Health Information

Study Finds Obesity 'Switch' Surgery More Effective

< Sep. 19, 2012 > -- Weight-loss surgery can help people who are severely obese shed the extra pounds, but one type of surgery seems to work better than others at keeping off the weight.

Researchers at Madigan Army Medical Center in Fort Lewis, Wash., compared the results of more than 77,000 people who had traditional gastric bypass surgery with more than 1,500 people who had an alternative procedure called duodenal switch. All of the people were obese or "super obese," with an average body mass index (BMI) of more than 48.

Doctors consider a person with a BMI of 30 or more to be obese. More than a third of Americans are obese.

Comparing procedures

Gastric bypass is considered the gold standard of obesity surgery. In it, the surgeon reduces the size of the stomach and bypasses the pyloric valve, which separates the stomach from the small intestine. In a duodenal switch, the surgeon leaves the pyloric valve intact. This prevents some complications linked with gastric bypass and allows for more normal digestion, which preserves vital nutrients.

Both types of surgery carry risks. The duodenal switch, for instance, takes about 20 minutes longer to do and requires a longer hospital stay. Nearly all of the traditional gastric bypass procedures in the study were done laparoscopically, but only about half of the duodenal switch procedures were laparoscopic. (The rest were open surgery.)

Laparoscopic surgery uses a laparoscope, a thin, flexible tube with a video camera inside. The surgeon places the laparoscope through a small cut in the abdomen. The camera takes images that the surgeon can see on a computer screen.

Although both types of surgery can lead to immediate, dramatic weight loss, people often struggle to maintain their new weight and over time regain some or many of the lost pounds.

Long-term benefits

In the current study, people who had the duodenal switch were better able to keep off that lost weight in the long term. This was especially noticeable among those who were the most obese. Two years after surgery, 79 percent of those who had a duodenal switch still had a significant weight loss, compared with 67 percent who had gastric bypass.

In addition, almost 20 percent of people who had a gastric bypass weren't able to lose least 50 percent of their body mass at the two-year follow-up, compared with 6 percent who underwent a duodenal switch.

And people who had a duodenal switch saw a greater improvement in obesity-related conditions: type 2 diabetes, high blood pressure, high cholesterol, and sleep apnea.

"Duodenal switch has superior weight loss and may be more appropriate as the primary bariatric operation in carefully selected patients," says Alec Beekley, M.D., at Thomas Jefferson University Hospitals in Philadelphia, who wrote an editorial accompanying the study.

The study was published this week in the Archives of Surgery.

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Duodenal Switch Surgery

The full name of this surgery is biliopancreatic diversion with duodenal switch. Your doctor may recommend this surgery if you have a body mass index (BMI) of 40 or greater or a BMI of 35 with serious health problems caused by your obesity. These health problems include:

Type 2 diabetes
Sleep apnea
High blood pressure
Heart disease
High cholesterol
Nonalcoholic fatty liver disease

Duodenal switch surgery is a complex procedure that tackles weight loss in three different ways. First, the surgery takes out a large portion of the stomach to stop you from overeating. With less stomach to fill, you will feel full more quickly and eat less food and fewer calories.

The second part of the procedure reroutes food away from the small intestine, which is the natural path of digestion. This cuts back on how many calories and nutrients your body is able to absorb.

The third part of the procedure changes the normal way that bile and digestive juices break down food. This cuts back on how many calories you absorb, causing still more weight loss.

Always talk with your health care provider for more information.