Relationship between C reactive protein and pulse pressure is not mediated by atherosclerosis or aortic stiffness

BACKGROUND: Pulse pressure (PP), C reactive protein (CRP) and soluble intercellular adhesion molecule-1 (sICAM-1) levels have been associated with cardiovascular prognosis. Interestingly, previous reports have shown that PP was associated both with CRP and sICAM-1. The mechanisms underlying these associations remain unknown. On the one hand, it has been shown that PP influences, via endothelial function, the expression of various molecules, which in turn may generate inflammation. On the other hand, inflammation-induced changes in the arterial wall, modifying the PP, may be the confounding factor of these relationships. The aim of the present study was to investigate the role played by the arterial structure and the aortic stiffness on these relationships. METHODS: In a cross-sectional population sample of 891 healthy subjects, carotid-femoral pulse wave velocity and blood pressure were measured in the supine position. The common carotid intima-media thickness and the presence of plaques were assessed by ultrasonography. CRP and sICAM-1 levels were measured by an immunonephelemetric method and an immunoenzymatic method, respectively. RESULTS: A positive relationship was found between PP and CRP (P < 0.001). This relationship remained after adjustment for classical cardiovascular risk factors, and successively for mean blood pressure, intima-media thickness, presence of plaques and pulse wave velocity (P < 0.05). No significant association was observed between PP and sICAM-1. CONCLUSIONS: The results of this study demonstrate that changes in arterial structure and in arterial stiffness are not confounding factors in the relationship between PP and CRP.