Dynamics of cardiovascular risk factors in patients with obstructive sleep apnoe syndrom undergoing CPAP-therapy

The aim of the study was to investigate the intensity of a number of risk factors resulting in cardiovascular complications, such as body mass index (BMI), level of mean arterial pressure (MAP), left ventricular mass index (LVMI), left ventricular ejection fraction (LVEF) and also ECG data (heart rate variability and ventricular ectopic activity) depending on the severity of obstructive respiratory disturbances during sleep. 76 patients with obstructive sleep apnea syndrome (OSAS) were included in the study. 38 patients with a severe form of OSAS underwent prolonged apparatus treatment which included generating positive pressure in their upper airways. After 4-month treatment the patients of this group underwent another examination to estimate all the parameters studied. Examination of patients with OSAS revealed that a number of indices (BMI, LVMI and MAP) showing the intensity of basic modified cardiovascular risk factors, such as obesity and arterial hypertension, correlate to the level of obstructive respiratory disturbances during sleep, which was estimated according to apnea-hypopnea index (AHI). Twenty-four-hour ECG monitoring of patients with OSAS showed a tendency for a decrease in heart rate variability and an increase in ventricular ectopic activity in patients with more apparent obstructive respiratory disturbances during sleep and with negative disease dynamics against the background of CPAP therapy.