Study on Cutoff Revision Effects and Evaluation of NNT in Primary Aldosteronism

Inclusion Criteria: * Adults aged 18 years or older * Diagnosis of hypertension or current use of antihypertensive medications * Plasma renin activity (PRA) ≤1 ng/mL/hr * Plasma aldosterone concentration (PAC) ≥10 ng/dL by immunoassay or ≥7.5 ng/dL by liquid chromatography-tandem mass spectrometry (LC-MS/MS) * Aldosterone-to-renin ratio (ARR) \>20 by immunoassay or \>15 by LC-MS/MS * Participants meeting criteria for intermediate probability of lateralizing primary aldosteronism * For participants with ARR values between 20 and 30, repeat ARR measurement within 26 weeks demonstrating persistent ARR \>20 Exclusion Criteria: * Current use of mineralocorticoid receptor antagonists or amiloride that cannot be discontinued according to study protocol * Previous adrenalectomy * Chronic kidney disease stage 4 or higher (estimated glomerular filtration rate \<30 mL/min/1.73 m²) * Pregnancy * Current use of combined estrogen- and progesterone-containing oral contraceptive pills or hormone replacement therapy * High probability primary aldosteronism defined as hypokalemia with PRA \<0.2 ng/mL/hr and PAC \>20 ng/dL by immunoassay or \>15 ng/dL by LC-MS/MS * Low probability primary aldosteronism defined as PAC \<11 ng/dL by immunoassay or \<8 ng/dL by LC-MS/MS * Inability to undergo saline infusion test according to investigator judgment