Comparative seven year outcomes of RYGB and SADI-S as revisional procedures for weight recurrence regain after sleeve gastrectomy: weight loss trajectory, reflux control, and metabolic safety

BACKGROUND: Sleeve gastrectomy (SG) is widely performed, yet 20-50% of patients experience insufficient weight loss or weight regain, leading to revisional surgery. Roux-en-Y gastric bypass (RYGB) and single-anastomosis duodeno-ileal bypass (SADI-S) are two commonly used revisional procedures, but long-term comparative data remain limited. This study evaluates 7-year outcomes of RYGB versus SADI-S as revisional surgeries for weight recurrence after SG. METHODS: A retrospective analysis was conducted on all adults undergoing revisional RYGB or SADI-S between 2014 and 2015 after inadequate weight loss or weight recurrence post-SG. Demographic, anthropometric, biochemical, and comorbidity-related variables were assessed at baseline, 1, 5, and 7 years. Statistical analyses included t-tests, chi-square tests, Kaplan-Meier curves, and multivariate regression (significance set at p < 0.05). RESULTS: The cohort included 105 patients (RYGB = 62; SADI-S = 43). SADI-S patients had higher baseline and pre-revision BMI. Across all follow-up points, SADI-S achieved significantly greater %TWL, %EWL, and BMI reduction, demonstrating superior long-term weight-loss durability. RYGB yielded markedly better GERD resolution (95 vs. 5%, p = 0.02), while remission of diabetes, hypertension, dyslipidemia, and asthma was similar between groups. Nutritional profiles differed: SADI-S was associated with lower calcium, zinc, folate, and vitamin D levels, whereas RYGB patients had lower vitamin B12. Overall complication rates, including bleeding, marginal ulcer, internal hernia, dumping syndrome, severe malnutrition, and iron-deficiency anemia, were not statistically significant. CONCLUSIONS: Both RYGB and SADI-S are effective and safe revisional options after SG. SADI-S offers superior long-term weight-loss and metabolic outcomes, whereas RYGB remains preferable for patients with significant or persistent GERD. Tailoring revisional procedure selection to patient characteristics and ensuring lifelong nutritional monitoring are essential for optimizing long-term outcomes.