Relationship between uric acid and vascular structure and function in hypertensive patients and sex-related differences.

BACKGROUND We sought to analyze the relationship between uric acid (UA) and vascular structure and function based on the carotid intima-media thickness, the pulse-wave velocity (PWV), the central arterial pressure, and the augmentation index in hypertensive patients and to evaluate the sex-related differences. METHODS A cross-sectional study was performed with 366 hypertensive individuals aged 34-75 years (men = 61.74%). The vascular structure was assessed based on the carotid intima-media thickness, the arterial stiffness was assessed by PWV, and the vascular function was assessed using hemodynamic parameters such as the central and peripheral augmentation index and the ambulatory arterial stiffness index (AASI). RESULTS In the bivariable analysis, the PWV (r = 0.28; P < 0.01) and AASI (r = 0.25; P < 0.01) were positively correlated with UA in women. The central augmentation index (r = -0.16; P < 0.05) and peripheral augmentation index (r = -0.18; P < 0.05) were negatively correlated with UA, whereas the maximum carotid intima-media thickness (r = 0.11; P < 0.05) was positively correlated with UA in the global analysis. In the multiple linear regression analysis, a positive association between PWV and UA was observed after adjusting for classical risk factors (β = 0.27; P = 0.01) in women only. In turn, a negative association was observed between the AASI and UA after adjusting for confounders in men (β = -0.06; P = 0.04), with a positive association in women (β = 0.11; P = 0.03). CONCLUSIONS Serum UA showed a positive correlation with the mean maximum intima-media thickness and PWV, and this parameter showed a negative correlation with the central and peripheral augmentation indices, although this relationship was lost after adjusting for confounding factors. AASI showed a positive association in women and a negative association in men after adjusting for confounding factors. CLINICAL TRIALS REGISTRATION Clinical Trials.gov Identifier: NCT01325064.