Patients with chronic kidney disease (CKD) have a higher mortality rate than the general
population, with cardiovascular disease (CVD) accounting for approximately 50% of deaths.
Vascular calcification is a common finding in patients with CKD. Furthermore, patients with
CKD develop secondary hyperparathyroidism, partly because of a decrease of calcitriol
synthesis on the kidney. Treatment of secondary hyperparathyroidism includes use of activated
vitamin D including calcitriol and paricalcitol. Recent evidence in dialysis patients suggest
an improved survival in patients using paricalcitol compared to calcitriol.
Studies in uremic rats suggests that there are differential effects of calcitriol and
paricalcitol in expression of markers of soft-tissue calcification independent of
calcium-phosphorus product. Calcitriol increased calcification of vascular smooth muscle
cells cultured in calcification media. There was also significant increase in pulse pressure
in animals treated with calcitriol.
The investigators hypothesize that these different forms of vitamin D may have differential
effects in vascular calcification progression in CKD patients.