Sleep duration is associated with an increased risk for the prevalence of type 2 diabetes in middle-aged women – The FIN-D2D survey

Objective To examine the association between sleep duration with type 2 diabetes and abnormal glucose tolerance among middle-aged men and women in Finland. Methods The FIN-D2D survey is a population-based cross-sectional multicentre study in Finland, with 1336 men and 1434 women aged 45–74 participating in the survey during 2004 and 2005. A health examination including an oral glucose tolerance test and sleep questionnaire was performed for all participants. Results There was an independent association between abnormal sleeping times and type 2 diabetes in middle-aged women. Even after adjustments for age, body mass index, sleep apnea probability, smoking, physical activity, and central nervous system-affecting medication, sleep duration of 6h or less or 8h or longer was independently associated with type 2 diabetes. There was no increase in the prevalence of diabetes in middle-aged men with abnormal sleeping times. Conclusion Short (⩽6h) or long (⩾8h) sleep duration is related to an increased risk of type 2 diabetes in middle-aged women but not in men.