How Vitamin D Analogues Affect Endothelial Cells in Patients on Dialysis

Effect of Doxercalciferol on Endothelial Cell Function in End Stage Renal Disease

Patients with chronic kidney disease and end stage renal disease have greater cardiovascular risk than the general population. Vitamin D analogues have been shown in observational studies to have mortality benefit for these patients. This study is designed to investigate doxercalciferol's effect on the vasculature (i.e. endothelial cell function) as a possible mechanism to explain the mortality benefit.

Inclusion Criteria:

• Stage 5 Chronic Kidney Disease
• Hyperparathyroidism (PTH>300) requiring vitamin D therapy
• Age 18-80 years old
• Ability to provide informed consent

Exclusion Criteria:

• Subjects with neovascularization present, such as neoplasm, active wounds or significant retinopathy
• Subjects with contraindications or allergy to vitamin D
• Subjects currently on vitamin D therapy or a history of vitamin D therapy in the previous 60 days
• Serum phosphorus > 6
• Serum calcium > 10.5
• contraindications to nitroglycerin (such as being on sildenafil)