Predictors of treatment response to mineralocorticoid receptor antagonists in primary aldosteronism: insights from the SPAIN-ALDO registry.

BACKGROUND

Data on factors predicting favorable response to medical therapy in primary aldosteronism, based on Primary Aldosteronism Medical treatment Outcome (PAMO) criteria, remain limited.

AIM: This study aimed to identify baseline parameters independently associated with clinical and biochemical responses to mineralocorticoid receptor antagonist (MRA) therapy after at least 6  months of treatment.

METHODS

Primary aldosteronism patients from the SPAIN-ALDO registry, treated medically with MRA (or amiloride) and with available clinical and/or biochemical follow-up data after at least 6 months of therapy were included.

RESULTS

A total of 402 patients (38.3% women; mean age 57 ± 11.8 years) were analyzed. Median follow-up duration was 38  months [interquartile range (IQR) 20-76]. At last visit, 55% of patients were receiving spironolactone, 44% eplerenone, and 1.2% amiloride. Among 389 patients with clinical follow-up data, 16.2% achieved complete clinical success, 65.5% partial response, and 18.3% showed no response. Complete clinical response was more likely in women, in patients with lower BMI, fewer antihypertensive medications, and higher potassium levels. Among 261 patients with biochemical follow-up data, 50.1% had complete biochemical response, 21.5% partial, and 28.4% absent. Predictors of complete biochemical response included lower baseline aldosterone concentration, higher baseline renin levels, use of spironolactone rather than eplerenone, and higher MRA doses.

CONCLUSION

Early identification of primary aldosteronism and optimized titration of MRA therapy, especially with eplerenone, are crucial for improving clinical and biochemical outcomes.