Vascular endothelial cell function and cardiovascular risk factors in patients with chronic renal failure

Abstract

Cardiovascular risk factors and markers of endothelial cell function were studied in nondiabetic patients with mild to moderate chronic renal failure. The transcapillary escape rate of albumin and the plasma concentrations of von Willebrand factor, fibrinogen, and plasma lipids were measured in 29 nondiabetic patients (GFR of 25 (11-44) mL/min x 1.73 m2 (median and range)) and 14 normal subjects. The proportion of smokers was similar between the groups. In the patients, the plasma concentration of von Willebrand factor was elevated by 61% (1.27 ± 0.44 versus 0.79 ± 0.28 U/mL; P < 0.01) (mean ± SD) and that of fibrinogen was elevated by 72% (10.18 ± 4.14 versus 5.92 ± 2.01 μmol/L; P < 0.01). The plasma concentrations of lipoproteins showed an atherogenic pattern in the patients with increased levels of very low-density lipoprotein cholesterol (0.57 ± 0.31 versus 0.33 ± 0.13 mmol/L; P < 0.01) and triglycerides (1.26 ± 0.25 versus 0.71 ± 0.28 mmol/L; P < 0.01), but a decreased level of high-density lipoprotein cholesterol (1.23 ± 0.33 versus 1.46 ± 0.35 mmol/L; P < 0.05). Total cholesterol and low-density lipoprotein cholesterol were similar in the groups. The observed differences were further aggravated among smoking patients, particularly with respect to von Willebrand factor and triglycerides. The transcapillary escape rate of albumin was similar in the patients and the controls and was not correlated to the level of albuminuria. The combination of probable vascular injury and an elevated plasma concentration of fibrinogen may increase the risk of thrombotic episodes in the patients and, together with dyslipidemia and hypertension, may explain the increased cardiovascular morbidity and mortality in chronic nephropathy.