1. Seated Saline Suppression Test Is Comparable With Captopril Challenge Test for the Diagnosis of Primary Aldosteronism: A Prospective Study
- Author
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Jun Yang, Ying Song, Zhixin Xu, Qingfeng Cheng, Zhengping Feng, Wenwen He, Qifu Li, Liu Bin, Zhihong Wang, Zhipeng Du, Shumin Yang, and Jinbo Hu
- Subjects
medicine.medical_specialty ,Captopril ,genetic structures ,Endocrinology, Diabetes and Metabolism ,Fludrocortisone ,Youden's J statistic ,Urology ,030209 endocrinology & metabolism ,Essential hypertension ,Lower risk ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,Primary aldosteronism ,Hyperaldosteronism ,Renin ,medicine ,Humans ,Prospective Studies ,030212 general & internal medicine ,Prospective cohort study ,Aldosterone ,Receiver operating characteristic ,business.industry ,General Medicine ,medicine.disease ,Hypertension ,Captopril challenge test ,business ,medicine.drug - Abstract
Objective The saline suppression test (SST) and captopril challenge test (CCT) are commonly used confirmatory tests for primary aldosteronism (PA). Seated SST (SSST) has been reported to be superior to recumbent SST. Whether SSST is better than CCT remains unclear. We aimed to compare the diagnostic accuracy of SSST and CCT in a prospective study. Methods Hypertensive patients at a high risk of PA were consecutively included. Patients with an aldosterone-renin ratio of ≥1.0 ng/dL/μIU/mL were asked to complete SSST, CCT, and the fludrocortisone suppression test (FST). Using FST as a reference standard (plasma aldosterone concentration [PAC] post FST ≥ 6.0 ng/dL), area under the receiver-operating characteristic curve (AUC), sensitivity, and specificity of SSST and CCT were calculated, and multiple regression analyses were performed to identify potential factors leading to false diagnosis. Results A total of 196 patients diagnosed with PA and 73 with essential hypertension completed the study. Using PAC post SSST and PAC post CCT to confirm PA, SSST and CCT had comparable AUCs (AUCSSST 0.87 [95% CI 0.82-0.91] vs AUCCCT 0.88 [0.83-0.95], P = .646). When PAC post SSST and post CCT were set at 8.5 and 11 ng/dL, respectively, the sensitivity and specificity of SSST (0.72 [0.65, 0.78] and 0.86 [0.76, 0.93]) and CCT (0.73 [0.67, 0.80] and 0.85 [0.75, 0.92]) were not significantly different. In the multiple regression analyses, 1-SD increment of sodium intake resulted in a 40% lower risk of false diagnosis with SSST. Conclusion SSST and CCT have comparable diagnostic accuracy. Insufficient sodium intake decreases the diagnostic efficiency of SSST but not of CCT. Since CCT is simpler and cheaper, it is preferred over SSST.
- Published
- 2021