Bariatric surgery beats medical therapy alone for managing diabetes

Gastric bypass and sleeve gastrectomy - two of the most commonly used bariatric surgeries - are more effective than intensive medical therapy alone when it comes to managing uncontrolled type 2 diabetes in overweight or obese patients after three years, according to research presented at the American College of Cardiology's 63rd Annual Scientific Session.

STAMPEDE is the largest randomized controlled trial with one of the longest follow-ups to compare the effect of these two procedures to intensive medical therapy in helping patients achieve glycemic control, defined in this study as a three-month average blood glucose level of 6 percent or lower - a more aggressive target than the American Diabetes Association recommendation of 7 percent. At the three-year follow up, only 5 percent of patients in the medical therapy group met this primary endpoint compared with 37.5 percent of gastric bypass and 24.5 percent of sleeve gastrectomy patients. Surgical patients also had a significant improvement in key cardiovascular risk factors including body mass index, weight control, triglycerides and high-density lipoprotein cholesterol compared to those receiving medical therapy alone.

"Both surgical options maintain their supremacy over standard intensive medical therapy at the three-year mark," said Philip Schauer, M.D., professor of surgery, director of the Bariatric and Metabolic Institute, Cleveland Clinic, and lead investigator of the study. "There is this notion that if we keep adding medications and pushing patients to lose weight on their own, they will eventually achieve the same type of results as those undergoing surgery, but that wasn't the case here."

While the medical group showed an initial improvement in glycemic control within the first year, they were almost back to baseline by year three.

"Their [blood glucose level] went from 9.5 at the start of the study and dropped as low as 7.5 and then back up to 8.4 percent," he said. In contrast, the surgical groups were able to maintain a lower glucose level with an average 2.5 percent reduction (9.3 at baseline and 6.7 and 7.0 for gastric bypass and sleeve gastrectomy at year three).

A total of 150 patients, age 41 to 57, were randomly assigned to one of three treatment groups: intensive medical therapy only, which includes a combination of counseling, lifestyle changes and medications, medical therapy plus Roux-en-Y gastric bypass, or medical therapy plus sleeve gastrectomy. Nearly all patients, 91.3 percent, completed 36 months of follow up. At the start of the trial, the average patient had an average blood glucose level of 9.2 percent, was living with uncontrolled diabetes for eight or more years and was taking three or more anti-diabetic medications and three or more cardiovascular medications. All patients had some degree of obesity. The sample was 66 percent female.

After three years, weight loss was five to six times greater for patients who underwent gastric bypass or sleeve gastrectomy on average compared with those in the intensive medical therapy group. On average the gastric bypass group lost 24 percent of their body weight, sleeve gastrectomy patients lost 21percent of their weight, and those on medical therapy alone lost 4 percent.