The effects of metabolic surgery on microvascular complications in obese patients with type 2 diabetes: a meta-analysis

Background: Metabolic surgery is a standard treatment for obesity with type 2 diabetes (T2D), although the effects of metabolic surgery on the incidence rate of microvascular complications remain controversial. Objectives: We aimed to evaluate the effect of metabolic surgery versus nonsurgical treatments on the incidence rate of microvascular complications in obesity with T2D. Setting: A meta-analysis of published studies. Methods: We searched PubMed, Web of Science, and the Cochrane Library to identify clinical studies assessing the effect of metabolic surgery on the incidence rate of microvascular diabetic complications compared with that of nonsurgical treatments. We extracted the primary outcomes, including the incidence rate of microvascular complications after metabolic surgery. Results: A total of 32,756 participants from 12 studies were identified. Metabolic surgery reduced the incidence rate of microvascular complications (odds ratios [OR],.34; 95% confidence intervals [CI],.30-.39; P < .001) compared with that of nonsurgical treatments in obesity with T2D. Moreover, metabolic surgery also reduced the incidence of diabetic nephropathy (OR,.39; 95% CI,.30-.50; P < .001), diabetic retinopathy (OR,.52; 95% CI,.42-.65; P < .001) and diabetic neuropathy (OR,.27; 95% CI,.22-.34; P < .001) compared with nonsurgical treatments in obesity with T2D. Conclusion: Metabolic surgery was superior to nonsurgical treatments in reducing the incidence of microvascular complications in obesity with T2D. Prospective studies, preferably randomized controlled trials, with evaluations of different types of metabolic surgery arewarranted to provide guidelines for treatment preferences in obesity with T2D. (C) 2020 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.