Background and aim: Several recent studies showed conflicting results on the association between colony-forming capacity of circulating endothelial progenitor cells (EPC) and arterial hypertension, but none of it assessed arterial stiffness parameters. Therefore we aimed to investigate the relationship of EPC with blood pressure (BP) and arterial stiffness.

Methods: Sixty-four male patients (aged 49.33±5.65 years) with different stages of essential hypertension referred to the primary prevention unit for assessment of cardiovascular (CV) risk were included into the study. Detailed assessment of CV risk profile and measurements of local, regional and systemic arterial stiffness (AS) was performed. Peripheral blood samples were collected and EPC colony-forming capacity was measured in vitro using a colony-forming unit (CFU) assay.

Results: We found that EPC CFU number was inversely correlated with heart-rate adjusted aortic augmentation index (AIx@75) (R=−0.311, p=0.015). Multiple regression analysis revealed that this association remained significant after adjustment for age, mean blood pressure, smoking, blood lipids, waist circumference and fasting glucose (p<0.01). Mean blood pressure (beta=0.294, p=0.023) and number of CFU (beta=−0.315, p=0.0076) explained 19% of overall variability of AIx@75. Neither other AS parameters (aortic or radial pulse wave velocity and carotid stiffness) nor peripheral or central arterial BP were significantly associated with EPC CFU number.

Conclusion: The present study shows that in male hypertensive subjects number of EPC CFU is associated with aortic augmentation index but not the level of arterial blood pressure or other stiffness parameters.