Banded one-anastomosis gastric bypass shows 72.2% EWL at five years



The outcomes from a pilot study of patients with super-obesity (BMI≥50) has reported durable BMI loss of 25.9 kg/m2 (EWL 72.2%) at five years following banded one-anastomosis gastric bypass (B-OAGB) procedures. The study is believed to be the first to specifically study and report long-term outcomes in super-obese patients following the B-OAGB procedure.

The study, ‘5-Year Results of Banded One-Anastomosis Gastric Bypass: a Pilot Study in Super-Obese Patients’, published in Obesity Surgery, led by Dr Karl Miller, Salzburg, Austria, examined the long-term surgical outcomes, including of quality of life (QoL) and compared the results to the three common bariatric procedures (vertical banded gastroplasty (VBG), adjustable gastric banding (AGB) and Roux-en-Y gastric bypass (RYGB)) using the standardised Bariatric Reporting Outcomes System (BAROS).

The single centre included 12 patients who had a B-OAGB and evaluate the safety and effectiveness at six, 12, 24, 36, 48 and 60 months. The effectiveness criteria of the procedure included weight loss in terms of BMI, absolute weight, waist circumference, hip circumference, waist-to-hip ratio, percentage of total weight loss (TWL) and percentage of excess weight loss (EWL), and improvement/resolution of obesity-related comorbidities.

They explained that a standard OAGB was performed (as described by Garcia-CaballeroM, Carbajo M. One anastomosis gastric bypass: a simple, safe and efficient surgical procedure for treating morbid obesity. Nutr Hosp. 2004;19(6):372–5) and using the perigstric technique the MIDCAL nonadjustable ring (MID) was placed with a band length adjustment of 7.5–8 cm. The MIDCAL ring has four locking positions to adjust four sizes (circumferences of 65, 70, 75 and 80 mm) in order not to narrow the gastric pouch. The widest position of 80 mm was used in all patients.

“It is important not to place the ring too close to the esophagogastric junction, therefore we placed all the rings approximately 5 cm distal of the esophagogastric junction,” explained Dr Miller. “When calibrating the ring, it is also important to maintain a slim sleeve so there is no big pouch above the ring. The technique of placing the ring in B-OAGB is no different from banded-RYGB - the placement of the ring is between the blood vessels for the pouch but surgeons must ensure the ring does not affect the blood supply so remember not fit a ring that is too tight.”

Between October 2013 and February 2014, 12 patients (seven men, five women) underwent the B-OAGB procedure. The patients’ mean age was 38.2 ± 6.5 years (30.0– 50.0) and their mean pre-operative BMI was 57.5 ± 6.3 (range 50.5–72.6). All patients were available throughout the five years of follow-up. There were no perioperative complications, mortality, reoperation or readmission within 30 days of the procedure.

They authors reported that at 60 months, mean respective TWL was 45.3±7.5% and the mean EWL was 72.2 ± 12.8%, with no statistically significant difference between the genders. At the same time period, compared to baseline measures, statistically significant reductions in weight-related outcome measures were reported in relation to BMI mean change (25.9 ± 5.4, p<0.001), absolute weight mean change (76.1±16.4kg, p<0.001), waist circumference mean change (46.5±8.6cm, p<0.001). There were also statistically significant reductions in hip circumference (p<0.005) and waist-to- hip ratio (p<0.005).

Regarding comorbidities, T2DM remission and resolution of sleep apnoea occurred in all patients and there were statistically significant decreases in percentages of patients with associated metabolic markers, although there was no significant reduction in resting rate blood pressure among patients, but there was a trend towards it (p=0.08).

Between 11 and 24 months, three 12 patients had the ring removed due to stasis oesophagitis with recurrent vomiting, hypoalbuminemia and anaemia.

“I consider these removals as band related complications because they were the wrong patients to receive the procedure,” added Dr Miller. “Careful patient selection is mandatory including psychological counselling and it is super important to ascertain and understand the patients eating habits, and to provide the necessary post-procedural support.”

The study also found that overall QoL was also significantly improved by six months and at each follow-up time thereafter through to five years. Moreover, the composite BAROS score significantly increased at each time point and at final follow-up, 9/12 (75%) received a composite BAROS rating for surgical success ranging from very good to excellent.

The authors observed that B-OAGB BAROS subscale and composite scores compared favourably to those of VBG, AGB and RYGB, with the final B-OAGB composite score second to RYGB.

Of note, no patients reported symptoms of gastroesophageal reflux, although Dr Miller cautioned that although the researchers asked the patients, reflux was not in the study protocol.

“In the last meeting with Dr Mohit Bhandari from India, who has a great experience with banded procedures, he showed that his banded patients do not have reflux, maybe stasis but no reflux – this might be a great opportunity to research this issue and this needs to be investigated in future studies.”

Overall, the authors concluded that placing a ring during an OAGB in super-obese patients “may enhance and preserve excess weight loss over the long term, although further investigation with RCTs is needed as available observational studies are inconclusive.”

“The optimal procedure depends on many criteria and correct patient selection, for regular patients with BMI 40-50, I still prefer RYGB if appropriate,” he added. “However, we still do no know which patients will respond best to B-OAGB, maybe those patients who are big eaters. Additional studies need to be performed to examine the specifics of the procedure - such as higher band placement - and assess possible complications, in particular gastroesophageal reflux.”