Gastric Bypass Surgery Better than Banding for Long-Term Health Outcomes
The two most common bariatric surgery procedures performed in the United States are the laparoscopic Roux-en-Y Gastric Bypass and the laparoscopic Adjustable Gastric Band. Both surgeries have benefits and risks, but two studies published in this month’s issue of the Archives of Surgery have found that gastric bypass surpasses gastric banding for long-term health outcomes, including greater weight loss, resolution of diabetes, and improved quality of life.
Gastric Bypass Superior to Banding and Sleeve Gastrectomy in Two Studies
To arrive at the findings, Dr. Guilherme M. Campos and colleagues at the University of California San Francisco examined 100 morbidly obese patients (BMI greater than 40) who had undergone gastric banding surgery with Allergan’s trademarked product, the Lap-Band. The patients were compared to 100 patients, matched by age, race, sex, and initial BMI, who had gastric bypass surgery. One year outcomes were available for 93 patients in the banding group and 92 in the gastric bypass group.
Average excess weight loss at one year for the gastric bypass patients was 64%, compared to 36% for those who had Lap-Band surgery. Additionally, 86 patients in the gastric bypass group successfully lost more than 40% of their excess weight, compared with 29 of the banding patients.
Each group had 34 patients with type 2 diabetes mellitus, a common co-morbidity to obesity. Resolution or improvement of diabetes was significantly better after gastric bypass as compared to Lap-Band. Seventy-five percent of gastric bypass patients were able to discontinue insulin use.
Quality of life was assessed using two resources. On the Bariatric Analysis and Reporting Outcome System, scores for quality of life averaged 5.7 with bypass surgery versus 3.6 in Lap-Band patients. Of the five domains in the Moorehead-Ardelt Quality of Life Questionnaire II, all showed higher values for the gastric bypass group.
While overall risk is greater for gastric bypass surgery, the rate of patients experiencing complications in this study was similar for both groups. Earlier complications (within 30 days post-surgery) were higher for gastric bypass patients, but reoperation rate was higher in Lap-Band patients. Complications included infection, internal bleeding and blood clots, but no deaths.
The authors conclude that “Because it achieves greater weight loss, increased resolution of diabetes, and better improvement in quality of life…in the setting we studied (high-volume centers with expert surgeons), laparoscopic Roux-en-Y gastric bypass has a better risk-benefit profile than laparoscopic adjustable gastric band.”
A second study compared the gastric bypass to the sleeve gastrectomy, another surgical weight loss procedure which reduces the stomach to about 20% of its original size. Because the sleeve gastrectomy is a newer bariatric procedure, there is less long-term data on its effectiveness.
Dr. Wei-Jei Lee of the Min-Sheng General Hospital in Taiwan and colleagues studied 60 moderately obese patients between the ages of 30 and 60, all of whom had poorly controlled type 2 diabetes after conventional treatment. Although weight loss surgeries in the United States are not approved for BMI lower than 30, the patients in this study all had BMI’s between 25 and 35 (mean 30.3).
About half of the patients were randomized to undergo gastric bypass surgery with duodenum exclusion, which means bypassing the first 12 inches of the small intestine. This surgery is different from the standard Roux-en-Y gastric bypass and tested the theory that eliminating passage of nutrients through the duodenum and jejunum alters metabolic signaling to normalize blood glucose levels. The other half of the participants had sleeve gastrectomy which removes a large portion of the stomach, but leaves the duodenum intact.
Both groups achieved significant weight loss in the early stages after surgery (at one and three-month post surgery follow up), but in the long-term, those having gastric bypass had better weight loss after six-months to one year.
Overall, 70% of patients had remission of type 2 diabetes one year after surgery. The resolution was significantly greater, however, for gastric bypass patients – 93% had resolved type 2 diabetes versus 47% of those having the sleeve gastrectomy. The gastric bypass patients also had lower blood lipid levels than those having the sleeve.
Complication rate was similar for both groups in the study, with each group having one late complication that required hospitalization for treatment.
The authors estimated that duodenal exclusion "may contribute to a 30% role in the mechanism of diabetes mellitus resolution after gastric bypass," with the other potential mechanisms accounting for 70%.
"Although more clinical trials are needed, this study and other previous studies have strongly recommended that laparoscopic gastric bypass as a metabolic surgery should be included in the armament of diabetes mellitus treatments in less obese populations (BMI of 25-35) and in the morbidly obese population (BMI greater than 35)," they conclude.
(Arch Surg. 2011;146:143-148, 149-155.