Five-Year Results of STAMPEDE Trial Show Bariatric Surgery’s Efficacy on Treating T2D

Researchers at Cleveland Clinic last month published the five-year results of STAMPEDE, a groundbreaking trial that compared intensive medical treatment and surgical treatment of uncontrolled type 2 diabetes (T2D). The results, published in the New England Journal of Medicine, showed that bariatric surgery plus intensive medical intervention was more effective in treating T2D than intensive medical intervention alone.

The researchers, led by Sangeeta R. Kashyap, MD, professor of medicine, and Philip R. Schauer, MD, professor of surgery, point out that observational studies and randomized, controlled trials have shown that bariatric surgery used specifically to treat diabetes significantly improves glycemic control and reduces cardiovascular risk factors, but these have mostly been short-term studies. As part of their ongoing Surgical Treatment and Medications Potentially Eradicate Diabetes Efficiently (STAMPEDE) Trial, the team has shown that patients experienced positive outcomes at one and three-year randomization, especially after gastric bypass and sleeve gastrectomy procedures, which they found to be superior to medical therapy alone. Now, they have results on this final, five-year follow-up. They write that this study “attempts to address questions regarding the relative long-term efficacy and safety of bariatric surgery and its effects on diabetes-related end-organ disease.”

The researchers assessed outcomes five years after 150 patients with type 2 diabetes and a BMI of 27 to 43 randomly received intensive medical therapy alone or intensive medical therapy plus Roux-en-Y gastric bypass or sleeve gastrectomy. Of these patients, 134 complete the five-year follow-up. The primary goal the team wanted to see patients meet was a glycated hemoglobin level of 6.0% or less with or without the use of diabetes medications. “At 5 years,” the authors write, “the criterion for the primary end point was met by 2 of 38 patients (5%) who received medical therapy alone, as compared with 14 of 49 patients (29%) who underwent gastric bypass (unadjusted P = 0.01, adjusted P = 0.03, P = 0.08 in the intention-to–treat analysis) and 11 of 47 patients (23%) who underwent sleeve gastrectomy (unadjusted P = 0.03, adjusted P = 0.07, P = 0.17 in the intention-to-treat analysis).” The continue that the patients who had surgical procedures saw greater reduction in glycated hemoglobin levels than patients who received medical therapy alone, the surgical group lost more weight than the medical-therapy group, used less insulin, and reported an improved quality of life.

Based on these findings, the authors conclude: “Five-year outcome data showed that, among patients with type 2 diabetes and a BMI of 27 to 43, bariatric surgery plus intensive medical therapy was more effective than intensive medical therapy alone in decreasing, or in some cases resolving, hyperglycemia.” They go on to write that these beneficial effects are durable, even in patients with mild obesity and that the effects of bariatric surgery on clinical endpoints like myocardial infarction, renal failure, blindness, and death should be examined further.