Highly increased risk of type 2 diabetes in patients with binge eating disorder and bulimia nervosa

OBJECTIVE: We aimed to examine the prevalence and incidence of type 2 diabetes (T2D) in a large patient cohort treated for binge eating disorder (BED), bulimia nervosa (BN), and anorexia nervosa. METHOD: Patients (N = 2,342) treated at the Eating Disorder Unit of Helsinki University Central Hospital over the period up to 16 years were compared with matched general population controls (N = 9,368) in three stages: before entering to the treatment for an eating disorder, after the entrance until the end of the study period, and combined any time before, during, and after the treatment. The study population was linked with the oral TSD medication data of 17 years from The Medical Reimbursement Register. Data were analyzed using conditional and Poisson regression models. RESULTS: Before entering to the treatment for eating disorders, the risk of T2D was substantially increased in patients compared with controls (OR 6.6, 95% CI 4.0-10.7). At the end of the study period, the lifetime prevalence of T2D was 5.2% among patients, 1.7% among controls (OR 3.4, 95% CI 2.6-4.4), and in male patients, it was significantly higher compared with females. Of those treated for BED, every third had T2D by the end of the study period (OR 12.9, 95% CI 7.4-22.5), whereas the same was true for 4.4% of those with BN (OR 2.4, 95% CI 1.7-3.5). DISCUSSION: Our findings provide strong support for the association between T2D and clinically significant binge eating. Disturbed glucose metabolism may contribute to the onset and maintenance of BED and BN.