TY - JOUR
T1 - Associations of total and free 25OHD and 1,25(OH)2D with serum markers of inflammation in older men
AU - Srikanth, P.
AU - Chun, R. F.
AU - Hewison, M.
AU - Adams, J. S.
AU - Bouillon, R.
AU - Vanderschueren, D.
AU - Lane, N.
AU - Cawthon, P. M.
AU - Dam, T.
AU - Barrett-Connor, E.
AU - Daniels, L. B.
AU - Shikany, J. M.
AU - Stefanick, M. L.
AU - Cauley, J. A.
AU - Orwoll, E. S.
AU - Nielson, C. M.
PY - 2016/7/1
Y1 - 2016/7/1
N2 - Summary: Vitamin 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. Introduction: Vitamin 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. Methods: We 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. Results: IL-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). Conclusions: Associations 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.
AB - Summary: Vitamin 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. Introduction: Vitamin 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. Methods: We 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. Results: IL-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). Conclusions: Associations 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.
KW - Elderly
KW - Free 1,25(OH)D
KW - Free 25OHD
KW - Inflammation
KW - Men
KW - Total 1,25(OH)D
KW - Total 25OHD
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U2 - 10.1007/s00198-016-3537-3
DO - 10.1007/s00198-016-3537-3
M3 - Article
C2 - 26905270
AN - SCOPUS:84959120357
VL - 27
SP - 2291
EP - 2300
JO - Osteoporosis International
JF - Osteoporosis International
SN - 0937-941X
IS - 7
ER -