Benefits of bariatric surgery on microvascular outcomes in adult patients with type 2 diabetes: a systematic review and meta-analysis

BackgroundMicrovascular diabetes complications impair patients’ health-related quality of life. Bariatric surgery (BS) emerged as a compelling treatment that demonstrated to have beneficial effects on patients with diabetes and obesity.ObjectiveWe aimed to synthesize the benefit of bariatric surgery on microvascular outcomes in adult patients with type 2 diabetes.Setting2011-2021.MethodsWe included both cohort studies and randomized trials that evaluated bariatric surgery added to medical therapy compared with medical therapy alone in the treatment of adult patients with type 2 diabetes. Studies must have evaluated the incidence of any microvascular complication of the disease for a period of at least 6 months. We performed our search using PubMed, Scopus, EMBASE, Web of Science, and COCHRANE Central database which was performed from inception date until March 2021. PROSPERO (CRD42021243739).ResultsA total of 25 studies (160,072 participants) were included. Pooled analysis revealed bariatric surgery to reduce the incidence of any stage of retinopathy by 71% (odds ratio [OR] .29; 95% confidence interval [CI] .10–.91), nephropathy incidence by 59% (OR .41; 95% CI 17–96), and hemodialysis/end-stage renal disease by 69% (OR .31 95% CI .20–.48). Neuropathy incidence revealed no difference between groups (OR .11; 95% CI .01–1.37). Bariatric surgery increased the odds of albuminuria regression by 15.15 (95% CI 5.96–38.52); higher odds of retinopathy regression were not observed (OR 3.73; 95% CI .29–47.71). There were no statistically significant differences between groups regarding the change in surrogate outcomes.ConclusionsBariatric surgery in adult patients with diabetes reduced the odds of any stage of retinopathy, hemodialysis/end-stage renal disease, and nephropathy composite outcome. However, its effect on many individual outcomes, both surrogates, and clinically significant, remains uncertain.