Meta-analysis of metabolic surgery versus medical treatment for macrovascular complications and mortality in patients with type 2 diabetes

Background: Although research has shown that metabolic surgery is superior to medical therapy in terms of glycemic control and other cardiovascular risk factors, it remains unclear whether these beneficial effects ultimately result in a reduced incidence of macrovascular complications or mortality in patients with type 2 diabetes. Objective: This meta-analysis assesses the impact of metabolic surgery versus medical therapy on mortality and macrovascular complications in patients with type 2 diabetes. Setting: Academic centers in the United States, Europe, and Asia. Methods: An unrestricted systematic literature search of MEDLINE, Web of Science, and Cochrane Central Register of Controlled Trials was performed. Randomized controlled trials (RCTs), case control trials, and cohort studies comparing the effect of metabolic surgery on mortality and the incidence of diabetes-associated macrovascular complications to a medically treated control group were identified. The last search was performed on June 15, 2018. Results: The literature search yielded 3721 potentially eligible articles. Nineteen studies (6 RCTs, 13 nonrandomized studies) were ultimately included. Metabolic surgery was found to be associated with reduced mortality (odds ratio .34, 95% confidence interval [.25.46], P < .00001) and macro vascular complication rates (odds ratio .38, 95% confidence interval [.22.671, P = .0008). Conclusions: Because metabolic surgery is associated with lower mortality and macrovascular complication rates than medical therapy, it seems to be the superior treatment choice for patients with type 2 diabetes. Additional, high-quality RCTs with adequate follow-up comparing state of the art surgical and medical therapies including glifozins and liraglutide are nevertheless needed to identify which patients would benefit most from metabolic surgery. (C) 2019 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.