Administering weight loss medications for a period of at least three years could prevent thousands of knee replacement surgeries (arthroplasty). This is a surgical procedure in which the worn-out joint is replaced with an artificial implant.
Globally, over 500 million people suffer from osteoarthritis. Knee arthritis is the most common form, affecting approximately 14 million people in the United States and over 5 million in the United Kingdom, writes The Guardian.
Many of these individuals will eventually require knee surgeries. In the United Kingdom, over 120,000 knee replacement surgeries are performed annually.
Excess weight significantly increases the risk of knee arthritis as it exerts greater pressure on the joints.
Previous studies have shown that weight loss medications can help reduce knee osteoarthritis pain.
Now, researchers have found that administering certain medications such as Mounjaro and Wegovy, or type 2 diabetes treatments like Ozempic, could also contribute to preventing the need for a knee replacement surgery.
Experts from the University of Maryland School of Medicine analyzed data from 6.8 million adults diagnosed with osteoarthritis between 2010 and 2024.
They then identified a sample of 42,000 individuals who had taken any type of GLP-1 class medication (for type 2 diabetes) for at least a year and compared it to an equal number of patients who had not undergone this treatment.
The researchers also analyzed data from nearly 31,000 patients who had taken these medications for three years.
The patients were periodically monitored for eight years after diagnosis to assess the need for a knee replacement surgery.
The study, published in Regional Anesthesia & Pain Medicine, found that taking GLP-1 medications for a year was associated with a 1.4 percentage point reduction in the risk of knee replacement surgery at the three-year assessment and a 2.8 percentage point reduction after eight years.
However, the greatest risk reduction was observed with newer weight loss medications and long-term treatment. Taking semaglutide or tirzepatide for three years was associated with a nearly 5 percentage point decrease in the likelihood of needing a knee prosthesis at the eight-year evaluation.
The authors estimated that if all eligible patients with knee arthritis and obesity or metabolic disease were to undergo treatment with semaglutide or tirzepatide for three years, up to 14,400 knee replacement surgeries could be avoided annually in the United States and over 1,500 annually in the United Kingdom.
Commenting on the results, Mark Bowditch, a knee specialist orthopedic surgeon and former president of the British Orthopaedic Association, stated that there may be certain "direct anti-inflammatory effects and possible cartilage protection effects." However, he urged caution, emphasizing that the results do not demonstrate that these medications eliminate the need for surgical intervention.