Erythrocyte aggregation as an early biomarker in patients with asymptomatic carotid stenosis

Background: Atherosclerosis is a chronic inflammatory disease. Design: We have evaluated the degree of erythrocyte aggregation (EA) as a microinflammatory biomarker in a cohort of hospital-based, neurologically asymptomatic outpatients. Methods: The degree of EA and carotid artery stenosis was evaluated in 510 individuals by using a simple slide test and image analysis. Results: Four hundred and sixteen individuals had minimal carotid stenosis (< 30%); 47 had mild to moderate stenosis (30-69%) and 47 had severe stenosis (> 70%). A significant correlation was noted between the degree of carotid stenosis and the erythrocyte sedimentation rate (ESR), white blood cell count (WBCC) and fibrinogen (r=0.160, p=0.005; r=0.191, p=0.001 and r=0.126, p=0.026, respectively). The significant correlation was noted between the degree of carotid stenosis and EA (r=0.209, p< 0.001). The subjects with severe stenosis differed significantly from the other groups in their ESR, WBCC and EA. High sensitivity C-reactive protein (hs-CRP) concentrations did not discriminate between the presence and absence of significant carotid atherosclerotic disease. Conclusions: Inflammatory biomarkers such as ESR and the EA test are more sensitive than hs-CRP to the presence of a significant atherosclerotic carotid burden. These biomarkers might aid in the detection and quantification of microinflammation in individuals with carotid atherosclerosis.