Aims: Clinical obesity is a major contributor to adverse health outcomes and treatment remains a significant challenge. Glucagon-like peptide-1 receptor agonists (GLP-1RA) are an effective tool for weight loss, however there is limited evidence for individuals with higher body mass index (BMI) ≥50kg/m2 and costs can be prohibitive. Our aim was to evaluate weight loss outcomes and tolerability of cost-subsidised GLP-1RA in people with extreme obesity (BMI ≥50kg/m2).
Methods: A retrospective audit was performed on individuals treated with cost-subsidised GLP-1RA (semaglutide and/or liraglutide) at a tertiary Complex Obesity Service between March 2021 and June 2025. Eligibility criteria were BMI ≥60kg/m2 or weight ≥180 kg, or BMI ≥50kg/m2 or weight ≥160 kg with ≥1 significant obesity-related comorbidity. The main outcomes were change in weight and BMI at both nadir and last follow-up, treatment duration, and adverse effects.
Results: Thirty-seven individuals were approved for cost-subsidised GLP-1RA therapy, of whom thirty-one had adequate data for analysis. At baseline, the mean (SD) age was 47.3 (13.6) years, median (IQR) weight was 182.4kg (152-246), and BMI was 65.5 kg/m2 (54-75). Median semaglutide dose was 1mg weekly (n=30) and liraglutide dose was 3mg daily (n=10). Median maximal weight loss was 15.5kg (9-26), or 9.3% (5-15), over a median of 10 months (5-15). At last follow-up (median 13 months [8-22]), median weight loss was 14.9kg (7-23), or 7.2% (4-13). Nineteen (61%) individuals achieved ≥5% and 13 (42%) achieved ≥10% weight loss at last follow-up. Twelve (39%) people experienced gastrointestinal adverse effects and six (19%) discontinued due to adverse effects.
Conclusion: Cost-subsidised GLP-1RA enabled clinically significant weight loss in a cohort of people with BMI ≥50kg/m2, and although well-tolerated by most, gastrointestinal adverse effects were common. These results demonstrate a promising role for GLP-1RA in the management of those with extreme obesity.