Association Between Excessive Daytime Sleepiness and Severe Hypoglycemia in People With Type 2 Diabetes: The Edinburgh Type 2 Diabetes Study

OBJECTIVE: Sleep-disordered breathing and sleepiness cause metabolic, cognitive, and behavioral disturbance. Sleep-disordered breathing is common in type 2 diabetes, a condition that requires adherence to complex dietary, behavioral, and drug treatment regimens. Hypoglycemia is an important side effect of treatment, causing physical and psychological harm and limiting ability to achieve optimal glycemic control. We hypothesized that sleep disorder might increase the risk of hypoglycemia through effects on self-management and glucose regulation. RESEARCH DESIGN AND METHODS: People with type 2 diabetes (n = 898) completed questionnaires to assess sleep-disordered breathing, daytime sleepiness, and occurrence of severe hypoglycemia. RESULTS: Subjects who scored highly on the Epworth Sleepiness Scale were significantly more likely to have suffered from severe hypoglycemia. This was a significant predictor of severe hypoglycemia in regression analysis including the variables age, sex, duration of diabetes, HbA(1c), BMI, and treatment type. CONCLUSIONS: Daytime sleepiness may be a novel risk factor for hypoglycemia.