Comparison of Single Versus Double Anastomosis Bariatric Metabolic Surgery in Obesity: a Systematic Review and Meta-analysis.

Major BMS are modified through loop rather than Roux-en-Y type reconstruction recently, and this study systematically reviews the BMS from the perspective of SA (single anastomosis) and DA (double anastomosis) procedures, aiming to research the differences among bariatric procedures. A total of 39 studies compared SA- and DA-BMS were finally eligible for analysis after searching in PubMed, Web of Science, and Cochrane Library. Compared with DA, SA shortens operative time and decreases complications especially obstruction, internal hernia, and reoperation. SA-GB (gastric bypass) has significantly higher %TWL and T2DM remission rate than DA-GB 1- and 5-year postoperatively. SA-DS (duodenal switch) has similar 1-year %TWL and lower 5-year %TWL, and comparable 1- and 5-year T2DM remission with DA-DS. SA provides significant advantages about simplicity and safety. This, together with the shorter learning curve, makes SA a promising choice.