Background: Chronic kidney disease (CKD) predisposes to accelerated atherosclerosis that is measured by carotid artery intima media thickness (CIMT) and brachial artery flow-mediated dilation (FMD). The aim of this study was to assess the noninvasive risk markers of subclinical atherosclerosis and endothelial dysfunction and their correlation with disease severity.
Methods and results: This was a cross-sectional study conducted in 62 patients with CKD: 38 predialysis and 24 on hemodialysis and 50 age- and gender-matched controls. In both the patients and controls, high-sensitivity C-reactive protein (CRP) levels, %FMD, and CIMT were measured. Patients with CKD had increased CRP levels {[5.8 (1.0-6.0)] mg/L vs [1.0 (0.5-2.20)] mg/L; P < 0.001}; %FMD was significantly lower in patients on hemodialysis (5.51%) compared with stage IV (7.62%) and stage III (15.02%) and 17.95% in control subjects (P < 0.001); and CIMT values in hemodialysis patients (0.88 ± 0.06 mm) were significantly higher compared with stage IV (0.67 ± 0.10) and stage III (0.61 ± 0.12) (P < 0.001). Increased CIMT values were seen in patients with CKD (0.82 ± 0.21 mm) than in the healthy controls (0.55 ± 0.16 mm). In patients with CKD, a significant negative correlation was found between CRP levels and FMD responses (r = -0.315; P < 0.001), while a significant positive correlation was found between CRP and CIMT values (r = 0.327; P < 0.001). Compared with predialysis, hemodialysis subjects had significantly lower FMD and higher CRP and IMT values.
Conclusion: CKD confers a higher inflammatory status when compared with apparently healthy general population. Abnormal FMD responses and CIMT values are more commonly found in dialysis patients. Our findings suggest that CIMT and FMD can be used as noninvasive markers for early risk assessment and stratification in various stages of CKD.
Keywords: Cardiovascular risk; chronic kidney disease; noninvasive risk markers; subclinical atherosclerosis.