Subclinical atherosclerosis and fetuin-A plasma levels in essential hypertensive patients.

Abstract

The intima-media thickness (IMT) is considered as a surrogate marker for atherosclerotic disease. The aim of this study was to analyze the relationship of carotid IMT with fetuin-A in patients with essential hypertension (EH) and normal renal function. The plasma levels of fetuin-A, interleukin 6 (IL-6), tumor necrosis factor-α (TNF-α) and the biomarker of oxidative stress 8-iso-PGF2alpha were assayed in samples from 105 untreated EH patients. Carotid IMT measurements were also performed. EH was studied overall and after dividing in EH with IMT ≥ and <0.9 mm. All of the biomarkers were significantly different between the two subgroups, in particular, the fetuin-A level was lower in the patients with an IMT ≥0.9 mm. In the overall group, the linear analysis of correlation demonstrated that the IMT was significantly inversely correlated with the fetuin-A level (r=-0.40, P<0.0001) and directly with TNF-α (r=0.39, P<0.0001), IL-6 (r=0.38, P<0.0001) and 8-iso-PGF2alpha (r=0.356, P<0.0003). The multiple regression analysis performed that assigned IMT as a dependent variable showed that fetuin-A (β=-0.268, P<0.0001) was independently correlated with the IMT. Receiver-operator curves demonstrated that fetuin-A levels have a predictive power of IMT>0.9 mm (AUC (area under the curve) 0.738, P<0.0001). Our results suggest that in EH, fetuin-A is associated with the IMT independently of oxidative stress and renal function, thus predicting increases in the IMT.