Paricalcitol supplementation during the first year after kidney transplantation does not affect calcification propensity score

BACKGROUND: Cardiovascular complications are common in kidney transplant patients and calcification propensity of blood, measured as T(50), is associated with cardiovascular outcomes. Paricalcitol supplementation affects calcium/phosphate homeostasis and may affect calcification propensity. To assess this hypothesis we measured T(50) in kidney transplant recipients participating in a randomized study comparing paricalcitol versus no treatment during the first year after kidney transplantation. METHODS: Stored serum samples from 76 kidney transplant recipients (paricalcitol n = 37, no treatment n = 39) were analyzed. Analyses were performed at inclusion (8 weeks after transplantation) and repeated one year after transplantation. RESULTS: There were no statistically significant differences in T(50) between the paricalcitol and placebo groups, neither at baseline (p = 0.56) nor at 1 year (p = 0.61). Also, there were no significant changes in T(50) over time in either group or when pooling all data (p < 0.20). In multivariate regression analysis, out of 16 potentially relevant covariates, comprising clinical and biochemical parameters, only plasma PTH and T(50) at baseline were significantly correlated to T(50) after one year. (p < 0.03 and p < 0.01, respectively). CONCLUSIONS: Calcium propensity measured as T(50) score remained unchanged with paricalcitol treatment in kidney transplant recipients, and was not changed over time during the study period of one year. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01694160, registered 23 September 2012.