Efficacy of GLP-1 receptor agonists on weight loss, body mass index and waist circumference for obese or overweight patients: A systematic review, meta-analysis and meta-regression of 47 randomized-controlled trials
Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have advanced rapidly in recent years.
Purpose
An updated synthesis on effects of GLP-1RAs on weight, BMI and waist circumference incorporating newer RCTs, particularly in overweight or obese patients, is timely.
Data Sources
We systematically searched PubMed, EMBASE and CENTRAL for RCTs published from inception to Oct 4, 2024.
Study Selection
The search was limited to RCTs evaluating the use of GLP1-RAs for mean differences from baseline in weight, BMI and waist circumference in obese or overweight adult patients with or without diabetes mellitus.
Data Extraction
Two independent reviewers performed the literature search and data extraction, resolving disagreements via consensus or third reviewer consultation.
Data Synthesis
47 RCTs were included with a combined cohort of 23,244 patients. GLP-1RAs demonstrated a mean weight reduction of -4.57 kg (95% CI -5.35 to -3.78), mean BMI reduction of -2.07 kg/m2 (95% CI -2.53 to -1.62), and mean waist circumference reduction of -4.55 cm (95% CI -5.72 to -3.38) compared to placebo. This effect was consistent across diabetic status, GLP-1RA used and route of administration. The greatest treatment benefit appeared to favour patients who were younger, female, non-diabetic, with higher baseline weight and BMI, but lower baseline HbA1c, and treated over a longer duration.
Limitations
Limitations include substantial statistical heterogeneity, in part due to broad inclusion criteria. However, this heterogeneity may improve generalizability by reflecting a wide range of study designs and patient populations.
Conclusions
GLP-1RAs demonstrated significant weight, BMI, and waist circumference reduction benefits in this meta-analysis.