Location: Immunity and Disease Prevention ResearchTitle: Vitamin D3 decreases parathyroid hormone in HIV-infected youth being treated with tenofovir: a randomized, placebo-controlled trial Author
|Van Loan, Marta|
Submitted to: Clinical Infectious Diseases
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/22/2011
Publication Date: 4/1/2012
Citation: Havens, P.L., Stephensen, C.B., Hazra, R., Flynn, P.M., Wilson, C.M., Rutledge, B., Bethel, J., Pan, C.G., Woodhouse, L.R., Van Loan, M.D. 2012. Vitamin D3 decreases parathyroid hormone in HIV-infected youth being treated with tenofovir: a randomized, placebo-controlled trial. Clinical Infectious Diseases. 54(7):1013-1025. DOI: 10.1093/cid/cir968. Interpretive Summary: Young adults with HIV infection are at increased risk of vitamin D deficiency for reasons which are not clearly understood. This can adversely affect bone mineralization, which peaks in the late adolescent and young adult period. In addition, some antiretroviral drugs used to treat HIV have adverse effects on bone mineralization, perhaps by altering vitamin D metabolism. In this study we determined providing vitamin D supplementation (versus a placebo) improved vitamin D status and measures of calcium balance and bone turnover in young adults taking or not taking the antiretroviral drug tenofovir, which has known adverse effects on bone. Vitamin D improved indicators of calcium balance and, to a small degree, bone turnover in subjects taking tenofovir, suggesting that vitamin D supplementation may be a useful adjunct to routine use of tenofovir.
Technical Abstract: Objective: To determine the effect of vitamin D (VITD) supplementation on tubular reabsorption of phosphate (TRP), serum parathyroid hormone (PTH), bone alkaline phosphatase (BAP), and C telopeptide (CTX) in HIV-infected youth receiving and not receiving tenofovir-containing cART (TDF). Design: Randomized, double blind, placebo-controlled multicenter trial Methods HIV-infected youth 18-24 years, viral load <5,000 copies/mL, were enrolled based on stable treatment with cART containing TDF (N=118) or not containing TDF (noTDF; N=85). Subjects were randomized within those groups to Vitamin D3 50,000 IU (N=102) or placebo (PL; N=101) with dosing at 0, 4, and 8 weeks. Outcome measures included change in TRP, PTH, BAP, and CTX from baseline to week 12 by TDF or noTDF and by VITD or PL. Results: At baseline VITD and PL groups were similar in age, race/ethnicity, BMI, VITD status, and calcium intake. Those on TDF had lower TRP and higher PTH and CTX; but similar BAP. At week 12, 95% in VITD group had serum 25-hydroxy vitamin D (25-OHD) > 20 ng/mL, increased from 48% at baseline, with no 25-OHD change in PL (p<0.001). PTH decreased in the TDF group receiving VITD (p=0.031), but not in the noTDF group receiving VITD, or in either PL group. The decrease in PTH with VITD occurred in those on TDF with baseline 25-OHD <20 and >20 ng/mL (mean PTH change -7.9 and -6.2 pg/mL; p=0.031 and 0.053, respectively). There were no significant toxicities. Conclusion: In youth on TDF, vitamin D3 supplementation decreased PTH, regardless of baseline 25-OHD concentration.