One anastomosis gastric bypass (OAGB) is an ASMBS-endorsed bariatric surgery. As utilization of OAGB increases, it is important that the safety profile of OAGB be rigorously assessed. We therefore aimed to study the 30-day safety of OAGB compared to a similar gastro-jejunal anastomotic procedure, Roux-en-Y gastric bypass (RYGB).


A matched case-control study was conducted of patients (Age 13-80) who underwent primary gastric bypass surgery 2021-2022, identified in the MBSAQIP database. Each patient who underwent OAGB was matched to 4 controls who underwent RYGB on age (+/-10), sex, race, body mass index (+/- 5 kg/m2), preoperative functional status, American Society of Anesthesia (ASA) classification, and 13 comorbidities. Univariate, multilevel and multivariate regression analyses were performed.


1569 patients who underwent OAGB were matched to 6276 controls. Matched baseline characteristics were similar between groups. Operative time, length of stay (LOS), and overall complication rate were lower in the OAGB cohort (p<0.001, Table), despite higher 30-day BMI loss percentage (p=0.048). OAGB was associated with a significantly lower bowel obstruction rate, as compared to RYGB (0.1% vs 1.0%, p<0.001). On logistic regression adjusting for all variables used in matching, OAGB was associated with a 27% decrease in overall complication rate (OR 0.73, 95% CI 0.62-0.87, p<0.001) (Image).


Although OAGB is minimally utilized, the 30-day safety profile appears favorable. As compared to RYGB, OAGB was associated with shorter operative time, shorter LOS, and a lower complication rate, partially due to minimization of small bowel obstructions with a loop anatomy.