DIAGNOSTIC ACCURACY OF 24-HOUR URINARY ALDOSTERONE TO CREATININE RATIO AND 24-HOUR URINARY ALDOSTERONE FOR PRIMARY ALDOSTERONISM IN DIFFERENT AGE GROUP

Abstract

Objective: The aim of this study was to explore and evaluate the diagnostic accuracy of 24-hour urinary aldosterone to creatinine ratio (UACR) and 24-hour urinary aldosterone and in different age group. Design and method: There were 423 patients eligible and consecutively enrolled in this study. After 1:2 propensity score matching (PSM) analysis, 100 patients were in primary aldosterone (PA) group and 194 patients were in essential hypertension (EH) group. The information of clinical characteristic and biochemistry measurement were collected and analysis. Receiver operator characteristic curve (ROC) was introduced and calculated area under the curve (AUC) to explore the diagnostic accuracy and the optimal cut-off value. Results: There was no significant difference for the average age in PA group (53.38±11.31) and in EH group (52.77±11.25) (P>0.05). The 24-hour UACR and urinary aldosterone was higher in PA group (1.1 ug/(mmol/L) vs. 0.7 ug/(mmol/L), 6.4 ug/24h vs. 4.8 ug/24h, P<0.05) among all age group. The optimal cut-off value of 24-hour UACR was 1.2 ug/(mmol/L) with 0.702 for AUC and 0.300 for the Youden index, in contrast with 11.4 ug/24h, 0.652 and 0.257 for 24-hour UACR. For those 55 years old or below, it was the same for both the two index, while the optimal cut-off value was declined to 0.8 ug/(mmol/L) for 24-hour UACR and 2.7 ug/24h for 24-hour urinary aldosterone among those over 55 years old. Conclusions: 24-hour UACR was a promising index and was better than 24-hour urinary aldosterone on PA diagnosing. More research is needed to explore the underlying influence factors.