The aldosterone-to-renin ratio (ARR) is the guideline-recommended screening test for primary aldosteronism. However, there is limited data in regard to the diagnostic performance of the ARR.To evaluate the sensitivity and specificity of the ARR as a screening test for primary aldosteronism.We searched MEDLINE, Embase, and Cochrane until February 2020.Observational studies assessing ARR diagnostic performance as a screening test for primary aldosteronism were selected. To limit verification bias, only studies where dynamic confirmatory testing was implemented as a reference standard regardless of the ARR result were included.Study-level data was extracted and risk of bias and applicability were assessed using the QUADAS-2 tool.Ten studies, involving a total of 4,110 participants, were included. Potential risk of bias related to patient selection was common and present in half of the included studies. The population base, ARR positivity threshold, laboratory assay, and reference standard for confirmatory testing varied substantially between studies. The reported ARR sensitivity and specificity varied widely with sensitivity ranging from 10-100% and specificity ranging from 70-100%. Notably, four of the ten studies reported an ARR sensitivity of <50% suggesting a limited ability of the ARR to adequately identify patients with primary aldosteronism.ARR performance varied widely based on patient population and diagnostic criteria, especially with respect to sensitivity. Therefore, no single ARR threshold for interpretation could be recommended. Limitations in accuracy and reliability of the ARR must be recognized in order to appropriately inform clinical decision-making.
Annie Hung, Sumaiya Ahmed, Ankur Gupta, Alexandra Davis, Gregory A Kline, Alexander A Leung, Marcel Ruzicka, Swapnil Hiremath, Gregory L Hundemer