title: Effect of paricalcitol vs calcitriol on hemoglobin levels in chronic kidney disease patients: a randomized trial.
abstract: BACKGROUND
  Recent studies suggest that vitamin D deficiency represents an additional cofactor of renal anemia, with several mechanisms accounting for this relationship. In line with it, the administration of vitamin D or its analogues has been associated with an improvement of anemia. There are no data, however, about a direct effect of paricalcitol on hemoglobin (Hb) levels. Therefore, we conducted a study to determine whether paricalcitol, compared to calcitriol, improves anemia in patients with chronic kidney disease (CKD).
  
  
  METHODS
  In this randomized trial 60 CKD patients stage 3b-5 and anemia (Hb levels: 10-12.5 g/dL) were assigned (1:1) to receive low doses of calcitriol (Group Calcitriol) or paricalcitol (Group Paricalcitol) for 6 months. All the patients had normal values of plasma calcium, phosphorus and PTH, a stable iron balance, and normal values of C-Reactive Protein. The primary endpoint was to evaluate the effects of the two treatments on Hb levels; the modifications in 24hr-proteinuria (UProt) were also evaluated.
  
  
  RESULTS
  A significant Group x Time interaction effect was observed in the longitudinal analysis of Hb levels (F(1,172)=31.4, p<0.001). Subjects in Paricalcitol experienced a significant monthly increase of Hb levels equal to +0.16 g/dL [95% C.I. 0.10 to +0.22, p<0.001) while in Group Calcitriol, Hb decrease throughout the follow-up with an average monthly rate of -0.10 g/dL (95% C.I.: -0.17 to -0.04, p<0.001). In Group Paricalcitol, UProt was significantly reduced after 6 months [0.35 (0.1-1.2) vs 0.59 (0.2-1.6), p<0.01], whereas no significant difference emerged in Group Calcitriol. Plasma levels of calcium, phosphate, PTH and of inflammation markers remained in the normal range in both groups throughout the study.
  
  
  CONCLUSIONS
  Short-term exposure to paricalcitol results in an independent increase in Hb levels, which occurred with no modification of iron balance, inflammatory markers, and PTH plasma concentrations, and was associated with a decrease in UProt.
  
  
  BACKGROUND
  ClinicalTrials.gov NCT01768351.
authors.affiliation: Chair of Nephrology, Department of Public Health, University Federico II of Naples, Naples, Italy.
authors.forename: Eleonora
authors.initials: E
authors.lastname: Riccio
authors.affiliation: Chair of Nephrology, Department of Public Health, University Federico II of Naples, Naples, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Sabbatini
authors.affiliation: Chair of Statistics, Department of Public Health, University Federico II of Naples, Naples, Italy.
authors.forename: Dario
authors.initials: D
authors.lastname: Bruzzese
authors.affiliation: Chair of Nephrology, Department of Public Health, University Federico II of Naples, Naples, Italy.
authors.forename: Ivana
authors.initials: I
authors.lastname: Capuano
authors.affiliation: Chair of Nephrology, Department of Public Health, University Federico II of Naples, Naples, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Migliaccio
authors.affiliation: Unit of Nephrology, University Magna Graecia, Catanzaro, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Andreucci
authors.affiliation: Chair of Nephrology, Department of Public Health, University Federico II of Naples, Naples, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Pisani
mesh_terms: D002097:C-Reactive Protein / Q000378:metabolism; D002117:Calcitriol / Q000494:pharmacology* / Q000627:therapeutic use; D004872:Ergocalciferols / Q000494:pharmacology* / Q000627:therapeutic use; D005260:Female; D005500:Follow-Up Studies; D006454:Hemoglobins / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D051436:Renal Insufficiency, Chronic / Q000188:drug therapy* / Q000378:metabolism*; D016896:Treatment Outcome
chemical_list: D004872:Ergocalciferols; D006454:Hemoglobins; C084656:paricalcitol; D002097:C-Reactive Protein; D002117:Calcitriol