Effect of uric acid serum levels on carotid arterial stiffness and intima-media thickness: A high resolution Echo-Tracking Study

Abstract

Serum uric acid (UA) has been shown to be a predictor of cardiovascular (CV) morbidity and mortality, and it may play a role in the pathogenesis of CV disease affecting vascular structure and function. However, there is limited evidence of its specific association with carotid artery stiffness and structure. The aim of our study was to evaluate whether UA is associated with early signs of atherosclerosis, namely local carotid arterial stiffness and intima-media thickening. We evaluated 698 consecutive asymptomatic patients, referred to the Cardiovascular Department for risk factors evaluation and treatment. All patients underwent carotid artery ultrasonography with measurement of common carotid intima-media thickness (IMT) and echo-tracking carotid artery stiffness index Beta. Patients with hyperuricemia (defined as serum uric acid ≥7 mg/dL in men and ≥6 mg/dL in women) had higher IMT (0.97±0.22 vs 0.91±0.18, p<0.001) and stiffness index Beta (8.3±3.2 vs 7.5±2.7, p=0.005). UA levels correlated with both IMT (r=0.225; p<0.001) and stiffness index Beta (r=0.154; p<0.001); the correlations were statistically significant in males and females. In a multivariate model which included age, arterial pressure, serum glucose and LDL-cholesterol, serum UA emerged as an independent explanatory variable of IMT and stiffness index Beta. Carotid IMT and local arterial stiffness are related to UA independently of established CV risk factors; UA may play a role in the early development of atherosclerosis.