Serum Uric Acid Elevation is Associated to Arterial Stiffness in Hypertensive Patients with Metabolic Disturbances

Chronic serum uric acid elevation (SUA) is known to be induced by dyslipidemia, hypertension, inflammation, and insulin resistance. Therefore, it has been associated with higher risk for coronary artery disease and cardiovascular mortality. Also, increased levels of SUA have been associated with regional arterial stiffness, assessed by pulse wave velocity (PWV).

To evaluate the relationships of PWV, SUA and different metabolic parameters in essential hypertensive patients.

We evaluated 445 essential hypertensive patients, by measuring office blood pressure (BP), weight, height, and waist circumference. In each patient, blood samples were drawn for biochemical evaluations and 24h urine collection. Body Mass Index (BMI) and Glomerular Filtration Rate (GFR) were calculated. Carotid-Femoral PWV and Left Ventricular Mass Index (LVMI) were measured in all patients.

All subjects (n=402), 242 males (55±0.9 yrs.; BMI: 28.9±0.3 Kg/m2) and 160 females (58±1 yrs.; BMI: 28.1±0.4 Kg/m2) had normal renal function. PWV values showed a significant association with SUA (p<0.001), Systolic BP (p<0.025) and LVMI (p<0.05). SUA showed a significant association, p<0.025: with BMI, Waist Circumference, and HDL-C; p<0.05: with Glycaemia at 120 min, Insulin at 120 min, TG, and LVMI; and p<0.001: with serum Creatinine. Backward Stepwise Regression showed that PWV could be predicted from SUA (p<0.001) and Systolic BP (p<0.05). BMI, Waist Circumference, DBP and HR did not significantly add to the ability of the equation to predict PWV.

In this population of essential hypertensive patients, SUA was associated to increased arterial stiffness and to components of the Metabolic Syndrome. These results raise the possibility that a new approach to the role of SUA, linked to cardiovascular stratification, and a most appropriate treatment might be considered.