Prevalence of Primary Aldosteronism Among Hypertensive Patients in the Bulgarian Reference Centre for Endocrinology

Author: Joanna Matrozova, Sabina Zacharieva, Georgi Kirilov, Mihail Boyanov, Vladimir Hristov

Abstract: 

Objective. Primary aldosteronism (PA) has long been considered a rare cause of hypertension, but a higher prevalence was suggested in the last 15 years. Until now there are no data on the prevalence of PA in Bulgaria. The aim of this study was to evaluate the prevalence of PA in a group of consecutive hypertensive patients, including patients with adrenal incidentalomas, referred to the Clinical Centre of Endocrinology in Sofia, Bulgaria.

 

Methods. The aldosteronе to renin ratio (ARR)>750 (pmol/l)/(ng/ml/h) was used as a positive screening test. In patients with an elevated ARR together with aldosterone > 416 pmol/l the Captopril test was performed to confirm the diagnosis of PA. Adrenal CT scan was used to differentiate between the two main subtypes of PA- aldosterone-producing adenoma (APA) and idiopathic hyperaldosteronism (IHA) and the diagnosis of APA was retrospectively confirmed after surgery.

 

Results. After excluding other forms of endocrine hypertension, except PA, we investigated a total of 472 consecutive hypertensive patients, among them 96 patients with adrenal incidentalomas. Final diagnosis of PA was reached in 38 patients (8,05%) in the entire hypertensive population and in 12 patients (12,5%) among hypertensive patients with adrenal incidentalomas. In the group of PA 15 patients (39,5%) were diagnosed with APA and 23 patients (60,5%) had an IHA. Among all patients with PA 21 (55,3%) presented with hypokalemia.

 

Conclusion. Our findings of a relatively high prevalence of PA support an early screening and diagnosis of this potentially curable disease and especially in hypertensive patients with adrenal incidentalomas.