Serum 25-Hydroxyvitamin D and Osteoarthritis in Older People: The Progetto Veneto Anziani Study.

Recent work has shown that low 25-hydroxyvitamin D (25OHD) levels are associated with the presence of osteoarthritis (OA), but these studies focused on radiographical changes of OA, investigated only one joint, and did not consider the association with OA-related pain. In this study, we aimed to examine the relationship between 25OHD levels and any presence of OA and pain in a cohort of older people. This study was part of the Progetto Veneto Anziani (Pro.V.A), a population-based cohort study in older people. In this cross-sectional work, we considered 2756 subjects (1102 males and 1654 females) with a mean age of 74.2 ± 7.1 years. OA and OA-related pain were defined using a standardized algorithm investigating disease history, medical documentation, symptoms, and physical examination of the joints. On logistic regression analysis, taking those in the highest 25OHD quartile for reference, those in the lowest quartile had significantly higher odds of OA involving the hands (odds ratio [OR] = 1.26, 95% confidence interval [CI] 1.15-1.38 in the sample as whole; 1.36, 95% CI 1.15-1.60 in men and 1.22, 95% CI 1.09-1.37 in women), and pain (OR = 1.18, 95% CI 1.06-1.32 in the sample as whole; 1.52, 95% CI 1.21-1.90 in men and 1.15, 95% CI 1.03-1.29 in women). Similar results were found for the hip. For the knee, low 25OHD levels were associated with the presence of OA in the sample as a whole, and in women, and with the presence of pain in the sample as a whole. In conclusion, low 25OHD levels are associated with the presence of OA and with OA-related pain, particularly when the hand and hip are involved.