Roux-en-Y gastric bypass effective over sleeve gastrectomy for BMI loss among patients with obesity, finds study

A new study published in the Journal of American Medical Association focusing on Swiss Multicenter Bypass or Sleeve Study randomized clinical trial, Roux-en-Y gastric bypass, showed superiority over sleeve gastrectomy for patient excess body mass index decrease after more than 10 years of follow-up.

There are few reports on the long-term results of randomized clinical studies contrasting Roux-en-Y gastric bypass (RYGB) versus laparoscopic sleeve gastrectomy (SG). Thereby, to examine the long-term weight and metabolic results, reoperation rates, and quality of life of patients receiving SG vs RYGB after 10 years and beyond, Marko Kraljević and team carried out this study.

4 bariatric facilities in Switzerland participated in the randomized clinical study known as the Swiss Multicenter Bypass or Sleeve Study (SM-BOSS) between January 2007 and November 2011. In July 2023, the most recent follow-up was acquired. 217 individuals were recruited and randomly assigned to get SG or RYGB out of the 3971 patients with extreme obesity who were evaluated.

The primary interventional methods used in this investigation were laparoscopic SG or RYGB. The percentage excess body mass index decrease (%EBMIL) at 5 years was the main result of the SM-BOSS experiment. The current study provides information on long-term weight and metabolic outcomes after 10 years and beyond, including quality of life, reoperation rates, and changes in weight and obesity-related disorders.

A total of 156 patients (71.9%) were female, the mean (SD) age of the 217 patients randomly assigned to have SG or RYGB was 42.5 (11.1) years, and the mean (SD) baseline BMI was 43.9 (5.3). Out of 217 patients, 107 were randomly assigned to SG and 110 to RYGB. For 65.4% of patients, a full 10-year follow-up is available.

The mean (SD) percentage of EBMIL in the intention-to-treat group was 65.2% (26.0) following RYGB and 60.6% (25.9) following SG (P =.29). When compared to RYGB, patients who had SG had far greater conversion rates because to inadequate weight loss or reflux. After 10 years, the mean (SD) percentage EBMIL for patients receiving RYGB was substantially greater than that of SG in the per-protocol (PP) sample.

Also, there was no significant difference in the mean (SD) percentage of total weight reduction across the groups. De novo gastroesophageal reflux disease (GERD) was much more common in SG patients than in RYGB patients (P =.02). Overall, patients receiving SG had a considerably larger number of conversions to other architecture than those getting RYGB. 

Source:

Kraljević, M., Süsstrunk, J., Wölnerhanssen, B. K., Peters, T., Bueter, M., Gero, D., Schultes, B., Poljo, A., Schneider, R., & Peterli, R. (2025). Long-term outcomes of laparoscopic Roux-en-Y gastric bypass vs laparoscopic sleeve gastrectomy for obesity: The SM-BOSS randomized clinical trial. JAMA Surgery. https://doi.org/10.1001/jamasurg.2024.7052