence of DM and IGT. Because this effect was present in subjects without insomnia, voluntary sleep
restriction may contribute to the large public health burden of DM.
