Increased intima-media thickness of the common carotid artery in primary aldosteronism in comparison with essential hypertension

Background Aldosterone contributes to the accumulation of collagen fibers and extracellular matrix in arterial wall. The aim of this study was to compare intima-media thickness (IMT) of the common carotid artery and carotid bifurcation in patients with primary aldosteronism, essential hypertension and healthy controls. Methods Carotid ultrasound studies were carried out in 33 patients aged 42 - 72 years with primary aldosteronism, 52 patients with essential hypertension and in 33 normotensive controls. Results The patients with primary aldosteronism had significantly higher IMT of the common carotid artery than patients with essential hypertension and controls (0.987 +/- 0.152 mm; 0.892 +/- 0.154 mm versus 0.812 +/- 0.124 mm; P < 0.001; P < 0.05). There was also significantly higher IMT of the common carotid in patients with essential hypertension compared to control group ( 0.892 +/- 0.154 mm versus 0.812 +/- 0.124 mm; P < 0.01). The differences between both hypertensive groups remained statistically significant after adjustment for age and 24-h systolic blood pressure (P=0.001). The differences of the IMT in the carotid bifurcation were statistically significant only between patients with primary aldosteronism and controls (1.157 +/- 0.243 mm versus 0.994 +/- 0.199 mm; P < 0.05). Conclusion Patients with primary aldosteronism have increased common carotid IMT compared to the patients with essential hypertension. This finding could be caused by the deleterious effects of aldosterone excess on the fibrosis and thickening of the arterial wall, mainly in the straight segments of vessels.