A rapid and sustained improvement of calcification propensity score (serum T 50 ) after successful kidney transplantation: Reanalysis of a randomized controlled trial of ibandronate

Clin Transplant. 2017 Dec;31(12). doi: 10.1111/ctr.13131. Epub 2017 Oct 26.


A serum test called T50 assesses the overall propensity for calcification of the blood and is associated with cardiovascular outcomes. We aimed to examine T50 over time in kidney transplant recipients and also address any effects of ibandronate. Serum samples taken from kidney transplant patients included in a prospective, randomized placebo controlled study of ibandronate were analyzed in retrospect. Adequate analyses were performed at baseline (approximately 3 weeks after transplantation) in 129 patients, at 10 weeks in 127 patients and at 1 year in 123 patients. There were no statistical differences between ibandronate and placebo treatment in terms of T50 at 10 weeks (P = .094) or at 1 year (P = .116). Baseline T50 was a significant covariate (P < .0001) for T50 scores at 10 weeks and 1 year. In the total cohort, there was a highly significant (P < .0001) increase in T50 of 26.6% after 10 weeks and T50 remained stable after 1 year. T50 change was inversely correlated to phosphate of -0.515 (P < .0001) and to change in serum albumin (P < .03). We found that T50 increased from baseline to 10 weeks after transplantation with no further change after 1 year. Ibandronate had no effect on T50 .

Keywords: 1-year longitudinal randomized placebo-controlled clinical trial; calcification propensity score T50; ibandronate; kidney transplantation.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Bone Density Conservation Agents / therapeutic use*
  • Calcinosis / drug therapy*
  • Calcinosis / epidemiology
  • Diphosphonates / therapeutic use*
  • Female
  • Follow-Up Studies
  • Glomerular Filtration Rate
  • Graft Survival / drug effects*
  • Humans
  • Ibandronic Acid
  • Kidney Failure, Chronic / surgery*
  • Kidney Function Tests
  • Kidney Transplantation / methods*
  • Male
  • Middle Aged
  • Norway / epidemiology
  • Prognosis
  • Propensity Score*
  • Prospective Studies
  • Risk Factors


  • Bone Density Conservation Agents
  • Diphosphonates
  • Ibandronic Acid