Ten-Year Outcomes of Single-Anastomosis Sleeve Ileal (SASI) Bypass: Surgical Configuration Determines Long-Term Efficacy and Safety

INTRODUCTION: The metabolic foundation of Single Anastomosis Sleeve Ileal (SASI) bypass is based on the combination of sleeve gastrectomy with a loop gastroileal bypass. The short- and mid-term outcomes were reported in favor of adequate weight loss and safe nutritional profile. The long-term efficacy and safety remain uncertain, particularly regarding optimal limb length and anastomosis size. METHODS: A retrospective cohort study of patients who underwent SASI bypass between 2013 and 2014. Three groups based on the surgical technique: Group1: 2.5 m ileum, 4-6 cm anastomosis, Group2: 3.0 m ileum, 2.5 cm anastomosis, and Group3: 3.5 m ileum, 2.5 cm anastomosis. The primary outcome included weight loss, diabetic remission, and nutritional deficiencies requiring intervention. RESULTS: Ninety-five patients were eligible with 10-year follow-up data available for 89 (93.7%). The mean percentage of excess weight loss (%EWL) was 58.6 ± 20.3%. Diabetic remission was sustained in 88%. Group1 had a 60% malnutrition rate and 40% reversal rate. Group2 and group3 showed significantly fewer nutritional complications, with no surgical revisions in Group 3. In this group, all diabetic patients remained in complete remission at 10 years. Weight outcomes between Groups 2 and 3 were comparable, though Group 3 had a slightly higher mean %EWL at 10 years (62.5% vs. 57.0%; p = 0.21). CONCLUSION: SASI bypass offers durable long-term weight loss and diabetic remission rates at 10 years. Outcomes are highly dependent on surgical technique. The current data suggests the optimal outcome is offered with the 3.5 ileum/ 2.5 cm anastomosis configuration. Standardization of technique is critical to ensure long-term efficacy and safety.