Evaluating the Effectiveness and Long-term Outcomes of Roux-en-Y Gastric Bypass vs Gastric Sleeve Bariatric Surgery in Obese and Diabetic Patients: Systematic Review

BACKGROUND: Obesity and type 2 diabetes mellitus (T2DM) are significant contributors to global morbidity, mortality, and rising healthcare costs. Bariatric surgery, particularly Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG), has emerged as a highly effective intervention for weight loss and metabolic control. However, long-term comparative data on sustained weight loss, T2DM remission, and postoperative complications remain inconsistent. STUDY DESIGN: This systematic review compares long-term outcomes of RYGB and SG in patients with obesity and T2DM, emphasizing sustained weight loss, T2DM remission, revisional surgery, and postoperative complications, including GERD, Barrett’s esophagus, and anastomotic leak. A systematic search of PubMed and ScienceDirect identified randomized controlled trials and observational cohort studies from 2005 to 2024. Eligible studies had 5 years or more of follow-up and assessed weight loss, T2DM remission, GERD, and revisional rates in adults undergoing RYGB or SG. Study quality was assessed using the Newcastle-Ottawa Scale and Cochrane Risk of Bias tools. RESULTS: RYGB was associated with more significant long-term weight loss and superior T2DM remission rates. SG had a lower risk of nutritional deficiencies with increased risk of complications requiring surgical revision, particularly GERD, which may progress to Barrett’s esophagus and increase esophageal cancer risk. Revisional surgery occurs frequently post-SG surgery due to weight recurrence and treatment-resistant GERD. In contrast, RYGB revisions were more often due to marginal ulcers and strictures. CONCLUSIONS: RYGB and SG procedures stand out as effective bariatric surgical choices for treating obesity and T2DM. RYGB produces superior weight loss and metabolic outcomes, whereas SG presents a safer overall profile. The surgical selection process should be individualized on the basis of comorbidities, T2DM duration, and ongoing postoperative monitoring needs.