A decade-long follow-up of the Swiss Multicenter Bypass or Sleeve Study randomized clinical trial found that Roux-en-Y gastric bypass resulted in greater excess body mass index loss than laparoscopic sleeve gastrectomy, with patients experiencing higher conversion rates due to gastroesophageal reflux disease and insufficient weight loss.
The trial enrolled 217 patients with severe obesity between 2007 and 2011 across 4 bariatric centers. Patients were randomized to undergo sleeve gastrectomy or Roux-en-Y gastric bypass (RYGB), with weight loss and metabolic outcomes assessed over 10 years, according to study results published in JAMA Surgery.
Follow-up data were available for 65.4% of participants. In the intention-to-treat analysis, mean percent excess body mass index loss (%EBMIL) at 10 years was 60.6% (standard deviation [SD] 25.9) after sleeve gastrectomy and 65.2% (SD 26.0) after RYGB.
Per-protocol analysis—which included only patients who completed the entire study period without conversion to another procedure—showed significantly higher %EBMIL for RYGB compared to sleeve gastrectomy (65.9% versus 56.1%, respectively). Total weight loss percentage was similar between groups (RYGB 27.7% versus sleeve gastrectomy 25.5%).
Sleeve gastrectomy patients had significantly higher conversion rates due to inadequate weight loss or GERD, with a conversion rate of 29.9% compared to 5.5% in the RYGB group. Of the 32 sleeve gastrectomy patients receiving reoperation, 1 (3.1%) received a resleeve, 5 (15.6%) were converted to biliopancreatic diversion with duodenal switch, and 26 (81.3%) were converted to RYGB.
De novo GERD developed in 32.3% of sleeve gastrectomy patients versus 7.9% of RYGB patients, though it's worth noting that approximately 68% of sleeve gastrectomy patients and 72% of RYGB patients with existing GERD at baseline experienced remission after surgery.
Both procedures resulted in substantial improvements in obesity-related comorbidities, including type 2 diabetes (T2D), dyslipidemia, and hypertension. At baseline, 26.1% of sleeve gastrectomy patients and 19.2% of RYGB patients had T2D.
After 10 years, complete T2D remission was observed in 61.1% of sleeve gastrectomy patients and 71.4% of RYGB patients. Dyslipidemia remission rates were 31% for sleeve gastrectomy and 19.4% for RYGB, while hypertension remission rates were 52.5% and 48.8%, respectively. Obstructive sleep apnea improved in 93.8% of Sleeve gastrectomy patients and 71.9% of RYGB patients, though this difference was not statistically significant.
All-cause mortality rates were 0.9% for sleeve gastrectomy and 4.5% for RYGB, while procedure-related mortality was 0% for sleeve gastrectomy and 0.9% for RYGB. Only 5.5% of RYGB patients required revision surgery, all for inadequate weight loss.
Quality of life, assessed using the Moorehead-Ardelt Bariatric Analysis and Reporting Outcome System (BAROS), improved significantly for both groups with no statistically significant differences.
These results align with the SLEEVEPASS trial, which also reported better weight loss outcomes with RYGB, though differences did not meet pre-specified equivalence margins. The findings are particularly relevant considering that sleeve gastrectomy became the most commonly performed bariatric procedure worldwide in 2014, surpassing RYGB. It should be noted that patients with severe GERD were excluded from the study, which might impact the generalizability of findings.
Full disclosures are detailed in the study.
