Older Korean men with inadequate vitamin D status have lower odds of radiologic osteoarthritis

Most studies on osteoarthritis (OA) and vitamin D status were performed in Whites with relatively adequate vitamin D status. Associations may differ by baseline 25-hydroxyvitamin D (25(OH)D) and race. We assessed the odds of OA and joint pain according to vitamin D status in Korean adults ≥ 50 years of age in the nationally representative Korea National Health and Nutrition Examination Survey (n = 8575). Agreement between radiologic OA (ROA) and self-reported OA were also assessed. Multivariate logistic regression was performed and participants were stratified by sex. Adults with serum 25(OH)D < 12 ng/mL and 12 to < 20 ng/mL had 26% and 18% lower odds of knee ROA, respectively, compared to those with 25(OH)D ≥ 20 ng/mL. Similar results were observed in men, but not women. No associations were found between 25(OH)D and knee ROA severity, lumbar spine ROA, symptomatic OA, or knee pain. Sensitivity of self-reported OA was low (27%), indicating a weak possibility of reverse causation. Prospective studies are required to identify the possible causality of vitamin D on OA in Korean men.