Obesity Surgery

, Volume 28, Issue 9, pp 2956–2967 | Cite as

One Anastomosis (Mini) Gastric Bypass Is Now an Established Bariatric Procedure: a Systematic Review of 12,807 Patients

  • Chetan D. ParmarEmail author
  • Kamal K. Mahawar
Review Article


The One Anastomosis (Mini) Gastric Bypass is rapidly gaining acceptance. This review reports cumulative results of 12,807 procedures in obese patients with a mean age of 41.18 years and BMI of 46.6 kg/m2. The overall mortality was 0.10% and the leak rate was 0.96%. The follow-up duration ranged from 6 months to 12 years. A marginal ulceration rate of 2.7% and an anaemia rate of 7.0% were reported. Approximately 2.0% of patients reported postoperative gastro-oesophageal reflux and 0.71% developed malnutrition. Excess weight loss at 6, 12, 24 and 60 months was 60.68, 72.56, 78.2 and 76.6% respectively. Type 2 diabetes mellitus and hypertension resolved in 83.7 and 66.94% respectively. We conclude that there is now sufficient evidence to include MGB-OAGB as a mainstream bariatric procedure.


Bariatric surgery Gastric bypass One anastomosis gastric bypass Mini gastric bypass Single anastomosis gastric bypass Omega loop gastric bypass Loop gastric bypass 



One Anastomosis (Mini) Gastric Bypass


Preferred Reporting Items for Systematic Reviews and Meta-Analyses


excess weight loss


randomised controlled trial


Roux-en-Y gastric bypass


laparoscopic adjustable gastric banding


sleeve gastrectomy


gastro-oesophageal reflux disease


iron deficiency anaemia



Harriet Croxton, Librarian, Whittington Hospital.

Author Contributions

KM conceived the idea for the topic. KM and CP participated in literature search. CP collected most of the data and analysed it. CP and KM both contributed to manuscript writing. Both authors have seen the final version and approve of it.

Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interest.

Ethical Approval

For this type of study, ethical approval is not required.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.The Whittington HospitalLondonUK
  2. 2.Sunderland Royal HospitalSunderlandUK

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