Bariatric surgery is a highly effective long-term treatment for type 2 diabetes in obese patients, according to study findings presented at the annual meeting of the American College of Cardiology in Washington, D.C. and published online in The New England Journal of Medicine (NEJM).
The study, led by Philip R. Schauer, MD, director of the Cleveland Clinic’s Bariatric and Metabolic Institute, included 150 obese patients with uncontrolled type 2 diabetes. Subjects were participants in the STAMPEDE (Surgical Treatment and Medications Potentially Eradicate Diabetes Efficiently) trial. Patients underwent either intensive medical therapy alone or intensive medical therapy with surgery (gastric bypass or sleeve gastrectomy). The primary endpoint was a glycated hemoglobin level of 6.0% or less.
At 3 years, a significantly higher proportion of patients in the gastric bypass group (38%) met the primary endpoint compared with the sleeve-gastrectomy group (24%) or medical therapy group (5%).
In addition, use of insulin and other glucose-lowering medications was lower in both surgical groups than in the medical therapy group. Weight reduction compared with baseline was greater in the surgical groups compared to medical therapy, and quality-of-life was reportedly improved as well.
More than 90% of the patients who underwent bariatric surgery lost 25% of their body weight and controlled their diabetes without the use of insulin and multiple diabetes drugs, the study found.
“The three-year data confirm that bariatric surgery maintains its superiority over medical therapy for the treatment of type 2 diabetes in severely obese patients,” Dr. Schauer said in a press release issued by Cleveland Clinic. “Moreover, data show that bariatric surgery is as effective in treating type 2 diabetes in patients with mild obesity.”
The researchers observed no significant changes in patients at 3 years in blood pressure and LDL cholesterol levels among the three groups, although they did note a reduction in the number of required medications to treat hyperlipidemia and hypertension in both surgery groups.
Among patients with kidney disease, the researchers observed an improvement in albuminuria in the surgery groups despite a reduction in the use of renin-angiotensin system blockers, with a significant reduction in the albumin-to-creatinine ratio from baseline in both surgery groups compared with the therapy alone group.
“Cumulatively, our data should be considered to be hypothesis-generating and suggest the need for further long-term studies examining the effects of bariatric surgery on renal function in diabetes,” the authors wrote in their NEJM report.
The researchers acknowledged some important study limitations, including an inadequate sample size and duration to detect differences in the incidence of diabetes complications.
“Despite these limitations,” they observed, “we concluded that bariatric surgery represents a potentially useful strategy for the management of type 2 diabetes, allowing many patients to reach and maintain therapeutic targets of glycemic control that otherwise could not be achievable with intensive medical therapy alone.”