CLINICAL IMPORTANCE OF MARKERS OF RENAL DYSFUNCTION IN CARDIO-VASCULAR RISK STRATIFICATION

Abstract

Purpose of the study. To study the significance of cystatin C of blood plasma and its relationship with central arterial pressure and carotid intima-media thickness (CIMT) in the stratification of cardiovascular risk.Materials and methods. A general clinical and laboratory examination of 206 patients aged 16 to 88 years was performed, of which men were 101 (49%), women - 105 (51%). The mean age of the examined subjects was 51.8±14.3 years. Lipid spectrum parameters [total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C)], cystatin C, plasma uric acid and fibrinogen were studied. Glomerular filtration rate (GFR) was calculated using the F.J. Hoek et al. (2003) formula. To assess the central blood pressure, all patients underwent a contour analysis of the pulse wave on the AngioScan-01 (AngioScan-Electronics, Russia) and ultrasound examination of carotid artery (CA) on Vivid Q (USA). The type of research was single-step cross-sectional. Depending on the content of cystatin C of the blood plasma, all the examined subjects were divided into three groups. Group 1 (n=62) consisted of patients with cystatin C concentration of up to 0.99 mg/l; group 2 (n=91) - from 1.0 mg/l to 1.5 mg/l; group 3 (n=53) - over 1.51 mg/l.Results. Patients with excessive body weight, stable angina, type 2 diabetes, cerebrovascular diseases (CVD) and chronic glomerulonephritis (CGN) significantly prevailed in group 3, in comparison with groups 1 and 2 (p<0.5). Mean levels of systolic and central blood pressure (BP) were significantly higher in patients from group 3 (p<0.05). In the same group, there was a significant decrease in HDL cholesterol level (p<0.05), an increase in TG concentration (p<0.05), and blood plasma uric acid (p<0.05), as well as CIMT. Statistically and clinically significant decrease in GFR and an increase in the level of cystatin C in blood plasma was noted both in groups 2 and 3 (p<0.05). Positive correlation between CIMT and the level of cystatin C of blood plasma (r=0.578, p<0.05) and negative correlation with the value of GFR (r=-0.556, p<0.05) were recorded among the patients of group 1. In group 2, strong correlation was observed between CIMT and the content of HDL cholesterol plasma (r=-0.343; p<0.05). A significant direct relationship between CIMT and systolic level (r=0.482, p<0.05) and central arterial pressure (r=0.479, p<0.05) was found in individuals from group 3.Conclusion. Studying the content of cystatin C of blood plasma in conjunction with determination of GFR is a priority for early diagnosis of renal dysfunction and assessment of cardiovascular disorders, providing stratification of groups of cardiovascular risk and subsequent implementation of preventive measures to reduce the level of total cardiovascular risk.