Abstract 643: Lower Levels of Circulating Endothelial Progenitor Cells is Associated with an Increased Carotid Atherosclerosis Burden in Patients with Stroke
Introduction Circulating endothelial progenitor cells (CEPCs) play a crucial role in ongoing endothelial repair. Impairment in mobilization or depletion of CEPCs may lead to endothelial dysfunction & progression of atherosclerosis. We hypothesized that a low level of CEPCs contributes to progression of carotid atherosclerosis.
Methods We measured the number of CEPCs in 30 patients (pts) with stable ischemic stroke & in 29 age-sex matched controls (62±2 years; 66% males). CEPC count was determined by the number of CD34 and KDR positive cells using flow cytometry. Carotid atherosclerosis was assessed by measuring carotid artery intima-media thickness (IMT) using vascular ultrasound.
Results There were no significant differences in age, sex and prevalence of smoking & hyperlipidemia between stroke pts & controls. Stroke pts had a significantly lower number of CEPCs compared with controls (27.1±2.5 vs 50.2±5.6/μl, p<0.05). There was a significant inverse correlation between IMT & number of CEPCs (r= −0.39, Fig. 1⇓). Stroke pts were divided into high (n=17) or low CEPC count (n=13) groups using a cutoff value of 20.3/μl (25th percentile of control CEPC count). There were no significant differences in age, sex & prevalence of hypertension, smoking, hyperlipidemia & diabetes between stroke pts with low & high CEPC counts. However, the mean max IMT and max IMT were significantly higher in stroke pts with low CEPC count as compared to stroke pts with high CEPC count (Fig. 2⇓).
Conclusions Pts with stable ischemic stroke have decreased number of CEPCs as compared with controls. Furthermore, in pts with stroke, a lower level of CEPCs is associated with a greater degree of carotid atherosclerosis.