Effect of ergocalciferol supplementation on serum parathyroid hormone and serum 25-hydroxyvitamin D in chronic kidney disease

Aim: To assess the impact of the administration of ergocalciferol on serum parathyroid hormone levels at different stages of chronic kidney disease (CKD). Methods: A continuous series of 85 patients with stages 3-5 CKD but excluding patients on dialysis referred to the Kaiser Kidney Program were followed. Baseline serum intact parathyroid hormone (iPTH) and serum 25(OH)D levels were measured. All patients were administered ergocalciferol in doses ranging from 800 iu/day to 100 000 iu/week. We obtained serum levels of iPTH and 25(OH)D for a post-treatment endpoint after a median treatment period of 90 days. Results: Pre- and post-treatment serum iPTH levels displayed a mean difference of 2.8 pmol/L (95% Cl 1.3-4.4, P < 0.001). Patients with stage 4 CKD had a mean difference of 3.6 pmol/L (95% Cl 1.7-5.5, P < 0.001) between pre- and post-iPTH levels. Serum iPTH levels decreased among CKD stages 3 and 5, but were not statistically significant. All CKD groups analysed in the present study had significant increases in serum 25(OH)D levels. None of the study population required cessation of vitamin D therapy and no adverse outcomes were reported. Conclusion: Ergocalciferol supplementation appears a safe and effective treatment for CKD populations which may raise levels of serum 25(OH)D levels and decrease iPTH levels.