C-reactive protein and aortic stiffness and wave reflection in middle-aged and elderly men from the community

High plasma C-reactive protein (hs-CRP) levels and arterial stiffness are risk factors for cardiovascular diseases. Pulse wave velocity (PWV) and augmentation index (AIx) have been found to be elevated in patients with vascular inflammation, diabetes mellitus, hypertension, hypercholesterolemia and in smokers. We investigated the relation of high-sensitivity CRP (hs-CRP) with aortic stiffness in 362 men. The levels of hs-CRP were measured using a nephelometric method. Aortic PWV and AIx were assessed from carotid-femoral segment and radial artery waveforms with the use of the SphygmoCor device. In the crude model, aortic PWV increased significantly with increasing serum hs-CRP levels; PWV increased by 2.48 m/s (95% CI 1.58; 3.38) in the fifth compared to the first quintile of hs-CRP. In the adjusted model, the PWV increased by 0.84 m/s (95% CI 0.13; 1.55) in the fifth quintile compared to the first quintile (P-value was 0.02). In the crude model, AIx increased significantly with increasing serum hs-CRP levels; AIx increased by 7.17% (95% CI 3.72; 10.62) in the fifth versus the first quintile. Adjusted for confounders, AIx remained 4.57% (95% CI 1.32; 7.82) higher in the fifth compared to the first quintile (P-value for trend was < 0.01). More adjustment for subclinical atherosclerosis attenuated the beta-coefficient for PWV (difference 0.71 m/s (95% CI 0.01; 1.41), but not for AIx (4.60% (95% CI 1.34; 7.85)). In summary, low-grade inflammation seems to be independently related to increase of aortic artery stiffness over and above traditional risk factors and atherosclerosis.