Abstract
BACKGROUND: Obesity and metabolic disease are increasingly prevalent in patients with inflammatory bowel disease (IBD) and can influence disease activity and treatment outcomes. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are effective for weight loss and metabolic control, yet their safety and effects in IBD remain uncertain as patients with IBD have been excluded from pivotal trials. AIMS: To systematically evaluate the weight-related, metabolic, IBD-specific, and safety outcomes of GLP-1 receptor agonists in adults with IBD. METHODS: We conducted a systematic review according to PRISMA guidelines (PROSPERO CRD42025628850). We searched MEDLINE, Embase, Cochrane Library and ClinicalTrials.gov to 9 September 2025 for studies evaluating GLP-1 RAs in adults with IBD. Primary outcomes were weight-related measures. Secondary outcomes included metabolic parameters, IBD activity, and safety. Risk of bias was assessed using Joanna Briggs Institute (JBI) checklists. RESULTS: We included 14 studies of which 13 were retrospective cohort studies. Ten reported significant reductions in body weight, BMI, or percent weight loss. Four demonstrated improvements in metabolic markers, including decreased haemoglobin A1c and favourable lipid changes. Across multiple datasets, GLP-1 RA use was not associated with increased IBD exacerbations. Several large registries reported reduced risks of corticosteroid use, hospitalisation and surgery among GLP-1 RA users. Adverse events were primarily gastrointestinal, consistent with non-IBD populations. CONCLUSION: GLP-1 RAs appear to be well tolerated in patients with IBD, with observational evidence suggesting potential associations with improved weight, metabolic, and disease-related outcomes. Prospective, IBD-specific studies are required to confirm safety, clarify mechanisms, and define optimal patient selection.