Screening and Diagnosis Trends for Primary Aldosteronism: A Longitudinal Nationwide Cohort Study of 7.8 Million People.

Background: Primary aldosteronism (PA) is a common, treatable cause of hypertension for which screening is widely recommended but rarely performed in clinical practice. However, real-world screening and diagnosis patterns across the entire hypertensive population remain unknown. This study aimed to delineate the 22-year state of nationwide PA screening and diagnosis rates among all hypertensive population in Taiwan. Methods: In this nationwide retrospective cohort study from 2001 to 2022, we identified all patients with hypertension using a national health insurance database. We calculated annual PA screening and diagnosis rates, with particular focus on high-risk subgroups, including patients with resistant hypertension, early-onset hypertension, hypokalemia, and other comorbidities warranting screening. Results: Among 7.8 million patients with hypertension, a total of 4.4% received PA screening during the study period. The annual PA screening rate increased from 0.26% in 2001 to 0.75% in 2022 ( Conclusions: Despite an increase in PA screening over the past two decades, absolute rates remain critically low, falling far short of guideline recommendations, especially in high-risk groups. Our findings quantify a major implementation gap between evidence and clinical practice. As international guidelines are shifting towards broader and simpler screening protocols, there is an urgent need to improve the detection of this common and actionable condition.