Surgical Versus Medical Treatment of Type 2 Diabetes Mellitus in Nonseverely Obese Patients

In Brief Objective: To compare surgical versus medical treatment of type 2 diabetes mellitus (T2DM) remission and comorbidities in patients with a body mass index (BMI) less than 35 kg/m2. Background: Obesity surgery can achieve remission of T2DM and its comorbidities. Metabolic surgery has been proposed as a treatment option for diabetic patients with BMI less than 35 kg/m2 but the efficacy of metabolic surgery has not been conclusively determined. Methods: A systematic literature search identified randomized (RCT) and nonrandomized comparative observational clinical studies (OCS) evaluating surgical versus medical T2DM treatment in patients with BMI less than 35kg/m2. The primary outcome was T2DM remission. Additional analyses comprised glycemic control, BMI, HbA1c level, remission of comorbidities, and safety. Random effects meta-analyses were calculated and presented as weighted odds ratio (OR) or mean difference (MD) with 95% confidence intervals (95% CI). Results: Five RCTs and 6 OCSs (706 total T2DM patients) were included. Follow-up ranged from 12 to 36 months. Metabolic surgery was associated with a higher T2DM remission rate (OR: 14.1, 95% CI: 6.7–29.9, P < 0.001), higher rate of glycemic control (OR: 8.0, 95% CI: 4.2–15.2, P < 0.001) and lower HbA1c level (MD: −1.4%, 95% CI −1.9% to −0.9%, P < 0.001) than medical treatment. BMI (MD: −5.5 kg/m2, 95% CI: −6.7 to −4.3 kg/m2, P < 0.001), rate of arterial hypertension (OR: 0.25, 95% CI: 0.12–0.50, P < 0.001) and dyslipidemia (OR: 0.21, 95% CI: 0.10–0.44, P < 0.001) were lower after surgery. Conclusion: Metabolic surgery is superior to medical treatment for short-term remission of T2DM and comorbidities. Further RCTs should address the long-term effects on T2DM complications and mortality. This meta-analysis compares metabolic surgery with medical treatment for type 2 diabetes mellitus (T2DM) in nonseverely obese patients with body mass index (BMI) less than 35 kg/m2. Metabolic surgery is clearly superior to medical treatment alone with regard to T2DM remission (odds ratio: 14.1, 95% confidence interval: 6.7–29.9), glycemic control, and remission of other comorbidities. Because the majority of patients with diabetes have a BMI less than 35 kg/m2, this meta-analysis may trigger a fundamental change in the treatment of type 2 diabetes.