Disease-specific mortality and major adverse cardiovascular events after bariatric surgery: a meta-analysis of age, sex, and BMI-matched cohort studies

Obesity is associated with a significant predisposition towards cardiovascular events and acts as an important risk factor for mortality. Herein, we conducted a comprehensive meta-analysis to estimate the protective effect of bariatric surgery on disease-specific mortality and major adverse cardiovascular events (MACEs) in patients with severe obesity. METHODS: PubMed and Embase were searched from inception to 4 June 2022. Eligible studies were age, sex, and BMI-matched cohort studies. The protocol for this meta-analysis was registered on PROSPERO (ID: CRD42022337319). RESULTS: Forty matched cohort studies were identified. Bariatric surgery was associated with a lower risk of disease-specific mortality including cancer mortality [hazard ratio with 95% confidence interval: 0.46 (0.37–0.58)], cardiovascular mortality [0.38 (0.29–0.50)], and diabetes mortality [0.25 (0.11–0.57)]. Bariatric surgery was associated with a lower incidence of MACEs [0.58 (0.51–0.66)] and its components including all-cause mortality [0.52 (0.47–0.58)], atrial fibrillation [0.79 (0.68–0.92)], heart failure [0.52 (0.42–0.65)], myocardial infarction [0.55 (0.41–0.74)], and stroke [0.75 (0.63–0.89)]. According to subgroup analysis on all-cause mortality, patients with severe obesity and type 2 diabetes benefited more from bariatric surgery than those with severe obesity only (heterogeneity between groups: P=0.001), while different surgical approaches brought similar benefits (heterogeneity between groups: P=0.87). CONCLUSIONS: This meta-analysis of 40 matched cohort studies supports that bariatric surgery reduces disease-specific mortality and incidence of both MACEs and its components in patients with severe obesity compared with nonsurgical subjects. Bariatric surgery deserves a more aggressive consideration in the management of severe obesity.