Long-term Outcomes of RYGB vs SADI as Revision After Failed Sleeve Gastrectomy

Overview

This systematic review and meta-analysis compared the long-term efficacy of Roux-en-Y gastric bypass (RYGB) and single anastomosis duodeno-ileal bypass (SADI) as revisional surgeries following failed sleeve gastrectomy (SG). The analysis focused on outcomes with at least 5 years of follow-up, highlighting differences in weight loss, comorbidity resolution, and complication profiles.

Background

Sleeve gastrectomy (SG) is the most commonly performed bariatric procedure due to its relative simplicity, but it may result in insufficient long-term weight loss or severe gastro-esophageal reflux disease (GERD) in a significant subset of patients. Revisional bariatric surgery (RBS) is often required for these 'failed' SG cases, with Roux-en-Y gastric bypass (RYGB) and single anastomosis duodeno-ileal bypass (SADI) being common options. While RYGB is considered the gold standard, SADI has gained popularity due to promising weight loss outcomes and potentially fewer nutritional deficiencies, though long-term comparative data remain limited.

Data Highlights

The review included studies with a minimum follow-up of 5 years comparing RYGB and SADI after failed SG. Key parameters assessed were excess weight loss (EWL%), resolution of comorbidities such as type 2 diabetes mellitus (T2DM), and complication rates including GERD and nutritional deficiencies. The Newcastle-Ottawa scale was used to ensure study quality with a cut-off score of 5 points for inclusion.

Key Findings

• Both RYGB and SADI provide significant long-term weight loss after failed SG, with SADI showing a trend toward greater excess weight loss.
• SADI may offer superior resolution of obesity-related comorbidities, including type 2 diabetes mellitus, compared to RYGB.
• RYGB remains the preferred revisional procedure in patients with severe GERD due to its anti-reflux properties.
• SADI is associated with fewer nutritional deficiencies and complications than traditional biliopancreatic diversion with duodenal switch, but long-term safety data are still emerging.
• There is no universally accepted definition of 'failed' SG, but indications for revisional surgery generally include insufficient weight loss (EWL <50% or BMI >35 kg/m2) and complication-related issues such as GERD or stenosis.

Clinical Implications

Clinicians should consider patient-specific factors such as presence of GERD and severity of obesity when selecting revisional surgery after failed SG. RYGB remains the standard for patients with reflux symptoms, while SADI may be preferred for enhanced weight loss and metabolic improvement in appropriate candidates. Long-term monitoring for nutritional deficiencies is essential, especially following SADI.

Conclusion

Both RYGB and SADI are effective revisional procedures after failed sleeve gastrectomy, with SADI showing promising long-term weight loss and comorbidity resolution. Further large-scale, long-term studies are needed to fully establish the comparative safety and efficacy profiles of these procedures.

References

1. Lee et al. 2024 -- Systematic review comparing malabsorptive procedures with RYGB after failed SG
2. Chierici et al. 2024 -- Systematic review on SADI and one-anastomosis gastric bypass effectiveness
3. Mann et al. 2020 -- Defining indications for revisional bariatric surgery
4. Biron et al. 2019 -- Criteria for insufficient weight loss in severe obesity