Abstract
AIMS: To examine the association between duration and quality of sleep and the prevalence of undiagnosed and clinically identified diabetes mellitus and pre-diabetes in a nationally representative sample. METHODS: Cross-sectional study of 2285 participants ≥ 30 years old and without diagnosed sleep disorders from the National Health and Nutrition Examination Survey (2005-2008). The primary exposures were sleep duration and quality. Sleep quality was assessed by questionnaire using trouble initiating sleep, trouble maintaining sleep, and waking up too early. The primary outcomes were clinically identified and undiagnosed pre-diabetes and diabetes as defined by the American Diabetes Association using fasting plasma glucose (5.6-6.9 mmol/l = pre-diabetes; ≥ 7.0 mmol/l = diabetes). Multivariate logistic regression was used to test the association between sleep quality, sleep duration and glycaemic status. RESULTS: After adjustment for socio-demographic characteristics and health behaviors, sleeping ≤ 5 h/night was associated with clinically identified pre-diabetes (odds ratio 2.06, 95% CI 1.00-4.22 vs. 7 h). Both trouble maintaining sleep ≥ 5 times/month (odds ratio 3.50, 95% CI 1.30-9.45) and waking up too early ≥ 5 times/month (odds ratio 2.69, 95% CI 1.21-5.98) were also significantly associated with increased risk of clinically identified pre-diabetes. Trouble initiating sleep and sleeping ≥ 9 h/night were not found to be associated with having diabetes. CONCLUSIONS: Only clinically identified pre-diabetes was associated with trouble maintaining sleep, waking up too early, and short sleep. No other relations were found to be significant. Findings suggest that poor sleep quality and short sleep duration were more strongly associated with clinically identified pre-diabetes than 7-8 hours per day.