Figure 3.

Receiver operating characteristic (ROC) curves showing the optimal cut-offs for direct renin concentration at 2 hours (A and B) and at 3 hours (C and D) of oral furosemide test for PA diagnosis. Area under the curves (AUC) are provided and optimized cut-offs were assessed according to Youden indexes with associated diagnostic sensitivities and specificities. Since low-renin hypertension is considered a spectrum of PA, we re-analyzed the data excluding these patients from the control group (B and D). PA, primary aldosteronism.