Secondary hyperparathyroidism in chronic kidney disease: focus on clinical consequences and vitamin D therapies.

OBJECTIVE: To assess vitamin D-based treatment approaches for secondary hyperparathyroidism and its complications. DATA SOURCES: A literature search was performed using MEDLINE (1990-February 28, 2006). Key words used were chronic kidney disease and vitamin D to identify relevant papers published in English. STUDY SELECTION AND DATA EXTRACTION: From the database of articles generated, 48 papers were identified. Titles and abstracts were examined to identify those directly related to the objective. Discussion was expanded through the bibliographies of cited articles. DATA SYNTHESIS: The increasing prevalence of chronic kidney disease (CKD) in the US indicates an urgent need for treatment strategies to delay or prevent disease progression. Abnormalities in phosphorus and calcium homeostasis, vitamin D levels, and the subsequent development of secondary hyperparathyroidism (SHPT) are secondary complications of CKD associated with increased morbidity and mortality. Management options include dietary phosphorus restriction, phosphate binders and/or calcium supplementation, vitamin D supplementation, and calcimimetics. Vitamin D supplementation has received increased attention given the prevalence of vitamin D deficiency in patients with CKD and the beneficial effect of correcting this deficiency.
CONCLUSIONS: Early identification and intervention appropriate to the stage of CKD are likely to improve patient outcomes. Improved knowledge of interactions between vitamin D and vitamin D receptors has led to the development of vitamin D analogs and calcimimetics, which offer benefits in the management of SHPT. Integrating available treatment options into practice to achieve optimal therapeutic goals of SHPT based on the stage of CKD is a significant challenge for pharmacists managing patients with CKD.