One of the major reasons why we might suggest bariatric (obesity) surgery to our patients with obesity and type 2 diabetes, is that studies have shown bariatric surgery to be very effective in improving diabetes control, or even putting diabetes into remission. However, it has been slow to grow the body of research data in this area, as it is difficult to conduct high quality, long term studies in this field.
Now, just published, we have 5 year data showing that bariatric surgery (gastric bypass surgery and sleeve gastrectomy) are superior to medical therapy to treat type 2 diabetes in people with obesity.
I blogged on the 3 year data in this trial, called the STAMPEDE trial, when it came out in 2014 – where you can read about the structure, goals of the study and the results at that time.
Now, published in the New England Journal of Medicine, the extended results of the STAMPEDE study show that 5 years after bariatric surgery, 29% of patients who had gastric bypass surgery had tight control of their diabetes, vs 23% of those who had sleeve gastrectomy, vs only 5% of those who had intensive medical treatment alone. A duration of diabetes of less than 8 years before surgery was the main predictor of achieving tight control of diabetes, suggesting that earlier intervention with bariatric surgery may give the maximum benefit in glycemic control.
There were also greater improvements in body weight, several measures of cholesterol, need for insulin, and quality of life in the surgical groups. No late major surgical complications were reported except for one person in the sleeve gastrectomy group who underwent gastric bypass at year 4 to treat a gastric fistula. Follow up at the 5 year mark was 90%, which is excellent.
While I still take issue to the target for diabetes control being too tight in this study at an A1C of 6.0%, this study does now give us good 5 year data to support that bariatric surgery can be an effective tool to help treat type 2 diabetes in people with obesity.