Primary aldosteronism (PA) is associated with a high risk of cardiovascular diseases, yet less than 1% of hypertensive patients are tested for PA. This study prospectively evaluated the diagnostic yield of systematic testing for PA among hypertensive patients in a dedicated heart hospital.

All inpatients admitted under a medical cardiology team at the Victorian Heart Hospital between March-May 2026 were assessed. Aldosterone-to-renin ratios (ARR) were requested for patients with documented hypertension, or consistently elevated blood pressure above 130/80 mmHg. Exclusion criteria included overseas visitors and dialysis patients. Patients were temporarily excluded if they were in intensive care. Patients were classified as “PA Likely” if they met the 2025 Endocrine Society criteria (ARR >70 pmol/mU, plasma aldosterone concentration ≥277 pmol/L, and direct renin concentration ≤8.2 mU/L) or “PA Possible” if they had ARR >20 pmol/mU while taking interfering antihypertensive medications, or ARR >70 pmol/mU without meeting aldosterone or renin thresholds. (1)

Over three months, 811 patients were admitted, including 511 (63%) with hypertension. Of 484 eligible patients, 382 underwent screening (median age 71 years, 34% female), with 25 (6.5%) classified as PA Likely, and 91 (23.8%) as PA Possible. Ordinal logistic regression demonstrated that female sex was independently associated with increased odds of an abnormal ARR (OR 2.47, 95% CI 1.47-4.17). Higher systolic and diastolic blood pressure were also associated with abnormal ARR (OR 1.02 [1.01-1.03] and OR 1.04 [1.02-1.06] per mmHg increase, respectively).

Systematic screening of hypertensive inpatients revealed a high prevalence of abnormal ARR results, with 6.5% of patients meeting contemporary criteria for likely PA. These figures demonstrate the value of routine screening in a tertiary setting, even in the presence of acute hospitalisation and interfering medications.