P4.23 CORRECTION OF VITAMIN D DEFICIENCY BY CALCIFEDIOL IN HYPERTENSIVES WITH STAGE 3 CHRONIC KIDNEY DISEASE REDUCES PULSE WAVE VELOCITY BY LOWERING BLOOD PRESSURE

Abstract

Objectives: To measure the extent of correction of vitamin D deficiency and hyperparathyroidism after treatment with calcifediol as well as their relationship to blood pressure and arterial stiffness in hypertensive patients with stage 3 chronic kidney disease (CKD). Methods: Longitudinal study that included 74 treated hypertensives (46 women, 62,2%) with stage 3 CKD (eGFR 47,7 ml/min, SD±10) without previous vitamin D supplementation treatment. Calcifediol 266 μg/2 weeks and calcium 600 mg/d were given if baseline-vitamin D < 30 ng/ml and < 9,5 mmol/l, respectively. A second visit took place after 4 months. Results: The mean age was 72,9 years (SD±10). The prevalence of vitamin D deficiency decreased from initially 96% to 23% (mean baseline: 18, mean final: 42 ng/ml), and of secondary hyperparathytoidism from 62% to 37% (mean at baseline: 87, mean final: 63 pg/ml). There were no significant changes in eGFR, calcium or phosphor or number of antihypertensive drugs, but pulse wave velocity (measured with MOBILOGRAPH®) and BP decreased significantly form initially 133/76 to 123/72 (p<0.001) mmHg and from 10,8 to 10,5 m/sec (p<0.005), respectively. In bivariate analysis the difference between baseline and final vitamin D and PTH correlated significantly. The only variable significantly related to the change in PWV was the difference in peripheral SBP. Only one case of asymptomatic hypercalcemia was observed. Conclusions: In hypertensive patients with stage 3 CKD, correction of vitamin D deficiency by oral caldifediol leads to a substantial reduction of incipient hyperparathyroidism and a significant decrease of arterial stiffness.