Endothelial progenitor cells predict vascular damage progression in naive hypertensive patients according to sex

Low levels of endothelial progenitor cells (EPCs) are associated with cardiovascular (CV) morbidity and mortality. Early indicators of vascular damage represent independent predictors of CV prognosis. The aim of this study was to evaluate the possible association of EPCs and circulating cytokine levels with vascular damage markers in naive hypertensive patients according to sex and to evaluate the role of EPCs in vascular damage progression. We enrolled 60 subjects; circulating EPCs were determined by cytometric analysis, and serum cytokines were determined by chemiluminescence microarray technology. Endothelial function was estimated with the measurement of the reactive hyperemia index (RHI), arterial stiffness (AS) was evaluated with the measurement of carotid-femoral pulse wave velocity (PWV) and carotid intima-media thickness (IMT) was determined by a high-resolution ultrasound B-mode system. Patients were evaluated at baseline and after an average follow-up of 3.0 +/- 0.6 years. RHI was correlated with EPCs and inversely related to HOMA, TNF-alpha, IL-6, hs-CRP, and IL-1 beta. PWV was positively correlated with HOMA, TNF-alpha, IL-6, IL-1 beta, and hs-CRP, and it was inversely related to EPCs. An inverse relationship was observed between c-IMT and EPCs and e-GFR. EPCs were the major predictor of the RHI and PWV. After adjustment for vascular index basal values and the other covariates, EPCs explained 17.0%, 27.7%, and 10.6% of the variability in Delta RHI, Delta PWV, and Delta c-IMT at follow-up, respectively. Our study results support the hypothesis of an etiological link between circulating EPCs and morphofunctional vascular parameters in hypertensive subjects. Of interest, circulating EPCs, after adjusting for possible confounding factors, may indicate vascular damage progression.