Vitamin D Deficiency in Patients With Chronic Heart Failure and Morpho-Functional Condition of Peripheral Blood Erythrocytes

Abstract

The aim: To assess the vitamin D level in blood plasma of patients with chronic heart failure and to identify the effect of its deficiency on the state of peripheral blood erythrocytes during physical exertion. Materials and methods: A total of 25 patients with CHF grade IIA stages II and III functional class were examined. The control group consisted of 25 relatively healthy people. All patients were offered to complete a 6 minutes walking test. The level of 25 (OH) D total in plasma was determined by enzyme immunoanalysis. Morphological studies of erythrocytes were performed on the light-optical (Leica CME) and electron-microscopic level («JEOL-25M-T220»). Results: Patients with chronic heart failure experienced 22.9% decrease in their vitamin D level (17.2±0.04 ng/ml) compared to the control group (38.4±0.05 ng/ml). Correlation analysis showed a direct proportional relationship between vitamin D deficiency and the number of erythrocytes of a modified form (r = 0.58; p <0.05) and erythrocytes with low osmotic resistance (r = 0.87; p <0.05). During the timed physical evaluation patients who experienced chronic heart failure accompanied by vitamin D deficiency developed an increase in the number of their reversibly and irreversibly deformed erythrocytes and a decrease in the cellular osmotic tability. Conclusions: During physical exertion, patients who experienced chronic heart falure accompanied by with vitamin D deficiency experienced morpho-biochemical changes in their red blood cells. These changes indicated structural disturbances in the membranes of their erythrocytes and could potentially have negative consequences for the somatic health of these patients.