Background: Primary aldosteronism (PA) is the most common cause of secondary hypertension, associated with increased cardiovascular morbidity and mortality. This study evaluated biochemical and clinical responses to mineralocorticoid receptor antagonist (MRA) therapy and identified predictors of treatment success based on the Primary Aldosteronism Medical Outcomes (PAMO) consensus. Methods: This observational study analyzed data from the TAIPAI database linked to the National Health Insurance Research Databases, including 1,305 PA patients between June 2007 and June 2021. After excluding those who underwent surgery during the study period or had relevant disease, 269 patients were classified according to their clinical and biochemical responses to MRA therapy based on the PAMO criteria. Results: Among the 269 patients (mean age: 54.9±11.5 years, 40.9% male), 22.3% achieved clinical success, 55.4% partial success, and 22.3% failed. Biochemically, 56.9% of patients achieved success, 37.5% partial success, and 5.6% failed. Notably, 14.1% of patients achieved both clinical and biochemical success. After a mean follow-up period of six years, clinical success was significantly associated with a reduction in major adverse cardiovascular events (p=0.020), whereas biochemical success alone did not show the same association. Cox proportional hazards analysis demonstrated a significant association between Charlson comorbidity score (HR=1.28, p=0.003), clinical success (HR=0.29, p=0.047), and cardiovascular outcomes. Conclusions: MRA therapy achieved clinical success in 22.3% and biochemical success in 56.9% of PA patients. After a mean 6 years follow-up, clinical success independently reduced MACE risk, regardless of whether biochemical success is achieved. This highlights the importance of prioritizing clinical outcomes in PA treatment.

The authors have declared no competing interest.

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This study complied with the Declaration of Helsinki and received approval from the Institutional Review Board of National Taiwan University Hospital, Taipei, Taiwan (No. 200611031R). All experimental protocols research was approved by the Institute Research Ethical Committee of National Taiwan University Hospital (NTUH) (Http://doi.org/10.6084/m9.figshare.21730985).

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The datasets generated and analyzed during the present study are available from the corresponding authors on request.