New Study Reveals Metformin Can Relieve Knee Osteoarthritis Pain in Overweight Patients

A promising new study published in the Journal of the American Medical Association (JAMA) indicates that metformin, a medication widely used to manage type 2 diabetes, may significantly alleviate knee pain in individuals suffering from osteoarthritis (OA) who are overweight or obese. Conducted by researchers from Monash University and supported by several medical institutions in Australia, the study explored the drug's effects on 107 overweight individuals aged over 40 who had experienced knee pain for more than six months. Participants were divided into two groups: one received up to 2,000 mg of metformin daily, while the other received a placebo. Upon completion of the six-month trial, those on metformin reported a mean reduction in knee pain of 31.3 points on a 100-point visual analog scale, compared to an 18.9-point reduction in the placebo group. Additionally, the treatment group exhibited improvements in knee stiffness and functionality, although there were no significant quality-of-life differences between the two groups. The study's lead researcher, Professor Flavia Cicuttini, emphasized the medication's potential to delay the need for invasive surgical interventions like knee replacement, which is a common recourse for patients with severe osteoarthritis. Cicuttini commented on the widespread familiarity of general practitioners (GPs) with metformin, highlighting its safety, low cost, and the fact that it could be easily integrated into current treatment regimens without requiring extensive changes or monitoring. The findings suggest that metformin could provide a valuable alternative for managing knee OA pain, especially for patients unable to tolerate typical pain-relieving medication such as NSAIDs. While the study marks a significant advancement in off-label treatment options for OA, it is important to acknowledge its limitations, primarily the relatively small sample size and duration of the study. The authors called for larger clinical trials to further validate the benefits observed. Despite the modest nature of the effect size (0.43), the results remain significant, indicating a potential shift in the treatment paradigm for knee OA—one that emphasizes medication with broader metabolic benefits. With growing concerns over rates of patient dissatisfaction with knee replacements, it may be critical for healthcare providers to explore this approach, especially given that many patients face substantial barriers in maintaining weight loss and physical activity. Though metformin is not officially approved for use in osteoarthritis patients, the findings, combined with a history of safe use and tolerated side effects, prompt a serious consideration of its role in the management of this debilitating condition. The recognition of its anti-inflammatory properties and the potential to improve knee joint health could augur a new chapter in OA management, making it essential for clinicians to stay informed on the evolving landscape of treatment options for this prevalent condition.