Expert Consensus on the Primary Aldosteronism Severity Classification (EC-PASC) and its Strategic Application in Indicating Adrenal Venous Sampling

Abstract Objective Severity classifications are essential for many diseases to prioritize patient management tasks such as diagnosis, treatment, and follow-up. Primary aldosteronism (PA), a common cause of secondary hypertension, lacks a standardized severity scale despite generally requiring invasive diagnostics like adrenal venous sampling (AVS). This study aimed to develop a global expert consensus-based classification for PA severity to improve clinical decision-making. Methods A panel of 45 international experts from 40 centers across four continents used the Delphi method to create a consensus severity classification for PA. This classification was then applied retrospectively to 2,593 PA patients from 26 centers to assess its association with the disease subtype. Results After four rounds, the Primary Aldosteronism Severity Classification (PASC), which integrates biochemical and clinical parameters including serum potassium, blood pressure, and basal plasma aldosterone concentration, was established. PASC classifies PA into mild (3 and 4 points), moderate (5 - 7 points), and severe (8 and 9 points). Among the cohort from 26 centers, 13.9%, 63.0%, and 23.1% were classified as mild, moderate, and severe, respectively, aligning with lateralized subtype prevalence rates of 14.7%, 44.6%, and 72.6%. Conclusion PASC is a newly developed simplified, semi-quantitative classification of PA severity. The correlation between PASC and lateralized PA subtype supports its potential to provide graded recommendations of AVS prior to surgical indication in each patient.