Circulating endothelial cells, arterial stiffness, and cardiovascular risk stratification in hypertension

Background: Given the growing burden of cardiovascular disease, there is increasing interest in strategies to help predict future cardiovascular risk. Aims: To investigate the relationship between endothelial damage/dysfunction, arterial stiffness, and their association with predicted risk of future cardiovascular death among patients with hypertension. Methods: 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). Results: 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 (R-2 = 0.37; p < 0.0001). Conclusion: 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.