Long-term cholecalciferol administration in hemodialysis patients: a single-center randomized pilot study.

Background: Data on the potent pleiotropic extraskeletal effects of vitamin D have renewed interest in its use in selected populations, including patients with chronic kidney disease, but the available data are still insufficient to make recommendations. This study assessed the long-term effect of small cholecalciferol doses on serum vitamin D, parathormone (PTH), and bone mineral density (BMD) in hemodialysis patients.
Material/methods: Nineteen patients with serum 25(OH)D <20 ng/mL were randomized into cholecalciferol (2000 IU 3×/week) and no-treatment groups, then observed for 1 year. Patients with hypercalcemia, hyperphosphatemia, and receiving vitamin D/calcimimetics were excluded. Serum 25(OH)D, 1,25(OH)2D, PTH, and alkaline phosphatase activity were examined every 2 months and BMD was measured before and after the study.
Results: We observed normalization of serum 25(OH)D with an increase in medians from 11.3 to 44.9 ng/mL (P=0.02) in the cholecalciferol group and no change in the controls (P<0.001). Simultaneously, median serum 1,25(OH)2D increased from 18.2 to 43.1 pmol/L (P=0.02) in the cholecalciferol group and from 10.6 to 21.2 pmol/L (P=0.02) in controls (P=0.013). The treatment was associated with a small increase in serum calcium, but serum phosphate, PTH, alkaline phosphatase, and BMD remained unchanged in both groups.
Conclusions: Oral cholecalciferol at a dose of 2000 IU/3×/week is an effective and safe way to treat vitamin D deficiency in hemodialysis patients, leading to a significant increase in serum 1,25(OH)2D. However, it was insufficient to suppress the activity of parathyroid glands or to significantly change BMD.