Characterizing body composition modifying effects of a glucagon-like peptide 1 receptor-based agonist: A meta-analysis

Aim: Diabetes is an independent risk factor for muscle mass loss, with possible mechanisms including impaired insulin signalling and chronic inflammation. The use of a glucagon-like peptide 1 (GLP-1) receptor-based agonist could lead to weight reduction, which might result from the loss of both fat and skeletal muscle. However, the body composition-modifying effects of GLP-1 receptor-based agonists have not been systematically characterized. Methods: PubMed, EMBASE, the Cochrane Center Register of Controlled Trials for Studies and Clinicaltrial.gov were searched from inception to October 2023. Randomized controlled trials of GLP-1 receptor agonist or glucose-dependent insulinotropic polypeptide/GLP-1 receptor dual agonist, which reported the changes of body composition, were included. The results were computed as weighted mean differences (WMDs) and 95% confidence intervals (CIs) in a random-effects model. Results: In all, 19 randomized controlled trials were included. When compared with controls, substantial reductions in fat body mass were observed in patients using GLP-1 receptor-based agonist treatment (WMD = −2.25 kg, 95% CI −3.40 to −1.10 kg), with decrease in areas of both subcutaneous fat (WMD = −38.35 cm², 95% CI, −54.75 to −21.95 cm²) and visceral fat (WMD = −14.61 cm², 95% CI, −23.77 to −5.44 cm²). Moreover, greater reductions in lean body mass were also observed in GLP-1 receptor-based agonist users compared with non-users (WMD = −1.02 kg, 95% CI, −1.46 to −0.57 kg), while the changes in lean mass percentage were comparable between GLP-1 receptor-based agonist users and non-users. Conclusion: Compared with the controls, GLP-1 receptor-based agonist users experienced greater reductions in fat body mass, with body shaping effects in terms of both subcutaneous fat mass and visceral fat mass. Although greater reductions in lean body mass were also observed in GLP-1 receptor-based agonist users, the changes in lean mass percentage were comparable between the users and non-users.