Adjunctive use of glucagon-like peptide-1 receptor agonists after bariatric surgery: updated systematic review and meta-analysis of randomized controlled trials

AIMS: We meta-analyzed randomized trials to assess efficacy and safety of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) after bariatric surgery. METHODS: We searched PubMed, Embase, and Cochrane Central for randomized trials comparing GLP-1 RAs with placebo after bariatric surgery. Primary outcomes were change in body weight (kg) and HbA1c (%) at 6 and 12 months. We also assessed percent total body weight loss (%TBWL), quality of life, and adverse events. We pooled mean differences (MDs) with 95% confidence intervals (CIs) using random effects and assessed heterogeneity with I² statistic. We also performed an exploratory subgroup analysis that compared very early (≤ 2 months) versus late (≥ 18 months) initiation after surgery. RESULTS: Seven RCTs (n = 460) met inclusion criteria; all evaluated liraglutide. GLP-1 RAs increased weight loss at 6 months (MD - 5.33 kg; 95% CI - 9.42 to - 1.23; p = 0.02) but not at 12 months (MD - 5.05 kg; 95% CI - 22.14 to 12.05; p = 0.33). GLP-1 RAs increased %TBWL at 6 months (MD 5.13%; 95% CI 2.14 to 8.11; p = 0.007) but not at 12 months (MD 3.96%; 95% CI - 3.33 to 11.26; p = 0.18). HbA1c did not differ at 6 or 12 months. Quality of life improved at 6 months in the trials reporting this outcome. Gastrointestinal adverse events were similar between groups. Subgroup analyses suggested differences by initiation timing. CONCLUSION: GLP-1 RA therapy improved short-term weight outcomes after bariatric surgery, with no statistically significant between-group differences at 12 months. Timing of initiation may influence response and should be explored in trials with longer follow up. TRIAL REGISTRY: PROSPERO ID CRD420251251321.