25-hydroxyvitamin D Serum Level and Risk of Knee Osteoarthritis in the Elderly

Abstract

Background: Osteoarthritis (OA) is a degenerative joint disease that commonly affects the elderly, particularly in the knees. It may lead to chronic pain, physical limitations, depression, and significantly impact an individual’s ability to participate in social, occupational, and community activities, ultimately reducing quality of life. Vitamin D has been suggested as a factor that may help reduce the risk of knee OA in older adults. This study aimed to investigate the relationship between serum 25-hydroxyvitamin D levels and the risk of knee OA among the elderly. Methods: This cross-sectional study involved elderly residents of a nursing home in North Jakarta, Indonesia. Data was collected through interviews and physical examinations of both knees following the American Rheumatism Knee OA diagnostic criteria. Participants who met these criteria were classified as high-risk for knee OA. Blood samples were analyzed for 25-hydroxyvitamin D (25(OH)D) levels using an enzyme-linked immunosorbent assay (ELISA). Bivariate analysis was performed using the Chi-square test. Results: Of the 48 participants, the majority were female (64.6%) and aged 70–79 years (47.9%). A total of 22.9% of participants were classified as 25(OH)D insufficient and 25% were deficient. Interestingly, 62.5% were at high risk of knee OA. There was a significant association between 25(OH)D levels and the risk of knee OA (p=0.031). Conclusions: Serum 25(OH)D levels are significantly associated with the risk of knee OA in the elderly. Promoting daily outdoor activities and considering vitamin D supplementation may help reduce the risk of knee OA and improve bone health in this population.