Vitamin D Supplementation Did Not Benefit Patients with Knee Osteoarthritis

As osteoarthritis affects bone turnover and cartilage deterioration, vitamin D supplementation has biological plausibility for alleviating pain and improving function. Epidemiologic and observational studies have indicated potential benefit, although trials have yielded conflicting results. Researchers in Australia conducted a trial involving 413 vitamin D–deficient but otherwise healthy participants (mean age, 63; mean 25-hydroxyvitamin D levels, 18 ng/mL) with symptomatic knee osteoarthritis. Participants were randomized to receive oral supplementation with vitamin D₃ (cholecalciferol; 50,000 IU monthly) or placebo for 24 months. Pain was assessed with a validated scale for knee osteoarthritis; cartilage volume and defects and bone marrow…