Calcitriol per os Once, Twice or Three Times a Week: Effect of Different Schedules of Administration in Hemodialysis Patients

Abstract

Administration of a single dose of 1,25-OH₂D₃ can lower PTH levels for up to 4 days in chronic hemodialysis patients. Our purpose was to verify the effects of the same weekly dose of calcitriol per os given in one, two or three administrations, to patients on dialysis with secondary hyperparathyroidism. Thirty patients were studied, divided in to three groups each of 10 patients. Calcitriol therapy in group A was given as a single weekly dose of 0.08 µg/kg b.w. In group B the same total weekly dose was divided in two equal doses. In group C the same total weekly dose was divided in three times. Treatment lastet 2 months. After 8 weeks of therapy the fall in intact PTH was statistically significant in each group, respectively with one-way ANOVA: p < 0.02 (A); p < 0.002 (B); p < 0.001 (c). Two-way ANOVA for comparison of PTH % variation among the three groups was statistically significant p < 0.003. Significance was due to difference between group A and groups B and C. The present study confirms the efficacy of single dose in suppressing significantly intact PTH. However, when the same weekly dose is divided into two or in three time-spaced administrations, the suppressive effects are definitely increased.