BALTIMORE — A 2024 study by researchers at the University of Maryland School of Medicine found that GLP-1 receptor agonists such as semaglutide and tirzepatide were associated with a reduced long-term risk of knee replacement surgery in patients diagnosed with knee osteoarthritis. The study, published in Regional Anesthesia & Pain Medicine, analyzed data from 6.8 million adults diagnosed with the condition between 2010 and 2024.
Researchers identified a matched sample of 42,000 patients who had taken any type of GLP-1 medication for at least one year and compared them with an equal number of similar patients who had not. They also examined data for nearly 31,000 patients who had used GLP-1 medications for three years. All participants were tracked for eight years after diagnosis to assess whether they required knee replacement surgery.
Taking GLP-1 medications for one year was associated with a 1.4-percentage-point lower risk of knee replacement at the three-year follow-up and a 2.8-percentage-point reduced risk after eight years. Among those who used semaglutide or tirzepatide specifically for three years, the risk of needing surgery at the eight-year mark was nearly 5 percentage points lower. The authors estimated that if all eligible U.S. patients with knee arthritis and obesity or metabolic disease took these medications for three years, up to 14,400 fewer knee replacements could occur annually in the United States and more than 1,500 fewer in the United Kingdom.
"Our findings align with evidence that GLP-1 [receptor agonists] may influence knee [osteoarthritis] through complementary anti-inflammatory and analgesic mechanisms." The study authors added, "There may be some direct anti-inflammatory and possibly cartilage-protective effects of GLP-1 receptor agonists that operate through weight-independent mechanisms." However, Mark Bowditch, consultant knee surgeon and immediate past president of the British Orthopaedic Association, cautioned that "GLP-1 receptor agonists are not approved for the treatment of osteoarthritis, and we would strongly caution against their use for this purpose outside of clinical trials."
Lucy Donaldson, director of research at Arthritis UK, supported the study’s implications, stating, "The findings could help better understand the potential impact of weight-loss medications to help some patients avoid or delay the need for joint replacement surgery." She added, "Maintaining a healthy weight can play a vital role in managing osteoarthritis, particularly in weight-bearing joints such as the knees and hips."