Sleeve Gastrectomy, One-Anastomosis Gastric Bypass (OAGB), and Single Anastomosis Sleeve Ileal (SASI) Bypass in Treatment of Morbid Obesity: a Retrospective Cohort Study

Purpose: Bariatric surgery is the most effective treatment for morbid obesity. The present study aimed to assess three bariatric procedures with different mechanisms of actions; sleeve gastrectomy (SG), one-anastomosis gastric bypass (OAGB), and single anastomosis sleeve ileal (SASI) bypass, in terms of efficacy and safety. Methods: This was a retrospective cohort study on patients with morbid obesity who underwent SG, OAGB, or SASI bypass. The main outcome measures were weight loss and improvement in comorbidities at 6 and 12 months postoperatively, and complications. Results: A total of 264 patients (186 female) with mean preoperative body mass index (BMI) of 43.6 ± 9.9 kg/m²were included to the study. Significant weight loss was recorded at 6 and 12 months after the three procedures. At 6 and 12 months postoperatively, body weight and BMI were significantly lower after SASI bypass than after SG and OAGB. The %total weight loss (%TWL) and %excess weight loss (%EWL) were significantly higher after SASI bypass than after SG and OAGB. SASI bypass was associated with a significantly higher rate of improvement in DM than SG and OAGB (97.7% vs 71.4% vs 86.7%; p = 0.04) whereas improvement in other comorbidities was similar. The short-term complication rate was similar between the three procedures, yet SASI bypass was followed by higher long-term complication rate. Conclusion: Based on retrospective review of data, SASI bypass was associated with more reduction in body weight and BMI, higher %TWL and %EWL, better improvement in T2DM, and more long-term nutritional complications than SG and OAGB.