Effects of Aldosterone on Human Atherosclerosis: Plasma Aldosterone and Progression of Carotid Plaque

Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada.
The Canadian journal of cardiology (Impact Factor: 3.94). 06/2012; 28(6). DOI: 10.1016/j.cjca.2012.04.014
Source: PubMed

ABSTRACT BACKGROUND: In animal models, aldosterone has adverse cardiac and vascular effects independent of blood pressure, and these are ameliorated by spironolactone or eplerenone (mineralocorticoid receptor antagonists). Both agents reduce mortality in human systolic heart failure. We studied the effect of plasma aldosterone on human carotid atherosclerosis. METHODS: The effect of plasma aldosterone on progression of carotid total plaque area (TPA) was studied using multiple linear regression, with variables that have previously been shown to maximally explain TPA variation (age, sex, total cholesterol, systolic blood pressure, diabetes, smoking, and medication for cholesterol and systolic blood pressure). RESULTS: Complete data were available in 848 patients with progression of plaque from baseline to the following year and in 571 for progression in the second year. In stepwise linear regression, plasma aldosterone was the only independent predictor of plaque progression in the first year (P = 0.005) and in the second year (P = 0.001). CONCLUSIONS: Plasma aldosterone is associated with progression of atherosclerosis. We are now planning to test the effects of mineralocorticoid receptor antagonism on plaque progression.

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