Metabolic surgery versus usual care effects on mortality among patients with obesity and type 2 diabetes: A systematic review and meta-analysis.

Although bariatric surgery is recommended for obesity treatment, there is an increasing trend toward comorbidity-related indications. The effects of bariatric surgery on mortality are inconsistent. This meta-analysis aimed to assess metabolic surgery versus usual care on mortality among patients with obesity and type 2 diabetes. we searched six databases for articles comparing bariatric surgery with usual care in terms of mortality. The terms used were bariatric surgery, metabolic surgery, lifestyles, usual care, gastric banding, bypass surgery, biliopancreatic diversion, gastric bypass, sleeve gastrectomy, and Roux-en-Y gastric bypass. The search engine was set for articles from inception up to June 2024. Out of the 1960 studies retrieved, 1810 were retained after the removal of duplication; from them, 75 full texts were eligible, and only 26 studies were included in the final meta-analysis. The study included 866,159 patients (167,152 patients who underwent bariatric surgery and 699,007 usual care patients) and 91,211 deaths. Mortality was lower among patients with bariatric surgery compared to usual care (3.1% vs. 12.6%), odds ratio = 0.43, 95% confidence interval (CI), 0.32-0.58, Chi-square = 1638.20, and P < 0.001, I ² for heterogeneity = 99%, and the standard difference = 24. Mortality was higher in bariatric surgery in subgroup meta-analysis on patients with type 2 diabetes (2.6% versus 2.0%), odds ratio, 0.63, 95% CI, 0.42-0.95, Chi-square = 101.04, and P = 0.03 I ² for heterogeneity = 95%, and the standard difference = 5. Bariatric surgery was associated with lower mortality in patients with obesity compared to usual care, but higher mortality in subgroup meta-analysis in type 2 diabetes. Larger, well-controlled trials are needed.