Cardiovascular disease reduces life expectancy by 40-60 years in children on dialysis. An important cause is derangement of the hormones PTH and vitamin D that control calcium absorption and its incorporation into bone. Abnormal PTH or vitamin D levels can cause ‘furring up’ or hardening of arteries and brittle bones. Current practise is based on PTH control, but we now know that vitamin D plays an equal, if not more important, role and also has direct protective effects on the heart and blood vessels.

In a future longitudinal follow-up study we would like to determine the effects of maintaining normal vitamin D levels in advanced kidney disease and determine if this is associated with less vascular damage and calcification than with conventional management by manipulation of PTH levels alone. However, in order to test this hypothesis we need 2 pilot studies at this stage. For the current project we propose the following:

Part 1: to test the feasibility and safety of maintaining normal Vitamin D levels by careful titration of the vitamin D dosage  

Part 2: measuring the rate of progression of vascular changes (measured by ultrasound based methods) and calcification (as seen on CT scan) in children with advanced kidney disease.