Remission of Type 2 Diabetes Mellitus (T2DM) after Sleeve Gastrectomy (SG), One-Anastomosis Gastric Bypass (OAGB), and Roux-en-Y Gastric Bypass (RYGB): A Systematic Review

Background and Objectives: The three most widely performed bariatric surgeries are Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG), and one-anastomosis gastric bypass (OAGB). Aside from the benefits of weight loss, current findings suggest that these procedures can also induce remission of T2DM (type 2 diabetes mellitus). There are limited data that directly compare these three procedures. This study aims to compare the short-term and long-term remission of T2DM after RYGB, SG, and OAGB. Materials and Methods: Three databases (Embase, PubMed, and Cochrane) were searched for randomised controlled trials, prospective studies, and retrospective studies that compared the effects of RYGB, SG, and OAGB on T2DM remission. Studies published between 2001 and 2022 were analysed. Only patients with T2DM and who had primary bariatric surgery were included. Results: After applying the inclusion and exclusion criteria, seven articles were included in the review. It was found that all three procedures had comparable T2DM remission. RYGB was noted to have the highest complication rate when compared to SG and OAGB. Importantly, it was noted that other predictive factors such as age, duration of diabetes, baseline HbA1c, BMI, and use of antidiabetic medication play a crucial role in T2DM remission. Conclusions: This systematic literature review confirms the existing data that all three bariatric surgeries induce remission of T2DM. Increasing in popularity, OAGB had comparable outcomes to RYGB and SG in inducing T2DM remission. In addition to the choice of bariatric surgery, there are other independent predictive factors that have an impact on T2DM remission. Further studies with larger sample sizes, longer follow-up periods, and studies that control confounding factors are required in this field.