Comparative Effectiveness of Roux-en Y Gastric Bypass Versus Vertical Sleeve Gastrectomy for Sustained Remission of Type 2 Diabetes Mellitus

Background: Bariatric surgery results in rapid weight loss and resolution of comorbidities such as type 2 diabetes mellitus (T2DM). We aimed to determine whether the type of surgical procedure—vertical sleeve gastrectomy (VSG) versus Roux-en-Y gastric bypass (RYGB)—was associated with sustained remission from T2DM, and to identify other independent predictors of sustained remission. Methods: Using the IBM MarketScan database of privately insured patients in the United States, we performed a retrospective cohort study on individuals aged 18-65 y with T2DM on hypoglycemic medication, who underwent either VSG or RYGB from 2010 to 2016. Remission was defined as no refill of antidiabetic medication 180 d after a patient's medication was expected to run out and recurrence as medication refill after at least 180 d of remission. Results: Of 5119 patients in our cohort, 4127 (81%) experienced remission of T2DM, and 816 (19.8%) of the 4127 patients experienced recurrence. Patients who underwent RYGB had a 24% (HR = 1.24, 95% CI: 1.16, 1.32) increased probability of achieving remission compared with VSG. RYGB had a 36% (HR = 0.64, 95% CI: 0.55, 0.74) decreased risk of recurrence compared with VSG. A higher number of diabetic medications at the time of surgery and a higher Charlson index score were associated with decreased probability of remission and an increased risk of recurrence of T2DM. Conclusions: While both procedures are initially effective, RYGB may be better than VSG at providing lasting remission of T2DM.