Purpose of review: Apart from regulating mineral metabolism, recent evidence suggests that both the 'active' 1,25(OH)2D and the 'storage' 25(OH)D forms of vitamin D have distinct and important actions on many organ systems, bringing to light the systemic importance of both forms of the vitamin. This review discusses the current evidence related to the etiology and consequences of reduced levels of both 25(OH)D and 1,25(OH)2D in the chronic kidney disease population.
Recent findings: Both 25(OH)vitamin D and 1,25(OH)2vitamin D therapy have actions on parathyroid gland, cardiac, bone, and immune system function. In both the general and chronic kidney disease populations, vitamin D therapy decreases fracture rates, decreases cancer and infection rates, and improves cardiac function.
Summary: To improve quality of life and to decrease mortality, therapy with vitamin D - in both the 25(OH)D and 1,25(OH)2D forms - should be considered throughout the course of chronic kidney disease.