CHICAGO – The superiority of metabolic surgery over intensive medical therapy for achieving glycemic control in patients with type 2 diabetes was largely maintained at the final 5-year follow-up evaluation in the randomized, controlled STAMPEDE trial.
The 150 subjects, who had “fairly severe diabetes” with an average disease duration of 8 years, were randomized to receive intensive medical therapy alone, or intensive medical therapy with Roux-en-Y gastric bypass surgery or sleeve gastrectomy surgery. The primary endpoint of hemoglobin A1c less than 6% was achieved in 5%, 29%, and 23% of patients in the groups, respectively. The difference was statistically significant in favor of both types of surgery, Dr. Philip Raymond Schauer reported at the annual meeting of the American College of Cardiology.
Furthermore, patients in the surgery groups fared better than those in the intensive medical therapy group on several other measures, including disease remission (defied as HbA1c less than 6% without diabetes medication), HbA1c less than 7% (the American Diabetes Association target for therapy), change in fasting plasma glucose from baseline, and changes in high- and low-density lipoprotein cholesterol levels, said Dr. Schauer, director of the Cleveland Clinic Bariatric and Metabolic Institute.
Patients in the surgery groups also experienced a significantly greater reduction in the use of antihypertensive medications and lipid-lowering agents, he added.
The “very dramatic drop” in HbA1c seen early on in the surgical patients was, for the most part, sustained out to 5 years, he said.
The results for both surgeries were significantly better than those for intensive medical therapy, but the results with gastric bypass were more effective at 5 years than were those for sleeve gastrectomy, he added, noting that the surgery patients had better quality of life, compared with the intensive medical therapy patients.
As for adverse events in the surgery groups, no perioperative deaths occurred, and while there were some surgical complications, none resulted in long-term disability, Dr. Schauer said.
Anemia was more common in the surgery patients, but was fairly mild. The most common complication was weight gain in 20% of patients, and the overall reoperation rate was 7%.
Of note, patients in the study had body mass index ranging from 27 to 43 kg/m2, and those with BMI less than 35 had similar benefits as those with more severe obesity. This is important, as many insurance companies won’t cover metabolic surgery for patients with BMI less than 35, he explained.
These findings represent the longest follow-up to date comparing the efficacy of the two most common metabolic surgery procedures with medical treatment of type 2 diabetes for maintaining glycemic control or reducing end-organ complications. Three-year outcomes of STAMPEDE (Surgical Treatment and Medications Potentially Eradicate Diabetes Efficiently) were reported in 2014 (N Engl J Med. 2014;370:2002-13).
The participants ranged in age from 20 to 60 years. The average HbA1c was about 9%, the average BMI was 36, and most were on at least three antidiabetic medications at baseline. Half were on insulin.
The findings are important, because of the roughly 25 million Americans with type 2 diabetes, only about half have good glycemic control on their current medical treatment strategies, Dr. Schauer said.
Though limited by the single-center study design, the STAMPEDE findings show that metabolic surgery is more effective long term than intensive medical therapy in patients with uncontrolled type 2 diabetes and should be considered a treatment option in this population, he concluded, adding that multicenter studies would be helpful for determining the generalizability of the findings.
Dr. Schauer reported receiving consulting fees/honoraria from Ethicon Endosurgery and The Medicines Company, and having ownership interest in Surgical Excellence.