1. Associations of total and free 25OHD and 1,25(OH)2D with serum markers of inflammation in older men
- Author
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Srikanth, P, Chun, RF, Hewison, M, Adams, JS, Bouillon, R, Vanderschueren, D, Lane, N, Cawthon, PM, Dam, T, Barrett-Connor, E, Daniels, LB, Shikany, JM, Stefanick, ML, Cauley, JA, Orwoll, ES, Nielson, CM, and for the Osteoporotic Fractures in Men (MrOS) Study Research Group
- Subjects
Biomedical and Clinical Sciences ,Nutrition and Dietetics ,Inflammatory and immune system ,Aged ,Aged ,80 and over ,Biomarkers ,Humans ,Inflammation ,Interleukin-6 ,Male ,Receptors ,Tumor Necrosis Factor ,Vitamin D ,Elderly ,Free 1 ,25(OH)(2)D ,Free 25OHD ,Men ,Total 1 ,25(OH)(2)D ,Total 25OHD ,Osteoporotic Fractures in Men (MrOS) Study Research Group ,Free 1 ,25(OH)2D ,Total 1 ,25(OH)2D ,Biomedical Engineering ,Clinical Sciences ,Public Health and Health Services ,Endocrinology & Metabolism ,Clinical sciences ,Epidemiology - Abstract
UnlabelledVitamin D is hypothesized to suppress inflammation. We tested total and free vitamin D metabolites and their association with inflammatory markers. Interleukin-6 levels were lower with higher 25-hydroxyvitamin D. 1,25-dihydroxyvitamin D and free 25OHD associations mirrored those of 25OHD. However, associations for the two metabolites diverged for tumor necrosis factor alpha (TNF-α) soluble receptors.IntroductionVitamin D is hypothesized to suppress inflammation, and circulating 25-hydroxyvitamin D (25OHD) and inflammatory markers are inversely correlated. However, total serum 25OHD may not be the best indicator of biologically active vitamin D.MethodsWe tested serum total 25OHD, total 1,25(OH)2D, vitamin D binding protein (DBP), and estimated free 25OHD and free 1,25(OH)2D associations with inflammatory markers serum interleukin-6 (IL-6), TNF-α and their soluble receptors, interleukin-10 (IL-10), and C-reactive protein (CRP) as continuous outcomes and the presence of ≥2 inflammatory markers in the highest quartile as a dichotomous outcome, in a random subcohort of 679 men in the Osteoporotic Fractures in Men (MrOS) study.ResultsIL-6 was lower in men with higher 25OHD (-0.23 μg/mL per standard deviation (SD) increase in 25OHD, 95 % confidence intervals (CI) -0.07 to -0.38 μg/mL) and with higher 1,25(OH)2D (-0.20 μg/mL, 95 % CI -0.0004 to -0.39 μg/mL); free D associations were slightly stronger. 25OHD and DBP, but not 1,25(OH)2D, were independently associated with IL-6. TNF-α soluble receptors were inversely associated with 1,25(OH)2D but positively associated with 25OHD, and each had independent effects. The strongest association with ≥2 inflammatory markers in the highest quartile was for free 1,25(OH)2D (odds ratios (OR) 0.70, 95 % CI 0.54 to 0.89 per SD increase in free 1,25(OH)2D).ConclusionsAssociations of 1,25(OH)2D and free 25OHD with IL-6 mirrored those of 25OHD, suggesting that 1,25(OH)2D and free D do not improve upon 25OHD in population-based IL-6 studies. However, associations for the two metabolites diverged for TNF-α soluble receptor, warranting examination of both metabolites in studies of TNF-α and its antagonists.
- Published
- 2016