Comparative Efficacy of Metabolic/Bariatric Surgery Versus GLP-1 Receptor Agonists: A Network Meta-Analysis of Randomized Controlled Trials

Abstract

Objective: This study compared the efficacy of metabolic/bariatric surgery (MBS) and GLP-1 receptor agonists (GLP-1 RAs), including dual GLP-1/GIP analogues, for weight and metabolic outcomes in adults with obesity. Methods: A network meta-analysis of randomized controlled trials compared MBS or GLP-1 RAs versus lifestyle intervention in adults with overweight or obesity. Primary outcomes were percent total weight loss (TWL) and BMI; secondary outcomes included body weight, waist circumference, HbA1c, and systolic blood pressure. Random-effects models used lifestyle intervention as the common comparator; all MBS versus GLP-1 RA comparisons were indirect. Results: Thirty randomized controlled trials (n = 20,015) were included. At < 104 weeks, MBS achieved greater reductions than GLP-1 RAs in %TWL (ETD –10.3%; p = 0.001), BMI (−4.5 kg/m2; p < 0.001), body weight (−11.7 kg; p < 0.001), waist circumference (−12.6 cm; p < 0.001), and HbA1c (−0.5%; p = 0.033). At ≥ 104 weeks, differences remained for %TWL (−9.1%; p = 0.022) and body weight (−14.6 kg; p = 0.049). In tirzepatide-only analyses, differences versus MBS were not significant. Among participants with type 2 diabetes, MBS produced greater reductions in BMI, weight, waist, and %TWL, with similar HbA1c improvement. Conclusions: Both MBS and GLP-1 RAs provide substantial metabolic benefits. MBS remains superior, but tirzepatide is a promising nonsurgical option supporting personalized obesity care.