点击显示 收起
Feb. 9, 2010 -- Gastric banding surgery produces substantially more weight loss in obese teens than medical treatment stressing lifestyle changes only, according to a new study.
The surgery group lost 76.2 pounds on average, while the lifestyle intervention group lost 6.6 pounds over the two-year study. Put another way, 84% of the gastric banding group lost more than 50% of their excess weight, but just 12% of those in the lifestyle intervention group did, says senior study author Paul E. O'Brien, MD, director of the Centre for Obesity Research and Education (CORE) at Monash University in Melbourne, Australia.
''It is highly successful," O'Brien tells WebMD of the results for surgery, explaining that a loss greater than 50% is viewed as good by weight loss surgeons.
Other weight loss experts say the study is one of the first to compare obesity surgery with lifestyle treatment in teens. More than 17.4%, or 5 million, U.S. teens are obese.
The study is published in the Journal of the American Medical Association.
Is Weight Loss Surgery Right for You? Take the Health Check
O'Brien and his colleagues randomly assigned 50 Australian teens, aged 14 to 18, with a body mass index (BMI) greater than 35 either to the lifestyle intervention or gastric banding and followed them for two years.
A BMI of 30 and above is considered obese. Participants also had obesity-related medical complications such as high blood pressure, asthma, back pain, physical disability, or psychosocial problems such as low self-esteem.
O'Brien's team used the gastric band known as Lap-Band. In the procedure, a hollow silicone band is placed around the upper part of the stomach, creating a small pouch capable of holding just a small amount of food.
Monash's Centre for Obesity Research and Education receives an unrestricted research grant from Allergan, Lap-Band's manufacturer. In the U.S., Lap-Band is approved for use in severely obese adults; its use in teens is under study.
Lifestyle intervention is always tried first for obesity treatment, and if that fails, surgery may be considered. In the study's lifestyle intervention group, the teens were instructed to reduce calorie intake (to about 800 to 2,000 calories a day, depending on their weight and age) and increase activity, with a target of more than 10,000 steps a day on the pedometer and at least 30 minutes a day of physical activity.
TV and other screen time was limited to two hours a day, and a personal trainer was provided to each teen for a six-week period. Parents were involved in the lifestyle intervention and education.
The gastric banding group had the procedure done within a month of being assigned to the group. They got detailed instructions on correct eating -- for instance, having three or fewer small meals a day, eating slowly, and chewing well. They were urged to get 30 minutes or more of formal exercise every day and to keep active during the day.
Twenty-four of the 25 teens in the surgery group and 18 of the 25 in the lifestyle group finished the study. Other results:
For several reasons, the banding type of bariatric surgery is preferred over other procedures, such as gastric bypass surgery, O'Brien says. "It is gentle, safe, effective, and fully reversible," he says. "A 15-year-old will be 35 in 20 years' time. Surely we will have better ways to control weight by then. If he has a [gastric band] he can have it out, all goes back to normal, and, if needed, he can go on the new therapy. That cannot happen with procedures that create major and essentially irreversible change [such as bypass surgery]."
As good as the results were, the researchers note in their report that the surgery "is not a quick fix." In fact, 28% of teens in the surgery group needed revisions because of enlargement of the stomach or other factors. To avoid the enlargement problem, eating small meals is crucial, the researchers say.
The new research confirms previous research, says John W. Baker, MD, president of the American Society for Metabolic and Bariatric Surgery and co-director of bariatric surgery, director of the medical weight loss program, and director of the general surgery residency program at Baptist Health in Little Rock, Ark.
"This is a randomized trial, that's an additional strength, banding kids did better," he tells WebMD. However, he says, the study "is not discounting the fact that medical treatment can help some."
In fact, the study ''has something for everybody," says Edward H. Livingston, MD, professor and chairman of gastrointestinal and endocrine surgery at the University of Texas Southwestern Medical Center in Dallas, who wrote an editorial to accompany the study.
''You can have an impact on kids no matter what you do," he tells WebMD. The teens in the lifestyle intervention group did not have nearly as much weight loss as the banding group, he says, but they did have improvements in medical conditions that can accompany excess weight, such as blood pressure reductions.
Another value of the research, he says, is to supply scientific evidence that the banding does work for teens, information that is crucial for insurance companies to have when considering whether to pay for the surgery.
The new study results are consistent with those by others that have looked at adults, says Paresh C. Shah, MD, chief of laparoscopic services at Lenox Hill Hospital in New York, who also reviewed the study for WebMD. But the Australian researchers, he says, "have added to the experience and understanding of the role for surgery in the most challenging and controversial of patients, the obese adolescent."
Even so, he says, no one, including the researchers, promotes the surgery as a cure. "It's the most effective long-term treatment modality," Shah says of bariatric surgery. The researchers, he says, "are careful to emphasize surgery is not a cure. There is still a lot of compliance necessary on the patient's and family's behalf."