OAGB is effective and safe conversional procedure after LSG

One anastomosis gastric bypass (OAGB) is an effective and safe conversional bariatric surgical procedure for insufficient weight loss and weight regain following sleeve gastrectomy (SG), according to researchers from the Iran University of Medical Sciences, Tehran, Iran. In addition, they investigators reported OAGB was associated with satisfactory changes in obesity associated medical problems with optimal weight loss results obtained at two-year follow-up. The findings were reported in the paper, ‘Five-year outcomes of one anastomosis gastric bypass as conversional surgery following sleeve gastrectomy for weight loss failure’, published in Scientific Reports.

The authors noted that unsatisfactory weight loss/regain, gastroesophageal reflux disease (GERD), stricture and food intolerance after SG can lead to conversion surgery in up to 25% of the patients. Therefore, they performed a study to evaluate the safety and five-year outcomes of OAGB following SG due to weight loss failure and weight regain.


Using data from the were collected from the Iranian National Obesity Surgery Database (INOSD) and all surgical procedures were performed at a tertiary, academic and accredited IFSO-EC bariatric surgery centre.


All the patients who had undergone OAGB from September 2014 to January 2017 were evaluated. In total, 1,356 patients had an OAGB, including 73 cases as conversion surgery with 29 patients having a conversional OAGB following SG due to weight regain or incomplete weight loss (SG ‘failure’ was defined as an unsatisfying weight loss (EWL<50% in one year), a BMI>35 kg/m2 after reaching the appropriate weight or 25% EWL increase from the nadir weight) with 23 patients completing five-year follow up.


The indication of conversion to OAGB was SG failure in all the cases, including 39% (n=9) for weight regain and 61% (n=14) for weight loss failure, and the mean age of the patients was 42.4 years and the majority (87.0%) were female.

At one-year follow-up, there were no major complications (defined as any complication that result in seven-day hospital stay), re-intervention or reoperation such as anastomotic leak requiring reoperation, venous thrombotic event (VTE) and gastrointestinal bleeding.


All the cases (100%) in this study had remission/improvement in DM, DLP, OSA, and HTN 1 year after their conversion surgery, but one case had DM recurrence at fvie-year follow-up. There were also three new-onset GERD symptoms with GERD-score more than eight at one-year follow-up after conversional OAGB with sign of bile reflux and esophagitis in EGD that two of them resolved in year two. However, one patient had persistent GERD symptoms at five-years and was on medication.


The repeated measurement analysis showed statistically significant (p<0.001) changes in the trend of BMI, which had reached its nadir year two after he surgery. Mean BMI before conversional surgery, at one, two, three and five-year follow-ups were 46.3±10.4, 34.5±8.5, 34.1±8.6, 35.7±8.7 and 37.5±11.6, respectively. Mean %EWL at one, two, three and five-year follow-ups were 51.6±11.0, 52.9±13.1, 45.5±16.4 and 41.0±18.0, respectively (Figure 1). Mean %TWL at one, two, three and five-year follow-ups were 26.6±5.9, 27.4±7.2, 23.9±9.2 and 20.9±9.3, respectively.

Figure 1: Trend of change in %EWL during 5 years after conversional OAGB through repeated measure test. %EWL percent excess weight loss.

“Despite the efficacy and safety of conversional OAGB, there is a concern around new-onset GERD,” the authors cautioned. “…Therefore, it can be concluded that OAGB has different effects on GERD, although some patients get symptom-free and most symptomatic patients will experience improvements by medication administration.”


Further information

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