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Meta-Analysis
. 2025 Apr;35(4):1438-1446.
doi: 10.1007/s11695-025-07776-x. Epub 2025 Mar 14.

One Anastomosis Gastric Bypass Versus Roux‑en‑Y Gastric Bypass for Obesity: An Updated Meta‑analysis and Systematic Review of Randomized Controlled Trials

Yusuf Ahmed  1 , Karim Ataya  2 , Abdulla Almubarak  3 , Isa Almubarak  4 , Manar Ali  3 , Walaa Yusuf  5 , Mostafa Mohammed Saad Mahran  6 , Stefan Simeonovski  7 , Almoutuz Aljaafreh  8 , Wah Yang  9
Affiliations
Meta-Analysis

One Anastomosis Gastric Bypass Versus Roux‑en‑Y Gastric Bypass for Obesity: An Updated Meta‑analysis and Systematic Review of Randomized Controlled Trials

Yusuf Ahmed et al. Obes Surg. 2025 Apr.

Abstract

Background: Roux-en-Y gastric bypass (RYGB) is widely regarded as a cornerstone intervention for individuals afflicted with metabolic syndromes and severe obesity. However, one anastomosis gastric bypass (OAGB) emerged after RYGB as a more straightforward and less technically demanding operation. This systematic review and meta-analysis aims to compare both procedures and update the currently existing evidence.

Methods: We systematically searched PubMed, Scopus, and the Cochrane Central Register for randomized controlled trials (RCTs) that compared OAGB with RYGB as primary operations.

Results: Twelve studies were included in this meta-analysis, with a total of 904 patients. Total weight loss percentage (TWL%) was statistically higher in the OAGB group at 6 months (95% CI 0.80 to 2.94; P = 0.006) with no differences in 12, 24, and 36 months compared to RYGB. On the other hand, OAGB exhibited a significantly higher excess weight loss percentage (EWL%) compared to RYGB at 12 months (95% CI 3.08 to 9.73; P = 0.0002). EWL% was comparable in both procedures at 6, 24, and 60 months of follow-up. There were no statistically significant differences in terms of the resolution of comorbidities related to obesity. De novo gastro-esophageal reflux disease (GERD) (RR 2.58; 95% CI 1.55 to 4.3; P = 0.0003) and marginal ulcers (RR 2.7; 95% CI 1.07 to 6.84; P = 0.04) were significantly higher in patients who underwent OAGB in comparison to RYGB.

Conclusions: In conclusion, OAGB is comparable to RYGB in terms of weight loss parameters and comorbidity resolution. However, OAGB can lead to a higher risk of development of marginal ulcers and de novo GERD.

Keywords: One anastomosis gastric bypass; Roux-en-Y gastric bypass; Weight loss.

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Conflict of interest statement

Declarations. Statement of Ethics and Consent: This meta-analysis paper is based on previously published studies and does not involve any direct participation of human or animal subjects, and for this type of study, formal consent is not required. Competing Interests: The authors declare no competing interests.

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