Screening primary aldosteronism by plasma aldosterone-to-angiotensin II ratio.

OBJECTIVES

Primary aldosteronism (PA) is a common cause of secondary hypertension. The aldosterone-to-renin ratio (ARR) is the current recommended biomarker for PA screening, but it has limitations. This study evaluates another ratio, the aldosterone-to-angiotensin II ratio (AAIIR), as an alternative screening tool for PA.

METHODS

Archived plasma samples for ARR from a group of 152 hypertensive patients undergoing PA screening were retrieved for AAIIR analyses. Both AAIIR and ARR were measured by liquid chromatography-mass spectrometry methods. Correlation analysis, sensitivity, specificity, and receiver operating characteristic (ROC) curve analysis were performed to assess the diagnostic performance of AAIIR relative to ARR.

RESULTS

AAIIR showed a strong positive correlation with ARR (r=0.79, p<0.0001). The area under the ROC curve for AAIIR (0.94, 95 % CI: 0.90-0.98) was satisfactory and not significantly different from ARR (0.94, 95 % CI: 0.90-0.97, p=0.877). The optimal cutoff values were 577 (pmol/L)/(µg/L) and 60 for ARR and AAIIR, respectively. The sensitivity of AAIIR was slightly higher than ARR (91 vs. 88 %), while the specificity was comparable (85 vs. 86 %).

CONCLUSIONS

AAIIR demonstrates a comparable diagnostic performance to ARR for PA screening, with potential advantages in efficiency and reliability. Further large-scale studies are needed to validate its efficacy and establish its role in routine clinical practice.