GLP-1 drugs may offer cost-effective treatment for people with knee osteoarthritis and obesity

A new study led by investigators at Mass General Brigham finds that adding novel weight loss GLP-1 drugs semaglutide and tirzepatide to usual care represents a cost-effective treatment strategy for people with knee osteoarthritis and obesity, with tirzepatide providing greater health benefits at lower cost compared to semaglutide. The research comes as patients and providers seek to balance the benefits of weight loss and pain relief against the expense of these novel agents. Results are published in Annals of Internal Medicine. 

Weight loss can relieve joint pain, but semaglutide and tirzepatide are expensive and most insurance plans don't cover weight loss medications. This means that many patients can't afford these medications. This is why a formal economic analysis is valuable. It gives payers and policymakers the data they need to make informed coverage decisions and improve access to these weight loss treatments. Our goal is to ensure that payers and policymakers have the evidence they need to make informed decisions about coverage."

Elena Losina, PhD, senior author, Department of Orthopaedic Surgery, Brigham and Women's Hospital

The study was funded by Arthritis Foundation and National Institute of Arthritis, Musculoskeletal and Skin Diseases. The investigators used OApol, a validated and widely published computer simulation model, to conduct a cost-effectiveness analysis comparing the two GLP-1 drugs as well as two other common weight loss interventions: bariatric surgery and lifestyle modifications. They found that tirzepatide offered somewhat better value than semaglutide and would be the preferred option between the two drugs for most patients. For eligible and willing patients, bariatric surgery, which provides sustained benefits, may be the best option from a clinical and economic perspective.

Limitations of this analysis include its reliance on data integrated from multiple sources. In addition, conducting this study required researchers to make assumptions about the duration of time patients would remain on these medications, which may affect the findings.

"Osteoarthritis substantially reduces quality of life due to debilitating pain and limited mobility. Obesity has been shown to shorten life expectancy," said Losina. "Offering these drugs to patients with knee osteoarthritis and obesity improves both measures."