Circulating 25‐hydroxyvitamin‐D [25(OH)D] and inflammation in older community‐dwelling adults

Vitamin Ds immunoregulatory function suggests vitamin D status would be associated with inflammation status. Using factor analysis we extracted 2 principal components from 12 inflammatory markers measured in 366 adults (70–89 years, 68% female) and calculated partial Spearman correlations between plasma 25(OH)D (mean±SD = 52±26 nmol/L) and both factors and each individual marker, adjusted for age, sex, race, clinic, BMI, season, smoking, CVD, diabetes, and statin use. Factor 1 (CRP, adiponectin, IL6, IL15, IL1ra, IL1sr) was inversely correlated with 25(OH)D, but statistical significance was not reached (r= −0.10, p=0.06). Factor 2 (sTNFR1, sTNFR2, IL6sr, IL2sr, IL8, TNFα) was not correlated with 25(OH)D (r=0.03, p=0.52). Using a Bonferroni‐adjusted p<0.004, 25(OH)D was correlated with interleukin‐1 receptor antagonist (IL1ra, r=−0.19, p<0.001), but with no other individual marker (all p≥0.17). While 25(OH)D was not associated with inflammation overall, the correlation between 25(OH)D and IL1ra may partially explain reported associations between vitamin D status and diseases in which IL1ra is elevated, such as autoimmune and infectious disease. [Supported by NIH U01AG22376, P30AG21332, R01AG027529]