Comparative effectiveness of metabolic and bariatric surgeries: a network meta-analysis

Bariatric surgery is recommended for patients with unhealthy weight. Our study aim to compare and rank different bariatric surgical approaches in reducing weight parameters. We searched MEDLINE, Cochrane CENTRAL, Scopus, and Web of Science databases from inception to September 2023. We extracted all outcomes as mean change from the baseline. The mean difference and 95% confidence interval were used as a summary measure. All analysis was conducted with R version 4.2.2 (2022-10-31) and R Studio version 2022.07.2 (2009-2022) (RStudio, Inc.). Included surgeries were: Biliopancreatic diversion (BPD-RYGB), Roux-en-Y Gastric Bypass (RYGB), Laparoscopic Gastric Plication (LGP), Duodenal-Jejunal Bypass Sleeve (DJBS), Single-anastomosis gastric bypass (SAGB), Laparoscopic vertical banded gastroplasty (LVBG), Sleeve Gastrectomy (SG), Laparoscopic adjustable gastric banding (LAGB), Gastric plication, Biliopancreatic diversion (BPD), and Intra-gastric balloon (IGB). Only clinical trials were included, with outcomes focused on weight parameters such as reductions in BMI (kg/m²), weight (kg), waist circumference (cm), fat mass (kg), and excess weight loss (EWL) (%). Our analysis of 67 studies showed that SADI-S was the best surgical technique in decreasing BMI (kg/m2) (MD = -18.06; 95% CI [-25.31; -10.81]) and DS follows in efficacy with a P-score (MD = -18.88; 95% CI [-31.15; -6.62]) however the pooled analysis was heterogeneous (I² = 98.5%). For weight (kg), waist circumference (cm), and fat mass (kg), BPD-RYGB was the best surgical technique to reduce these parameters (MD = -41.48; 95% CI [-47.80, -35.51], MD = -29.08; 95% CI [-37.16, -21.00], and MD = -31.11; 95% CI [-38.77, -23.46]; respectively). The pooled analysis was heterogeneous except in fat mass (I² = 0%, p-value = 0.8). Our network meta-analysis showed that the best surgical technique in increasing EWL (%) was RY-DS (MD = -61.27; % CI [-91.72; -30.82]) the next one in efficacy according to P-score was LVBG (MD = -59.03; % CI [-84.47; -33.59]). SADI-S is most effective in reducing BMI followed by RYGB. DS was associated with most estimated weight loss %.