Two-Year Weight Loss Outcomes After Sleeve Gastrectomy and Roux-en-Y Gastric Bypass in a Standardized Multidisciplinary Program: A Comparative Study

Introduction Adherence to multidisciplinary follow-up is considered an important determinant of long-term weight loss after metabolic and bariatric surgery (MBS). In addition, structured preoperative assessment and appropriate selection of surgical technique may influence postoperative outcomes and partly explain differences reported between procedures such as laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en-Y gastric bypass (LRYGB). Objective To compare 24-month weight outcomes in patients undergoing LSG and LRYGB within a standardized preoperative and multidisciplinary follow-up framework. Methods A retrospective comparative cohort study was conducted, including patients who underwent MBS between January 2021 and December 2023. Outcomes included percentage of total weight loss (%TWL), percentage of excess weight loss (%EWL), insufficient weight loss (%TWL <20%), and weight regain at six, 12, 18, and 24 months. Results A total of 71 patients were included (LSG: n=45 (63.4%); LRYGB: n=26 (36.6%)). Baseline characteristics were comparable between groups. At 24 months, no significant differences were observed between LSG and LRYGB in %TWL (29.9% vs. 30.8%) or %EWL (61.6% vs. 63.4%) (p>0.05). Insufficient weight loss, defined as %TWL <20%, decreased from 21.1% at six months to 9.9% at 12 months. Weight regain at 24 months was observed in 25.4% of patients, without significant differences between procedures. No baseline variable included in the model showed a statistically significant association with weight-loss success. Conclusions In a clinical setting characterized by standardized preoperative selection and strict multidisciplinary follow-up, LSG and LRYGB showed no statistically significant differences in the 24-month weight-loss outcomes. These findings suggest that patient selection, multidisciplinary follow-up, and institutional factors may contribute to the observed results, although their relative impact requires further investigation.