Laparoscopic Roux-Y-gastric bypass versus laparoscopic one-anastomosis gastric bypass for obesity: clinical & metabolic results of a prospective randomized controlled trial

One anastomosis gastric bypass (OAGB) has been proposed as an effective alternative to the current standard procedure in Switzerland, Roux-en-Y gastric bypass (RYGB). Prospective data comparing both procedures are scarce. Therefore, we performed a non-inferiority randomized controlled trial assessing the effectiveness and safety of these 2 operative techniques.

Eighty patients were randomized 1:1. OAGB consisted of a very long gastric pouch with a 200 cm biliopancreatic limb, RYGB of a 150 cm ante-colic alimentary and a 60 cm biliopancreatic limb, respectively. Primary endpoint was the percent excess weight loss (%EWL) at 12 months after surgery.

Mean %EWL at 12 months was 87.9% (SD24.4) in the RYGB group and 104.1% (SD24.6) in the OAGB group (p = 0.006). There was no mortality. The rate of marginal ulcers was higher in patients with OAGB compared to those with RYGB (p = 0.011), while the total number of late complications did not statistically differ between the two groups. Except for the remission of GERD, which was higher in the RYGB group compared to OAGB, there was no difference between the groups regarding the remission of comorbidities. OAGB showed improved glucose control compared to the RYGB after 1 year (p = 0.001). Furthermore, glucagon-like peptide-1 increase was significantly higher in OAGB at 6 weeks (p = 0.041) and 1 year after surgery (p = 0.029). Quality of life improved after both surgeries, without differences between the groups.

%EWL 1 year after surgery was higher in OAGB than in RYGB. A better glycemic control with a higher increase in GLP-1 was observed after OAGB compared to RYGB.

Trial registration: This trial is registered on ClinicalTrials.gov under the identifier NCT02601092.