Exploration Of The Seated Saline Suppression Test For The Diagnosis Of Primary Aldosteronism In The Chinese Population.

ABSTRACT

OBJECTIVE: We prospectively investigated the accuracy of the seated saline suppression test (SSST) in 113 patients with hypertension (including 93 primary aldosteronism [PA] and 20 essential hypertension patients) in the Department of Endocrinology and Metabolism. METHODS: Each patient underwent a recumbent saline suppression test (RSST) and SSST. The accuracy of the SSST for a confirmative PA diagnosis and subtype classification was evaluated and compared with the RSST. RESULTS: The area under the receiver operating characteristic (ROC) curve of plasma aldosterone concentration (PAC) for the SSST was significantly greater than that for the RSST (0.945±0.0199 vs. 0.828 ± 0.0404; P<.05). The ROC analysis showed that the optimal PAC cut-off values were 12.94 ng/dL for the SSST (sensitivity 86.02%, specificity 95%; Youden index [YI] 0.810) and 12.04 ng/dL for the RSST (sensitivity 83.15%, specificity 57%; YI 0.401). The optimal PAC cut-off value for classifying aldosterone-producing adenoma and idiopathic hyperaldosteronism was 18.12 ng/dL for the SSST (sensitivity 73.5%, specificity 79.5%). No patients experienced adverse events during the SSST. CONCLUSION: The SSST is safe and convenient for PA diagnosis. The accuracy of the SSST for a confirmatory diagnosis of PA was better than that of the RSST. The SSST is a reliable alternative for PA confirmation in Chinese individuals. ABBREVIATIONS APA = aldosterone-producing adenoma; ARR = aldosterone to renin ratio; AVS = adrenal vein sampling; CT = computed tomography; EH = essential hypertension; IHA = idiopathic hyperaldosteronism; MRI = magnetic resonance imaging; PA = primary aldosteronism; PAC = plasma aldosterone concentration; PRA = plasma renin activity; ROC = receiver operating characteristic; RSST = recumbent saline suppression test; SSST = seated saline suppression test; YI = Youden index.