Work

Baseline 25-hydroxyvitamin D levels predict the effects of vitamin D supplementation on joint symptoms and cartilage loss in patients with knee osteoarthritis

Year: 2025

Type: article

Abstract: Objectives To examine whether the baseline vitamin D level modifies the effects of vitamin D supplementation on knee symptoms and cartilage loss in patients with symptomatic knee OA. Methods This was a post hoc analysis for the VIDEO study, which was a large (n = 413), randomized, double-blind, placebo-controlled clinical trial in knee OA patients with 25-hydroxyvitamin D [25(OH)D levels ranging from 12.5 to 60 nmol/l]. Knee pain was assessed using the WOMAC pain scale. MRI scans of the knee were obtained. Cartilage volume, cartilage defects (0–4) and bone marrow lesions were measured or graded. Classification trees were applied to categorize the subgroups. Results A total of 413 participants (mean age 63.2 years; 50% women) were randomly assigned to vitamin D and placebo groups. A baseline 25(OH)D level of 43 nmol/l was found as the cut-off value. For the total WOMAC score, vitamin D supplementation decreased more than placebo in patients with 25(OH)D levels of 12.5–43 nmol/l (−256.41 vs −72.10, P = 0.0060) over 2 years but not in those with 25(OH)D levels of 43–60 nmol/l. Comparatively, vitamin D supplementation reduced the total cartilage volume loss (−0.21 vs −0.31, P = 0.0415) and total cartilage defects progression (0.26 vs 0.92, P = 0.0029) in patients with 25(OH)D levels of 43–60 nmol/l but not in those with 25(OH)D of 12.5–43 nmol/l. Conclusion Supplementation of vitamin D in patients with OA who have 25(OH)D levels ≤43 nmol/l could relieve pain and improve physical function, while in OA patients with 25(OH)D levels >43 nmol/l, supplementation may ameliorate cartilage lesions. Trial registration clinicaltrials.gov, NCT01176344; anzctr.org.au, ACTRN12610000495022

Source: Rheumatology Advances in Practice

DOI: 10.1093/rap/rkaf061