Endocrine Abstracts

Introduction: Patients with adrenal adenomas appear to exhibit an appreciable prevalence of autonomous aldosterone secretion (AAS). Our aim was to evaluate the anti-hypertensive effect of targeted therapy with mineralocorticoid receptor (MR) antagonists in AAS patients.

Patients and methods: We studied 60 hypertensive patients, 21 males and 39 females, harboring an adrenal adenoma with AAS. All patients were receiving combination of anti-hypertensive treatment with inadequate blood pressure (BP) control. Subjects of Conn’s syndrome were excluded. The diagnosis of AAS was established using a modified saline infusion test (MSI), i.e. saline infusion after dexamethasone administration. Cut-off levels were developed using 72 normotensive controls with normal adrenal imaging (post MSI aldosterone levels 67 pmol/l). Following hormonal evaluation, patients were switched to receive aldosterone antagonist treatment (spironolactone or eplerenone) and followed up for eight weeks. Self-reported systolic and diastolic BP values were recorded before and after treatment modification.

Results: The mean (S.D.) age of our study population was 54.80 (10.35) years and the body mass index 30.35 (4.33) kg/m². The serum potassium concentration was 3.8 (0.4) mEq/l and the post MSI aldosterone levels 226.7 (214.1) pmol/l. The use of MSI led to the identification of 30/60 AAS patients that would be undiagnosed using the Endocrine Society guidelines. Treatment with MR antagonists resulted in a marked decrease of maximum BP values (systolic BP: 161.4 (23.6) after vs 126.3 (10.2) mmHg before and diastolic BP: 97.9 (12.5) after vs 79.7 (7.4) mmHg before respectively, P<0.001 in both cases; Fig. 1).

Conclusions: We showed a remarkable anti-hypertensive effect of MR antagonists in adrenal adenoma patients with AAS. These patients would have been unrecognized without the use of the recently proposed cut-offs for AAS diagnosis. Our findings await validation with further cohorts. Targeted therapy is expected not only to adequately control BP, but also reduce the adverse aldosterone-mediated cardiovascular actions.

Figure 1 Minimum (MIN) and maximum (MAX) SBP and DBP values before (B) and on mineralocorticoid receptor antagonist treatment (A) in 60 patients with AAS, P<0.001 in all cases. SBP: systolic blood pressure, DBP: diastolic blood pressure.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.