The Association of Microalbuminuria With Aortic Stiffness Is Independent of C-Reactive Protein in Essential Hypertension

Abstract

BACKGROUND: It has not been fully elucidated whether microalbuminuria (MAU) and high-sensitivity C-reactive protein (hsCRP) are associated with aortic distensibility independently of each other. Our study was aimed to evaluate the independent relationships of urinary albumin excretion rate (AER) and hsCRP with aortic stiffness in hypertensive patients. METHODS: We enrolled 140 untreated nondiabetic essential hypertensives (mean age: 48 +/- 12 years). In all subjects, 24-hour AER and plasma levels of hsCRP were determined by immunoenzymatic assay. MAU was defined as an AER of 20-200 microg/min. Aortic stiffness was assessed by measurement of carotid-femoral pulse wave velocity (PWV). RESULTS: Carotid-femoral PWV, adjusted for age and mean arterial pressure (MAP), was higher in subjects with MAU (n = 41) than in those without it (n = 99) (11.6 +/- 2.3 vs. 9.9 +/- 1.8 m/s; P < 0.001) and in subjects with hsCRP above the median value when compared to those with lower levels of hsCRP (10.8 +/- 2.1 vs. 10 +/- 2.1 m/s; P = 0.026). In multiple regression analysis, AER and hsCPR remained independent predictors of aortic stiffness (beta = 0.24; P < 0.001 and beta = 0.15; P = 0.03, respectively). CONCLUSIONS: Our results suggest that in patients with essential hypertension, MAU and CRP are independently associated with an increased aortic stiffness.