Approximately 29% of Korean adults have hypertension; however, the prevalence of primary aldosteronism among the hypertensive population is largely unknown. The aim of our study was to evaluate the prevalence and clinical characteristics of primary aldosteronism in a tertiary-care center in Korea. We retrospectively analyzed 1173 patients with newly diagnosed or preexisting hypertension who were referred to our tertiary-care hospital between January 2013 and December 2018. Patients were screened for primary aldosteronism with the aldosterone-renin ratio and underwent a saline infusion test for diagnostic confirmation. Adrenal computed tomography and adrenal venous sampling were performed for subtype classification for primary aldosteronism. Among the 1173 patients (mean age, 51.8 years; women, 53.2%), 360 (30.7%) had positive screening-test results, of whom 71 (6.1%) were finally diagnosed with primary aldosteronism. Conclusive subtype differentiation was made in 55 patients, of whom 15 (27%) had an aldosterone-producing adenoma, 4 (7%) had unilateral adrenal hyperplasia, and 36 (66%) had bilateral adrenal hyperplasia. Patients with primary aldosteronism had a higher ambulatory blood pressure, left ventricular mass index, and urinary albumin-to-creatinine ratio than those without. Moreover, the primary aldosteronism group had a higher prevalence of left ventricular hypertrophy and albuminuria than the non-primary aldosteronism group. Primary aldosteronism may be more common (6.1%) among Korean patients with hypertension than generally recognized. Primary aldosteronism was associated with a higher degree and prevalence of target organ damage and a higher blood pressure level. Wide application of screening tests for primary aldosteronism may be beneficial in detecting this potentially curable cause of hypertension.
