SEATTLE—Bypass resulted in much greater weight loss and fewer reoperations than did banding, according to a large national study in JAMA Surgery comparing two of the gastric surgery procedures that are done most commonly for obesity. But bypass was linked to more risk of short-term complications than was banding. The study report is called "Comparative effectiveness of laparoscopic adjustable gastric banding versus laparoscopic gastric bypass in 10 health systems."
"This is important because more and more people are living with severe obesity and having bariatric surgery," said David Arterburn, MD, MPH, an associate investigator at Group Health Research Institute, a Group Health physician, and an affiliate associate professor of medicine at the University of Washington School of Medicine. "They need to know what the potential pros and cons are—so they can have informed discussions with their doctors about which course suits them best, based on what matters most to them as individuals."
The study included nearly 7,500 patients from 10 U.S. health care systems who had laparoscopic bariatric surgery 2005–2009 and were followed up through 2010. The health systems took part in the study through their collaboration in two research networks: the Scalable PArtnering Network for Comparative Effectiveness Research: Across Lifespan, Conditions, and Settings (SPAN) and HMO Research Network.
Patients were more likely to experience at least one major complication within 30 days afterward if they had bypass (3 percent) than if they had banding (1.3 percent). These short-term complications included blood clots in veins, not being discharged from the hospital, and even death.
"But major short-term complications were relatively rare, even with bypass—and they are becoming even less common over time," Dr. Arterburn said.
Dr. Arterburn is an associate investigator at Group Health Research Institute, a Group Health physician, and an affiliate associate professor of medicine at the University of Washington School of Medicine, in Seattle.
(Photo Credit: Group Health Research Institute)
On average, patients lost nearly 7.0 more body mass index (BMI) points with bypass (14.8) than with banding (8.0). With longer-term follow-up (2.3–6 years), bypass patients were less likely to be operated on again (5.5 percent, versus 13.7 percent for banding patients).
"The optimal bariatric procedure would result in the greatest weight loss and long-term weight loss maintenance with the least risk of short- and long-term problems," Dr. Arterburn added. "Instead, we found tradeoffs between these two common procedures."
Currently, Roux-en-Y gastric bypass accounts for 47 percent—and adjustable gastric banding accounts for 18 percent—of bariatric procedures worldwide. Unlike bypass, banding is reversible—and often reversed, sometimes because of discomfort or failure to lose enough weight. The study didn't include another type of bariatric surgery, called sleeve gastrectomy, which accounts for 28 percent of bariatric procedures. Dr. Arterburn recently discussed in JAMA and The BMJ how well bariatric surgery works.
"We need to compare the longer-term outcomes of various types of this surgery, including maintaining weight loss," Dr. Arterburn said. "Several sites from our group are now looking at the impact of bariatric surgery on the long-term risk of cancer and complications from diabetes."
Source: Group Health Research Institute