SUBCLINICAL ATHEROSCLEROSIS, SERUM URIC ACID AND PLASMA ALDOSTERONE IN HYPERTENSIVE ADULTS

Abstract

Objective: aldosterone has long been classically considered to play a central role in the regulation of electrolyte and fluid volume and the maintenance of blood pressure (BP) homeostasis. Moreover, the aldosterone/mineralocorticoid system plays a key role in cardiovascular, metabolic and renal damage. This study aimed to assess the relationship between plasma aldosterone concentration (PAC) and some surrogate markers of subclinical atherosclerosis, such as carotid intima-media thickness (cIMT), ankle-brachial index (ABI) and biochemical parameters (i. e. serum uric acid – SUA, 24-h urinary albumin excretion - UAE) in subjects with essential hypertension (EH). Design and method: from January 2014 to December 2017 we consecutively enrolled 804 EH patients (407 males and 397 females, mean age 50 ± 14.5 yrs) without evident cardiovascular complications. Patients were divided in quartiles according to PAC levels. Results: Compared to the first quartile, the highest PAC quartile was associated with the highest levels of SUA (5.3 ± 1.34 vs 5.0 ± 1 mg/dl; p = 0.01) triglycerides (117.5 ± 15.7 vs 106.8 ± 10.5 mg/dl; p < 0.05), UAE (38.8 vs 17.6 mg/24ore; p < 0.05) and cIMT (0.87 ± 0.22 mm vs 0.8 ± 0.21 mm; p = 0.001). Patients of the fourth quartile also exhibited increased prevalence of carotid plaques, compared to the first quartile (26% vs. 16%; p < 0.005). Moreover, we found that in patients with PAC >160 pg/ml ABI was significantly lower compared to those with PAC < 160 pg/ml (1.01 ± 0.09 vs 1.1 ± 0.09; p < 0.022). Binary logistic regression analysis showed that PAC was an independent predictor of the presence of carotid plaques and pathological ABI (< 0.9) in the population examined. Conclusions: These findings suggest that higher values of PAC are strongly associated with higher values of SUA, triglycerides, UAE, cIMT, worse ABI and major prevalence of carotid plaques that, together with elevated BP values, are strictly correlated with higher risk of atherosclerosis and cardiovascular complications.