麻豆传媒

In the final, 5-year outcomes of the trial, named STAMPEDE (Surgical Treatment and Medications Potentially Eradicate Diabetes Efficiently), bariatric surgery prevailed as the more successful treatment for type 2 diabetes versus intensive medical therapy alone.

, of the Cleveland Clinic, and colleagues, reported bariatric surgery patients had a greater average percentage reduction in glycated hemoglobin levels (2.1% [surgery] versus 0.3% [medical therapy]; P=0.003). The results of the randomized, controlled trial were published in .

Previously, the 3-year follow-up results of STAMPEDE were presented as a late-breaking clinical trial at the American College of Cardiology's 2014 annual meeting.

The single-center trial randomized 150 obese individuals with type 2 diabetes, ages 20 to 60, into three equal groups: those having gastric bypass with intensive medical therapy, those having sleeve gastrectomy with intensive medical therapy, and those having medical therapy alone; 134 participants completed the 5-year follow-up period.

One late re-operation, converting sleeve gastrectomy to gastric bypass, was reported during the trial, as well as one patient death in the medical therapy group due to myocardial infarction.

The authors said that through assessing the 5-year follow-up data, they had hoped to address questions regarding the relative long-term efficacy and safety of bariatric surgery and its effects on diabetes-related end-organ disease.

Using a Pearson's chi-square test or Fisher's exact test, the authors reported that significantly more patients who underwent bariatric surgery reached their goal of a glycated hemoglobin (HbA1c) level of 6.0% or less with or without the use of diabetes medications, whereas only 5% of patients receiving medical therapy alone reached this goal (two of 38 patients).

In comparison, gastric bypass patients experienced greater success after 5 years, with 29% of patients reaching an HbA1c of 6.0% or less (14 of 49 patients; unadjusted P=0.01; adjusted P=0.03; intention-to-treat P=0.08). Sleeve gastrectomy patients also achieved substantial HbA1c success, with 23% of participants reaching their goal compared with the medical therapy group (11 of 47 patients; unadjusted P=0.03; adjusted P=0.07; intention-to-treat P=0.17).

An intention-to-treat analysis included an assessment of baseline through 5-year follow-up change among all participants.

The bariatric group also experienced more drastic improvements in many of the secondary outcomes, including several cardiometabolic factors and quality-of-life scores, assessed by a 36-item RAND Health Survey, when compared with the medical therapy group (P<0.05 for all):

• Body weight: -23%, -19%, -5% (gastric bypass, sleeve gastrectomy, and medical therapy, respectively)
• Triglyceride level: -40%, -29%, -8%
• High-density lipoprotein cholesterol: 32%, 30%, 7%
• Use of insulin: -35%, -34%, -13%
• Quality of life: 17, 16, 0.3

Although there were no significant differences reported for blood pressure and low-density lipoprotein cholesterol levels between the surgery and medical therapy groups, hyperlipidemia and hypertension medication usage decreased among the surgery group (P<0.05). Among the surgery group, no participants had excessive weight gain through the trial, compared with 19% of medical therapy patients (P<0.001).

The researchers said they were pleasantly surprised by the findings by the end of the trial period: "We expected bariatric surgery to work, but were surprised that at 5 years, 29% were able to have tight control of diabetes with little or no insulin," one of the co-investigators, , also of the Cleveland Clinic, told 麻豆传媒 via email.

Current recommending bariatric surgery as an option for treating type 2 diabetes state that metabolic surgery should be considered as a treatment among patients with a body mass index (BMI) of 35 or greater. If the patient has diabetes not well controlled with medication such as insulin, surgery should be considered for patients with a BMI of 30 or greater, according to the guidelines.

The researchers noted that despite the benefit to glycemic control for patients with type 2 diabetes with a BMI of 27 to 34, "nearly all financial-coverage policies for bariatric surgery worldwide (public and private) exclude patients with a BMI of less than 35."

Future research is suggested to assess potential differences between gastric bypass and sleeve gastrectomy for long-term weight loss and need for diabetes medications, the team continued. "While the current trial found that gastric bypass was associated with greater benefits for type 2 diabetes patients, the trial was not powered sufficiently to detect small but clinically significant differences between the two procedures."

The authors also recommend that "larger, multicenter trials" be conducted in the future to determine "the potential benefits of bariatric surgery on clinical endpoints, such as myocardial infarction, stroke, renal failure, blindness, and death."

Watch Philip R. Schauer, MD, discuss bariatric surgery as a treatment for patients with type 2 diabetes in 麻豆传媒's exclusive "Hot Topics" video. Click for the American Association of Clinical Endocrinologists/American College of Endocrinology's comprehensive type 2 diabetes management algorithm.

Comment