Minimum Threshold of Bariatric Surgical Weight Loss for Initial Diabetes Remission

Objective: There are few studies testing the amount of weight loss necessary to achieve initial remission of type 2 diabetes (T2DM) following bariatric surgery and no published studies using weight loss to predict initial T2DM remission in sleeve gastrectomy (SG) patients.

Research Design and Methods: Cox proportional hazards models examined the relationship between initial T2DM remission and percent total weight loss (%TWL) after bariatric surgery. Categories of %TWL were included in the model as time-varying covariates.

Results: Patients (N=5,928) were 73% female, 49.8+10.3 years old, had BMI of 43.8+6.92 kg/m², and 57% had Roux-en-Y gastric bypass (RYGB). Over an average follow-up of 5.9 years, 71% of patients experienced initial remission of their T2DM (mean time to remission 1.0 year). Using 0-5% TWL as the reference group in Cox proportional hazards models, patients were more likely to remit with each 5% increase in TWL until 20% TWL (range from HR=1.97 to 2.92). When categories above >25% TWL were examined, all had a likelihood of initial remission similar to 20-25% TWL. Patients who achieved >20% TWL were more likely to achieve initial T2DM remission than patients with 0-5% TWL, even if they were using insulin at the time of surgery.

Conclusions: Weight loss after bariatric surgery is strongly associated with initial T2DM remission; however, above a threshold of 20% TWL, rates of initial T2DM remission did not increase substantially. Achieving this threshold is also associated with initial remission even in patients who traditionally experience lower rates of remission, such as patients taking insulin.