The effect of Roux-en-Y gastric bypass compared with omega-loop gastric bypass on weight loss, perioperative surgical events, and comorbidities.

Background: In comparison to conservative therapy, bariatric surgery has shown many reasonable results. The current study investigates whether Omega-loop-gastric-bypass (OAGB) or Roux-en-Y gastric-bypass (RYGB) improves weight loss, comorbidities, and perioperative complications.

Methods: The study included 28,683 patients after RYGB and OAGB. Outcome criteria were perioperative morbidity, perioperative complications, and remission of comorbidities after one year of follow-up.

Results: Of them 14,253 patients had completed a one-year follow-up (13,483 patients by RYGB and 770 by OAGB). BMI reduction was a significant difference in favor of OAGB (17.5±5.6 kg/m for OAGB vs. 15.2±5.0 for RYGB; P<0.001). The %EWL was not significantly different between the two groups (P=0.073). There was also no significant difference in perioperative complications between the two groups (overall P>5%). Significant differences in favor of OAGB were observed in remission of insulin-dependent diabetes mellitus (IDDM) (P<0.001), and sleep apnea (P=0.002). Remission of reflux was more observed in RYGB than OAGB (P<0.001). Operating time was significantly higher in RYGB than OAGB (P<0.001).

Conclusions: Compared with RYGB, OAGB showed significant advantages in many respects. In particular, remission of comorbidities was significantly better after OAGB than in patients after RYGB during the one-year follow-up period. Nevertheless, many other factors such as medical history, long-term expected goals of bariatric surgery, and preexisting comorbidities should be taken into account when determining indications between the two procedures. Further studies with longer follow-up periods should be conducted to determine the efficacy of the two methods more accurately.