One thousand single anastomosis (omega loop) gastric bypasses to treat morbid obesity in a 7-year period: outcomes show few complications and good efficacy.

BACKGROUND: A short-term randomized controlled trial shows that the one anastomosis gastric bypass (OAGB) is a safe and effective alternative to the Roux-en-Y gastric bypass (RYGB).

OBJECTIVE: The aim of this study is to evaluate the OAGB at our University Hospital between 2006 and 2013.

PATIENTS: One thousand patients have undergone an OAGB. Data were collected on all consecutive patients. The mean follow-up period was 31 months (SD, 26.3; range, 12-82.9), and complete follow-up was available in 126 of 175 patients (72 %) at 5 years after surgery.

RESULTS: Mortality rate was 0.2 %. Overall morbidity was 5.5 %; 34 required reoperations: i.e., 6 leaks, 5 obstructions, 5 incisional hernias, 7 biliary refluxes, 2 perforated ulcers, 2 bleeds, 2 abscesses, and 1 anastomotic stricture. Four patients were reoperated for weight regain. Overall rate of marginal ulcers was 2 % (n = 20), all in heavy smokers. Conversion from an OAGB to a RYGB was required in nine cases (0.9 %): seven for intractable biliary reflux, two for a marginal ulcer. At 5 years, percent excess body mass index loss was 71.6 ± 27 %. One hundred patients with type-2 diabetes, with a mean preoperative HbA1C of 7.7 ± 1.9 %, were followed for >2 years; the total resolution rate was 85.7 %.

CONCLUSION: This study confirms that the OAGB is an effective procedure for morbid obesity with comparable outcomes to RYGB; in addition, it seems to be safer with lower morbidity. Its technical simplicity represents a real advantage and makes it an option that should be considered by all bariatric surgeons.