Circulating Endothelial Cells, Arterial Stiffness, and Cardiovascular Risk Stratification in Hypertension

Abstract

Given the growing burden of cardiovascular disease, there is increasing interest in strategies to help predict future cardiovascular risk. To investigate the relationship between endothelial damage/dysfunction, arterial stiffness, and their association with predicted risk of future cardiovascular death among patients with hypertension. We studied three patient groups 35 to 74 years old: healthy control subjects (n=63), subjects with high-risk hypertension (HHT) [n=65], and patients with treated, previously diagnosed, malignant-phase hypertension (MHT) [n=43]. We measured comparative indexes of arterial stiffness (stiffness index [SI] using digital volume photoplethysmography), endothelial damage/dysfunction (venous circulating endothelial cells [CECs], immunobead technique), and 5-year predictive risk of future cardiovascular death (Pocock scoring system). CEC counts, SI, and 5-year prediction of cardiovascular death were significantly higher in both hypertension groups (HHT and MHT), compared with healthy control subjects. CEC counts were significantly higher in the MHT group (p<0.05). There was a significant correlation between CECs and SI in the HHT group (r=0.61; p<0.0001) and the MHT group (r=0.59, p<0.0001) and between CEC, SI, and predicted 5-year risk of cardiovascular death in the two hypertension groups. On multiple linear regression analysis, arterial SI and CECs remained as significant predictors of the calculated 5-year risk of cardiovascular death (R2=0.37; p<0.0001). There is a consistent association between CECs, arterial stiffness, and the predictive risk of cardiovascular death among a group of patients with HHT or previously treated MHT. Registration number 05/Q2709/1.