Roux-en-Y Gastric Bypass vs Intensive Medical Management for the Control of Type 2 Diabetes, Hypertension, and Hyperlipidemia: The Diabetes Surgery Study Randomized Clinical Trial

Study Questions:

Does the Roux-en-Y gastric bypass improve the control of comorbid risk factors better than lifestyle and intensive medical management in obese diabetics?


A 12-month, two-group unblinded randomized trial was conducted at four teaching hospitals in the United States and Taiwan involving 120 participants who had a glycated hemoglobin (HbA1c) level of 8.0% or higher, body mass index (BMI) between 30.0 and 39.9 kg/m2, C peptide level of more than 1.0 ng/ml, and type 2 diabetes for at least 6 months. Interventions included lifestyle-intensive medical management intervention and Roux-en-Y gastric bypass surgery, and medications for hyperglycemia, hypertension, and dyslipidemia were prescribed according to protocol and surgical techniques that were standardized. Primary outcome was the composite goal of HbA1c <7.0%, low-density lipoprotein cholesterol <100 mg/dl, and systolic blood pressure <130 mm Hg.


Approximately 60% were women; mean age was 49 years, BMI was 34.5 kg/m2, blood pressure was 130/78 mm Hg, fasting blood sugar was 215 mg/dl, and HbA1c was 9.6%. All 120 patients received the intensive lifestyle-medical management protocol and 60 were randomly assigned to undergo Roux-en-Y gastric bypass. After 12 months, 28 participants (49%; 95% confidence interval [CI], 36%-63%) in the gastric bypass group and 11 (19%; 95% CI, 10%-32%) in the lifestyle-medical management group achieved the primary endpoints (odds ratio [OR], 4.8; 95% CI, 1.9-11.7). Participants in the gastric bypass group required 3.0 fewer medications (mean, 1.7 vs. 4.8; 95% CI for the difference, 2.3-3.6) and lost 26.1% versus 7.9% of their initial body weight compared with the lifestyle-medical management group (difference, 17.5%; 95% CI, 14.2%-20.7%). Regression analyses indicated that achieving the composite endpoint was primarily attributable to weight loss. There were 22 serious adverse events in the gastric bypass group, including one cardiovascular event, and 15 in the lifestyle-medical management group. There were four perioperative complications and six late postoperative complications. The gastric bypass group experienced more nutritional deficiency than the lifestyle-medical management group.


In mild to moderately obese patients with type 2 diabetes, adding gastric bypass surgery to lifestyle and medical management was associated with a greater likelihood of achieving the composite goal.


Intense lifestyle programs designed to reduce risk factors and improve control of diabetes have been successful, but recidivism is common. If bariatric surgical procedures with lower morbidities than the Roux-en-Y gastric bypass are effective and safe over the long-term, they may have a major complimentary role in diabetes and the metabolic syndrome. It is surprising that only 49% in the surgical and 19% of those in the nonsurgical group achieved the composite goal, which was likely related to poor baseline glycemic control.

Clinical Topics: Diabetes and Cardiometabolic Disease, Dyslipidemia, Prevention, Lipid Metabolism, Nonstatins, Hypertension

Keywords: Gastric Bypass, Hyperlipidemias, Diabetes Mellitus, Type 2, Comorbidity, C-Peptide, Risk Factors, Hemoglobin A, Glycosylated, Cholesterol, Dyslipidemias, Obesity, Morbid, Cardiovascular Diseases, Malnutrition, Confidence Intervals, Taiwan, Hypertension, United States, Odds Ratio, Postoperative Complications, Hyperglycemia, Bariatric Surgery, Weight Loss, Body Weight, Hospitals, Teaching, Metabolic Syndrome X, Body Mass Index, Blood Glucose, Regression Analysis, Diabetes Mellitus

< Back to Listings