Relationship between 25-hydroxy vitamin D and knee osteoarthritis: a systematic review and meta-analysis of randomized controlled trials

Wang R, et al. · Frontiers in Medicine

Pooled WOMAC pain (SMD -0.11, no heterogeneity) and function (SMD -0.88, I2 96%) improved and synovial fluid volume was lower with vitamin D; tibial cartilage volume differed in the two trials reporting it (SMD 0.18); WOMAC stiffness, joint space width and bone marrow lesions did not differ. The authors report greater benefit above 2,000 IU/day. The structural signal rests on secondary endpoints of individually null trials.

Population

Knee OA patients across 8 RCTs

Intervention

Vitamin D supplementation (various regimens)

Comparator

Placebo

Limitations

Pools trials whose primary structural endpoints were null; heterogeneity and reliance on secondary outcomes mean the pooled positives should be read cautiously. No conflicts declared.