One anastomosis gastric bypass vs. Roux-en-Y gastric bypass, remedy for insufficient weight loss and weight regain after failed restrictive bariatric surgery

BACKGROUND: Failure occurs in up to 60% of the patients that were treated with primary restrictive bariatric operations such as Laparoscopic Adjustable Gastric Banding (LAGB), or restrictive/metabolic operations like Laparoscopic Sleeve Gastrectomy (LSG). Insufficient weight loss and weight regain are the most commonly reported reasons of failure. The aim of this retrospective multicenter study was to compare One Anastomosis Gastric Bypass (OAGB) to Roux-en-Y Gastric Bypass (RYGB) as a revisional procedure in terms of weight loss, procedure time, complication rate and morbidity. METHODS: 491 patients operated on between 2012 and 2017 for failed restrictive surgery were included in this study (OAGB (n=185) or RYGB (n=306)). Failure was defined as total weight loss (TWL) less than 25%, excess weight loss (EWL) less than 50% and/or a remaining body mass index (BMI) larger than 40 kg/m2 at two years of follow up. Primary outcome measures were %TWL and % excess BMI loss (EBMIL) at 12, 24 and 36 months of follow-up. Secondary outcomes were procedure time, reduction of comorbidity, early and late complication rate, and mortality. RESULTS: %TWL was significantly larger in the OAGB group at 12 months (mean 24.1±9.8 vs. 21.9±9.7, p = 0.023) and 24 months (mean 23.9±11.7 vs. 20.5±11.2, p = 0.023) of follow-up. %EBMIL was significantly larger in the OAGB group at 12 months (mean 69.0±44.6 vs. 60.0±30.1, p = 0.014) and 24 months (mean 68.6±51.6 vs. 56.4±35.4, p = 0.025) of follow-up. Intra-abdominal complications (leakage, bleeding, intra-abdominal abscess and perforation) occurred less frequently after revisional OAGB (1.1% vs. 4.9%, p = 0.025). Surgical intervention for biliary reflux (5.4% vs. 0.3%, p < 0.001) was more prevalent in the OAGB group. Surgical intervention for internal herniation (0.0% vs. 4.9%, p = 0.002) was more prevalent in the RYGB group. CONCLUSIONS: This study suggests that OAGB is superior to RYGB as a remedy for insufficient weight loss and weight regain after failed restrictive surgery with more weight loss and a lower early complication rate. To substantiate these findings, further research from prospective randomized controlled trials is needed.