Relationship between low-grade inflammation and arterial stiffness in patients with essential hypertension

Background Arterial stiffness is an independent cardiovascular risk factor in hypertensive individuals. Inflammation is associated with increased arterial stiffness and is implicated in the pathogenesis of hypertension. Objectives To examine whether low-grade inflammation contributes to arterial stiffness and wave reflections independently of blood pressure, in patients with essential hypertension and in controls. Methods We studied 235 consecutive patients with uncomplicated, never-treated essential hypertension and 103 sex- and age-matched controls. The level of inflammation was evaluated with high-sensitivity C-reactive protein (hsCRP) and serum amyloid A (SAA Arterial stiffness was assessed with carotid-femoral (c-f) and carotid-radial (c-r) pulse wave velocity (PWV), and wave reflections with augmentation index (Alx). Results In the hypertensive group, in multiple regression analysis, both PWVc-f and PWVc-r were independently correlated with log hsCRP (beta = 0.56, P = 0.006 and beta = 0.45, P = 0.016, respectively), whereas no correlation was found between PWV and log SAA (P = NS). No significant correlation was observed between heart-rate-corrected Aix and log hsCRP (P = NS) and log SAA (P = 0.07) in the same group. Similarly, in the control group, an independent association was observed between PWVc-f and PWVc-r with log hsCRP (beta = 0.68, P = 0.05 and beta = 0.74, P = 0.05 respectively), but not with log SAA (P = NS). Furthermore, no significant association was shown between heart-rate-corrected Alx and log hsCRP or log SAA (P = NS) in the control group. (P = 0.07) in the same group. Similarly, in the control group, an independent association was observed between PWVc-f and PWVc-r with log hsCRP (beta = 0.68, P = 0.05 and beta = 0.74, P = 0.05 respectively), but not with log SAA (P = NS). Furthermore, no significant association was shown between heart-rate-corrected Alx and log hsCRP or log SAA (P = NS) in the control group. Conclusions In hypertensive individuals, hsCRP is related to PWV, a direct marker of arterial stiffness, but not to Alx, a measure of wave reflections. Whether inflammation might act as a pathogenetic or modulating factor in arterial stiffening in chronic hypertension has to be confirmed.