Glucagon-like peptide 1 analog treatment reduces total adipose tissue, primarily affecting the visceral, epicardial, and liver adipose tissues, according to research published in Obesity Reviews.
Researchers performed a systematic review and meta-analysis to determine associations between glucagon-like peptide 1 analogs and adipose tissue distribution. The team searched PubMed, Cochrane, and Scopus databases and included 35 studies in the meta-analysis. Primary endpoints included changes in epicardial, visceral, subcutaneous, liver, and total adipose tissue and waist-to-hip ratio (W:H).
The investigators quantified glucagon-like peptide 1 analog treatment effects using standardized mean difference (SMD), with negative SMDs indicating reduced adiposity. A SMD less than 0.4 indicated a small effect size, SMD between 0.4 and 0.7 showed a moderate effect size, and SMD greater than 0.7 indicated a large effect size. The team used individual random effect models to estimate effect size for each endpoint and meta-regression models to account for heterogeneity.
Overall, glucagon-like peptide 1 analog treatment was associated with significant decreases in total adiposity tissue (SMD, -0.77; 95% CI, 1.22 to -0.32; P <.001) in 12 datasets, subcutaneous adipose tissue (SMD, -0.64; 95% CI, -1.35-0.07; P =.008) in 9 datasets, visceral adipose tissue (SMD, -0.64; 95% CI, -1.10 to -0.17; P =.007) in 13 datasets, epicardial adipose tissue (SMD, -1.56; 95% CI, -2.86 to -0.26; P =.02) in 4 datasets, and liver adipose tissue (SMD -0.94; 95% CI, -1.70 to -0.18; P =.02) in 12 datasets. The treatment did not significantly reduce W:H (SMD, -0.28; 95% CI, -0.60-0.04; P =.08) in 10 datasets.
The team achieved similar results after excluding the highest effect study for each outcome and after applying a correlation coefficient of 0.8 in a repeat analysis, according to the report.
Study limitations include potential confounding due to differences in patient population baseline characteristics and comorbidities between studies, which may have led to significant heterogeneity.
“These findings corroborate the previously established attenuating effect of [glucagon-like peptide 1] analog treatment on body weight, mainly indicated by BMI, and suggest a generalized effect of [glucagon-like peptide 1] on body adiposity, spanning most studied [adipose tissue] depots,” according to the study authors. “Importantly, this effect includes [visceral adipose tissue] and [liver adipose tissue], two depots strongly associated with obesity-related metabolic derangements including the metabolic syndrome.”
Akoumianakis I, Zagaliotis A, Konstantaraki M, Filippatos TD. GLP-1 analogs and regional adiposity: a systematic review and meta-analysis. Obes Rev. Published online May 16, 2023. doi:10.1111/obr.13574