Background: Type 1 diabetes patients, although typically lean, experience an increased prevalence of obesity, and bariatric surgery is considered in severe cases. Bariatric surgery in such patients leads to significant weight loss and decreased insulin requirements; however, effects on glycemic control remain discussed. We assessed, in obese patients with type 1 diabetes, the effects of bariatric surgery upon body weight, body composition, and glycemic control, including the occurrence of hypoglycemic events.
Methods: Thirteen obese patients with type 1 diabetes who underwent bariatric surgery (Roux-en-Y gastric bypass n = 6, sleeve gastrectomy n = 7) were matched with obese patients without diabetes and with type 2 diabetes patients during 12 months of follow-up. Outcomes included body weight, DXA-assessed body composition, HbA1c, and incidence of hypoglycemia.
Results: At 12 months, median surgery-induced weight loss was 27.9 % (21.1-33.3), 26.1 % (24.8-29.7), and 27.5 % (21.8-32.1) in patients with type 1 diabetes, type 2 diabetes, and without diabetes, respectively, with no significant differences across the groups. Similar findings were observed for body fat changes. At 12 months, median HbA1c decreased from 8.3 to 7.6 % in type 1 diabetes patients versus 8.0 to 5.9 % in type 2 diabetes patients (P = 0.04 between the groups). In type 1 diabetes patients, the number of reported minor hypoglycemia increased transiently only at 6 months. Two patients reported severe hypoglycemia (one episode each).
Conclusions: Type 1 diabetes patients benefit from bariatric surgery in terms of weight loss and glycemic control. Close monitoring of insulin therapy appears warranted to prevent minor hypoglycemia in the first months post-surgery.
Keywords: Body composition; Hypoglycemia; Metabolic control; Obesity; Type 1 diabetes.