Differences in Regulation of Cortisol Secretion Contribute to Left Ventricular Abnormalities in Patients with Essential Hypertension

Abstract

Background: Left ventricular (LV) abnormalities were reported in patients with overt and subclinical Cushing syndrome. The aim of this study was to investigate the relationships of daily plasma cortisol profile and cortisol response to an overnight suppression test with cardiac changes in patients with hypertension. Methods: In a cross-sectional study, we included 136 nondiabetic, patients with essential hypertension who were free of cardiovascular and renal complications. Plasma cortisol was measured at 8 am, 3 pm, and 12 am and at 8 am after overnight suppression with 1 mg dexamethasone (dexamethasone suppression test [DST]). Echocardiography was performed with standard B-mode and tissue-Doppler imaging. Results: LV hypertrophy was present in 30% and LV diastolic dysfunction in 51% of patients who were older and had significantly higher body mass index, systolic blood pressure, duration of hypertension, and 12 am and DST cortisol. LV mass index and relative wall thickness increased progressively across tertiles of DST cortisol, together with progressive worsening of diastolic function. LV mass index was directly related to age, systolic blood pressure, duration of hypertension, and 12 am and DST cortisol, and inversely to creatinine clearance. Multivariate regression analysis showed independent correlation of LV mass index with body mass index, systolic blood pressure, and 12 am and DST cortisol. Logistic regression showed that DST cortisol independently predicted LV hypertrophy. Conclusions: Midnight and DST plasma cortisol levels are independent determinants of LV mass and geometry in patients with essential hypertension suggesting that even minor changes in regulation of cortisol secretion could contribute to cardiac abnormalities in these patients.