Certain clinical studies suggest that metformin may reduce the risk of osteoarthritis (OA) in people with type 2 diabetes. A recent study has reported an OA incidence rate of 27.5 events per 1,000 person-years and 39.6 events per 1,000 person-years in patients treated with metformin and sulfonylurea, respectively. The study has been published in the recent issue of JAMA Network Open.
Dr. Mathew Baker and colleagues conducted a retrospective study on 20,937 adults with diabetes to analyze the risk of developing OA in those receiving metformin and sulfonylurea. They found that diabetes patients receiving metformin had a 24% lower risk of developing OA (P<0.001). No significant difference in the risk of joint replacement was observed in the treatment groups (P=0.034). When compared to those on a sulfonylurea, metformin patients continued to have a lower risk of developing OA (P<0.001), although the risk of joint replacement remained non-significant (P =0.89).
A 2022 comparator study reported that metformin use was linked to a lower risk of all-cause dementia, Alzheimer’s disease, and vascular dementia, but not with Parkinson’s disease or mild cognitive impairment. During the 5-year follow-up, 3207 patients had all-cause dementia (2.3% metformin users and 5.8% sulfonylurea users), and 760 patients developed Parkinson’s disease (0.7% metformin users and 0.8% sulfonylurea users). The hazard ratios noted for Parkinson’s disease and all-cause dementia were 0.80 and 1.00, respectively. The corresponding hazard ratios noted for Alzheimer’s disease, vascular dementia, and mild cognitive impairment were 0.81, 0.79, and 0.91. In order to address the advantages and safety issues related to the repurposing of metformin, this study emphasizes the importance of carefully considering renal function, age, and race when choosing patients for clinical studies.
The exact mechanism by which metformin confers protection against OA is not yet fully understood, but it is speculated to involve the drug’s ability to reduce inflammation and oxidative stress. In light of these results, future interventional studies with metformin to treat or prevent OA might be considered; preclinical and observational data suggest that metformin may have a protective association.
References
- Baker MC, Sheth K, Liu Y, Lu D, Lu R, Robinson WH. Development of Osteoarthritis in Adults With Type 2 Diabetes Treated With Metformin vs a Sulfonylurea. JAMA Network Open. 2023 Mar 1;6(3):e233646.
- Newby D, Linden AB, Fernandes M, Molero Y, Winchester L, Sproviero W, Ghose U, Li QS, Launer LJ, van Duijn CM, Nevado-Holgado AJ. Comparative effect of metformin versus sulfonylureas with dementia and Parkinson’s disease risk in US patients over 50 with type 2 diabetes mellitus. BMJ Open Diabetes Research and Care. 2022 Sep 1;10(5):e003036.