PS-BPC02-2: CLINICAL IMPACTS OF ENDOTHELIUM-DEPENDENT FLOW-MEDIATED VASODILATION ASSESSMENT ON PRIMARY ALDOSTERONISM

Abstract

Objective: Primary aldosteronism (PA) is defined as autonomous aldosterone production from the adrenal glands and represents the most common and treatable cause of hypertension. Also, it is well known that the incidence of cardiovascular morbidity is higher among patients with PA than among those with essential hypertension (EH). Histologically, PA is divided into two major subtypes, aldosterone-producing adenoma (APA) and bilateral idiopathic hyperplasia (IHA). However, the nature of vascular function in PA patients remains to be determined. The aim of this study was to determine the vascular function and investigate the implications of vascular function assessments in the patients with PA. Design and Method: All patients were diagnosed with PA according to the guidelines of the Japan Endocrine Society. Flow-mediated dilation (FMD), as an index of endothelial function, and cardio-ankle vascular index (CAVI), as an index of arterial stiffness, were retrospectively compared between 42 patients with APA, 37 patients with IHA, and 42 patients with EH. These values were also compared with background factors, KCNJ5 mutation and clinical outcome in terms of blood pressure reduction after adrenalectomy in the APA group. Results: No differences were found among the three groups (APA, IHA and EH) with regard to age, sex, duration of hypertension, body mass index, blood pressure, renal function and hemoglobin A1c. FMD was significantly lower in the APA group (4.8 ± 2.1%) and IHA group (4.1 ± 1.9%) than in the EH group (5.7 ± 2.1%). CAVI did not differ significantly among APA, IHA and EH groups (7.9 ± 1.3, 7.8 ± 1.0, 7.8 ± 1.1, respectively). Although no significant correlations were seen between FMD and background factors (i.e. age, body mass index, renal function, glucose and lipid metabolic parameters, and hormonal data) in the IHA group, FMD correlated negatively with BMI and plasma aldosterone concentration in the APA group (rs = -0.313, rs = -0.342, respectively). No significant difference in FMD (4.8 ± 1.4%, 4.5 ± 2.1%, respectively) or CAVI (8.1 ± 1.8, 8.0 ± 1.1, respectively) was seen between the KCNJ5-mutant group and the wild-type group. A cut-off FMD of 4.3% was selected for complete clinical success after adrenalectomy, offering 78% sensitivity and 80% specificity. Conclusions: Patients with PA displayed impaired endothelial function. Complete clinical success after adrenalectomy was associated with preserved endothelial function. This study provides a better understanding of FMD assessment in patients with PA.