Longitudinal increase in vitamin D binding protein levels after initiation of tenofovir/lamivudine/efavirenz among individuals with HIV.

ABSTRACT: OBJECTIVETo examine longitudinal change in vitamin D binding protein (DBP) levels during the first year after initiation of tenofovir disoproxil fumarate (TDF)/lamivudine/efavirenz and compare these findings with concurrent changes in markers of skeletal metabolism.DESIGNSecondary analysis of plasma samples collected from an ongoing multicenter clinical trial.METHODSPlasma samples collected at 0, 24, and 48 weeks after initiation of TDF?+?lamivudine?+?efavirenz from 134 adult participants enrolled in a multicenter randomized trial were analyzed. Data regarding sociodemographic and clinical characteristics were obtained as part of the parent study. Laboratory analyses included plasma DBP, intact parathyroid hormone, total 25-hydroxy vitamin D, phosphorus, the bone resorption marker collagen type 1 cross-linked C-telopeptide, and the bone formation marker total procollagen type 1 N-terminal propeptide. Repeated measures analysis of variance was used to measure changes in biomarkers over time.RESULTSOur sample included 108 men and 26 women (mean age 33.6?±?9.6 years). Median levels of DBP increased significantly from baseline to 48 weeks [154 (91.8-257.4) versus 198.3 (119.6-351.9)??g/ml, P?CONCLUSIONOur study provides longitudinal data supporting a potential role for DBP in bone loss associated with TDF-based therapy. Further research to elucidate the mechanistic pathways and clinical impact of these findings is warranted.

SUBMITTER: Hsieh E 

PROVIDER: S-EPMC4949136 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature