Correlation Between Vitamin D and Degenerative Joint Disorders: Review and Meta-Analysis

Abstract

Objective: Evaluate the evidence of the clinical correlation between vitamin D and symptomatic degenerative joint disease. Methods: A systematic search and meta-analysis was conducted of randomized controlled studies (RCTs) published in between January 1st, 2010, and March 30th, 2020 on five different databases. The study population consisted of adult patients with symptomatic knee osteoarthritis; the intervention was vitamin D; the comparison was placebo, and the outcomes included the Western Ontario and McMaster Universities Arthritis Index (WOMAC) (pain, function, stiffness), tibial cartilage volume, synovial tissue volume (STV), subchondral bone marrow lesion (BML) volume, effusion-synovitis, serum vitamin D3 levels, serological inflammatory and metabolic biomarkers levels and adverse events. Results: Nine RCTs involving 2,168 patients were included in this study. Pooled estimates suggested that vitamin D supplementation was associated with reduction in WOMAC pain (Std. Mean=1.08(0.90, 1.25); I2=99%; p=0.00001), function (Mean=1.1(0.92, 1.27); I2=99%; p=0.00001), stiffness (Std. mean= 0.72(0.54, 0.90); I2=98%; p=0.00001) and synovial effusion in the suprapatellar pouch numbers. There was no significant difference in tibial cartilage volume incidence (Std. Mean=0.26(0.44, 0.80); I2=99%; p=0.00001), STV, BML volume, inflammatory biomarkers and adverse events between the vitamin D and the placebo groups. Conclusion: Vitamin D supplementation was effective in improving WOMAC pain and function in patients with knee OA and also improved serological vitamin D levels. However, it had no beneficial effect on structural cartilage change or inflammatory biomarker reduction. Therefore, there is currently a lack of evidence on vitamin D regimen dosage and length to obtain benefits in preventing knee disease progression.