Blood pressure variability, endothelial dysfunction, and C-reactive protein levels in arterial hypertension in combination with coronary artery disease

Abstract

Background. Recently, the role of increased variability in blood pressure (BP) as a new risk factor for cardiovascular events in patients with arterial hypertension (AH) in combination with coronary heart disease (CHD) has been discussed. At the same time, the mechanisms of the participation of blood pressure variability in the development of atherosclerotic damage to the vascular wall are not well understood. Aim. To study the nature of the relationship between the indicators of daily BP variability, vasomotor function of the endothelium and highly sensetive C-reactive protein (hs-CRP) in patients with AH combined with CAD. Materials and methods. 80 patients with AH and CAD (55.50.7 years) were examined. The study assessed the BP variability according to 24-hour monitoring of BP, vasomotor function of the brachial artery endothelium, and the level hs-CRP in blood serum. Results. Increased indicators of diurnal BP variability were recorded in 48.8% of patients. There were revealed signs of endothelial dysfunction in patients in the form of a decrease in endothelium-dependent vasodilation (EDV) to 5.380.48% and an insufficient increase in endothelium-independent vasodilation (EIV) to 15.821.24%. Patients with increased variability of BP differed from patients with normal variability of BP by higher values of hs-CRP (2.980.71 and 1.560.33 mg/l; p0.05), a less pronounced response to administration nitroglycerin when evaluating EIV (13.231.79 and 17.700.77%; p0.05). Correlation relationships of variability of systolic BP (SBP) in the daytime with EVD were recorded (r=-0.44; p=0.012); variability of diastolic BP (DBP) in the daytime with EIV (r=-0.50; p=0.003); nighttime variability of DBP with EIV (r=-0.43; p=0.013). Relationships between the level of hs-CRP and the variability of SBP in the daytime (r=0.30; p=0.008) and with EVD (r=-0.47; p=0.007) were established. In patients with increased variability of SBP, the likelihood of registering an increased level of hs-CRP is 1.6 times higher OR 1.58 (95% CI 1.0142.451; p=0.043). In patients with depletion of the vasodilation reserve during the test with nitroglycerin (EIV), an increase in blood pressure variability is recorded 1.2 times more likely OR 1.22 (95% CI 1.0121.478; p=0.037). Conclusion. The revealed association of the daily variability of BP with indicators of vasomotor function of the endothelium and a marker of the inflammatory reaction of the vascular wall may indicate the presence of a pathogenetic relationship between the parameters that determine the development of adverse events in patients with AH and CAD.