VITAMIN D OPTIMIZING IN PATIENTS WITH CHRONIC HEART FAILURE WITH ASSESSMENT OF EFFECT ON ENDOTHELIAL FUNCTION
Objective. The aim of the study was to evaluate the effectiveness of the vitamin D deficiency/insufficiency replenishment under different dose regimens with assessment of the 25-hydroxy-vitamin D (25(OH)D) level and the endothelial function in patients with chronic heart failure (CHF).
Materials and methods. 82 patients with CHF and D-hypovitaminosis were divided into 4 groups: the patients in Group I (n=26) received cholecalciferol 2000 IU/day, in Group II (n=16) — 1000 IU/day, in Group III (n=23) — D-containing vitamin complex, in Group IV (n=17) — the basic therapy.
Results. In Group I the vitamin D levels reached the optimum in 84.6% of cases, in Group II — in 56.2% (p=0.04), in Group III — in 69.6%, in Group IV — in 29.4% of cases (p=0.0006). In Group I the nitrates/nitrites levels and the endothelium-dependent vasodilatation indices increased significantly. The regression analysis showed a positive effect of the blood vitamin D level increasing on the blood nitrates/nitrites levels increase in patients who demonstrated the vitamin D levels increasing by more than 10 ng/ml.
Conclusion. Cholecalciferol administered by 2000 IU/day was the most effective for optimizing the vitamin D level and for effecting positively on the endothelial function and the blood plasma nitrate/nitrite levels in patients with CHF.