written by Michael O’Leary
In a study that could lead to changes in doctors’ recommendations about weight-loss surgery for people at risk for type 2 diabetes, researchers have shown that the procedure may be twice as effective in preventing the disease as lifestyle changes.
The Swedish study in this week’s New England Journal of Medicine compared 1,658 obese patients who underwent weight-loss (bariatric) surgery with 1,771 obese people who underwent usual treatment including diet and exercise. None of the patients in either group had been diagnosed with type 2 diabetes at the start of the study.
All of the men in the two groups had a body-mass index (BMI) of 34 or more and the women had BMI of 38 or more. A normal BMI ranges from 19-25, and obesity is defined as a BMI of 30 or higher.
Bariatric surgery includes several different types of surgery, but all of them essentially reduce the volume of the stomach, which restricts the amount of food that can be consumed. In this study, among patients who underwent the bariatric surgery, 19 percent had the banding surgery, 69 percent had the vertical-banded gastroplasty and 12 percent had gastric bypass surgery.
The researchers then followed these patients for 15 years, and over that time 392 participants in the usual care group developed type 2 diabetes compared to 110 in the bariatric surgery group.
As reported by ABC News, lead author of the study Dr. Lena Carlsson of the University of Gothenburg, Sweden, wrote that the results show that surgery may be more effective for some people in preventing type 2 diabetes.
“Bariatric surgery appears to be markedly more efficient than usual care in the prevention of type 2 diabetes in obese persons,” Carlsson wrote in the study.
While a single study is never enough to change clinical practice, this study offers enough compelling evidence to generate larger studies to see if these results hold up among bigger groups of people who are obese, but without type 2 diabetes. If it does it is possible that surgery might be recommended for more people to prevent them from developing the disease.
Some of the limitations of this study, are that 36.2 percent of the original participants dropped out of the study, and at the time of this analysis, nearly 31 percent had not been followed for the full 15 years.
It should also be noted that surgery does have risks, and in this study, the risk of death in the surgery group was two in 1,000 (0.2 percent) and 2.8 percent of the surgery group needed a second operation due to complications.