Endocrine society 2025 diagnostic criteria increase primary aldosteronism detection in hypertensive patients: a comparative study with 2016 guidelines

Background: Primary aldosteronism (PA) is the most common cause of secondary hypertension, associated with disproportionate cardiovascular morbidity. The 2025 Endocrine Society (ES) guidelines revised diagnostic criteria, allowing diagnosis based on a biochemical triad (suppressed renin, elevated aldosterone and aldosterone-to-renin ratio, ARR) without mandatory confirmatory testing. We compared PA detection and diagnostic performance using ES 2016 versus ES 2025 algorithms in hypertensive patients referred to a specialized center. Methods: We retrospectively analyzed 137 consecutive patients referred for secondary hypertension work-up to Strasbourg University Hospital (June 2024 - June 2025). All underwent standardized hormonal evaluation and saline infusion testing (SIT). PA was defined according to ES 2016 (ARR >23 ng/mUI with aldosterone ≥200 ng/L, or 90-200 ng/L with positive saline test) and ES 2025 criteria with locally adapted thresholds (ARR >18.7 ng/ng, renin ≤6.15 ng/L, aldosterone ≥75 ng/L). Results: PA prevalence increased from 8.8% (n = 12) with ES 2016 to 16.1% (n = 22) with ES 2025 criteria (p = 0.009). Diagnostic concordance was high (91.7%, κ = 0.61). Net reclassification improvement ranged from +148% to +175%. Newly identified patients exhibited milder PA phenotypes with less severe/resistant hypertension (27% vs 73%, p = 0.03), lower aldosterone levels (95 vs 185 ng/L, p < 0.001), and predominantly negative SIT (82%). Despite a 50% false-negative rate, positive SIT remained the only independent predictor of PA diagnosis (OR = 3.25, 95%CI 1.22-8.67, p = 0.019). Conclusion: ES 2025 criteria increase PA detection by identifying milder forms not captured by previous algorithms. These findings support a phenotype-based diagnostic approach and question the systematic use of confirmatory testing.