Potential underutilisation of weight loss medications in obese patients with knee osteoarthritis.
TL;DR
Current pathways for managing obese patients with knee OA are inadequate and GLP-1 RAs may offer a promising solution to help reduce barriers to surgery, according to this study.
Abstract
INTRODUCTION Obesity is a major risk factor for knee osteoarthritis (OA), contributing to earlier symptomatic onset, increased pain severity and greater lifetime disability. Despite guidance that weight alone should not limit access to total knee arthroplasty (TKA), body mass index (BMI) thresholds are applied widely in clinical practice. This study investigated the glucagon-like peptide-1 (GLP-1) receptor agonist (RA) use among obese OA patients awaiting TKA and evaluated the influence of BMI on access to TKA.
Methods
A 30% random sample of a single-centre TKA waiting list (n = 300) in August 2025 was analysed. Data extracted included age, sex, BMI, time on waiting list, surgical listing status, comorbidities and use of weight loss interventions. Patients were stratified by BMI category (<35, 35-40, >40) and sex.
Results
Median BMI was 33.0 [27.9-38.0], with 120 patients (40%) classified as obese (BMI ≥35). Among obese patients, 45% were initially denied or conditionally listed for surgery, rising to 74.1% for BMI >40. Only 13 obese patients (10.8%) were taking GLP-1 RAs, despite extensive eligibility. Female patients had a higher average BMI (p = 0.049) and faced higher denial rates than male patients (52% vs 28%, p = 0.013). Most obese patients (n = 102) had ≥3 comorbidities, often including diabetes (n = 22) and obstructive sleep apnoea (n = 26).
Conclusion
Current pathways for managing obese patients with knee OA are inadequate. GLP-1 RAs may offer a promising solution to help reduce barriers to surgery. Further research is needed to determine whether GLP-1 RAs could help reduce the progression of OA and need for TKA.