ABSTRACT
Objective:The aim of the present study was to re-evaluate the diagnostic value and optimal cutoff point of captopril challenge test (CCT) in diagnosis of primary aldosteronism (PA).Methods:This is a retrospective study. All patients with a high risk for PA underwent screening test, and then proceeded to CCT and fludrocortisone suppression test (FST) on different days. The FST was used as a reference standard for PA. The plasma renin concentration (PRC) and plasma aldosterone concentration (PAC) were measured with an automated chemiluminescence immunoassay. Random number method was performed in the patients with unilateral primary aldosteronism (UPA), in order to make the proportion of the analyzed UPA in PA was 35%. Receiver operating characteristic (ROC) analyses were performed to compare diagnostic accuracy.Results:A total of 543 patients with 400 PA patients and 143 essential hypertension (EH) patients were enrolled. The diagnostic value of post-CCT PAC was significantly higher than that of the post-CCT plasma aldosterone-renin ratio (ARR), and that of the PAC suppression percentage, respectively. The area under the ROC curve (AUC ROC) was 0.86 (0.83, 0.89) for PAC, 0.78 (0.74, 0.82) for ARR, and 0.62 (0.56, 0.67) for the PAC suppression percentage (all P<0.01), respectively. The optimal cutoff point of post-CCT PAC for PA was 110 ng/L, in which the sensitivity and specificity were 73.25% and 79.02%, respectively. The diagnostic efficiency of post-CCT PAC was not improved either in combination with PAC suppression percentage or in combination with post-CCT ARR. Conclusions:CCT is a useful test for the confirmation of PA. PAC level of 110 ng/L at 2 h after 50 mg of captopril is recommended as an optimal cutoff point for the diagnosis of PA.
ABSTRACT
Primary aldosteronism is an important cause of secondary hypertension with the prevalence of 10%-20%in hypertensive patients. Compared with essential hypertension, primary aldosteronism patients have more cardiovascular and cerebrovascular complications. In this article, we will make a discussion on the development and current situation of primary aldosteronism by means of its prevalence, case detection, case confirmation, subtype classification, treatment and basic research.
ABSTRACT
Objective To evaluate the value of captopril challenge test (CCT) in the diagnosis of primary aldosteronism (PA).Methods A total of 674 patients [(45.0±13.7) years, men 341, women 333] admitted to Peking Union Medical College Hospital from 2000 to 2015 were analyzed.Among them, 222 subjects were with essential hypertension (EH), 28 were with pheochromocytoma (PHEO), 246 were with idiopathic hyperaldosteronism (IHA) and 178 were with aldosterone producing adenoma (APA).All patients received CCT.24 h urine sodium was measured in partial patients.Plasma renin activity (PRA), aldosterone (ALD) were detected.Results Compared with EH [PRA: before 0.5(0.2,0.9) μg·L-1·h-1, after 0.8(0.4,1.5) μg·L-1·h-1;ALD: before (393±122) pmol/L, after (360±97) pmol/L] and PHEO [PRA: before 0.3(0.1,0.9) μg·L-1·h-1, after 0.4(0.1,1.6) μg·L-1·h-1;ALD: before (396±108) pmol/L, after (374±114) pmol/L], lower levels of PRA and higher levels of ALD before and after CCT were observed in PA patients [PRA: before 0.1 (0.1,0.2) μg·L-1·h-1, after 0.1 (0.1,0.2) μg·L-1·h-1;ALD: before (468±216) pmol/L;after (457±199) pmol/L].After CCT, the suppression rate of ALD [2.8% (-8.8%,15.4%) vs 6.6% (-4.3%, 17.6%)] and increasing rate of PRA [0(0,50%) vs 50%(0, 200%)] in PA patients were lower than those in EH patients.The ALD/PRA ratio (ARR) were higher in PA than that in EH or PHEO patients.In the EH subjects, ALD levels of seated posture were higher than those of recumbent posture both before and after receiving captopril, but with no changes in ARR after CCT.No significant differences in ALD and ARR (before and after receiving captopril) were observed between seated and recumbent position in the PA group.The ARR after CCT tended to decrease in EH subjects with elevated urine-sodium compared with those with normal urine-sodium.No changes could be viewed in ALD and PRA levels between normal urine-sodium and elevated urine-sodium groups among APA, IHA and EH patients either before or after CCT.Among patients with APA, the ALD levels before CCT and the ARR after CCT were lower in the patients with AngiotensionⅡ(AngⅡ) reactive than those without.A ROC curve analysis suggested that the optimal cutoff value was 46.2 (ALD unit:ng/dl;PRA unit:μg·L-1·h-1) for ARR after challenge in diagnosing PA, with the sensitivity of 88.7% and specificity of 84.8%.Conclusions ARR after 25 mg captopril had high sensitivity and specificity in diagnosis of PA with the cutoff of 46.2.Seated CCT could replace recumbent CCT as a more confirmatory test.The PRA increasing rate should be taken into consideration when diagnosis of PA.
ABSTRACT
BACKGROUND: Diagnosis of primary aldosteronism (PA) begins with aldosterone-to-renin ratio (ARR) measurement followed by confirmative tests. However, the ARR has high false positive rates which led to unnecessary confirmatory tests. Captopril challenge test (CCT) has been used as one of confirmatory tests, but the accuracy of it in the diagnosis of PA is still controversial. We aimed to examine the clinical efficacy of CCT as a post-screening test in PA. METHODS: In a prospective study, we enrolled subjects with suspected PA who had hypertension and ARR >20 (ng/dL)/(ng/mL/hr). Sixty-four patients who underwent both the saline infusion test and the CCT were included. RESULTS: The diagnostic performance of plasma aldosterone concentration (PAC) post-CCT was greater than that of ARR post-CCT and ARR pre-CCT in PA (area under the curve=0.956, 0.797, and 0.748, respectively; P=0.001). A cut-off value of 13 ng/dL showed the highest diagnostic odds ratio considering PAC post-CCT at 60 and 90 minutes. A PAC post-CCT of 19 ng/dL had a specificity of 100%, which can be used as a cut-off value for the confirmative test. Determining the diagnostic performance of PAC post-CCT at 90 minutes was sufficient for PA diagnosis. Subjects with PAC post-CCT at 90 minutes <13 ng/dL are less likely to have PA, and those with PAC post-CCT at 90 minutes ≥13 but <19 ng/dL should undergo secondary confirmatory tests. CONCLUSION: The CCT test may be a reliable post-screening test to avoid the hospitalization in the setting of falsely elevated ARR screening tests.
Subject(s)
Humans , Aldosterone , Captopril , Diagnosis , Hospitalization , Hyperaldosteronism , Hypertension , Mass Screening , Odds Ratio , Plasma , Prospective Studies , Sensitivity and Specificity , Treatment OutcomeABSTRACT
Primary hyperaldosteronism(PA),with a high prevalence of 10%~20% in normal population,is an important cause of secondary hypertension.Compared with essential hypertension patients,PA patients have higher risks for cardiovascular and cerebrovascular complications.Early diagnosis of primary hyperaldosteronism is of great importance.This article is to discuss the prevalence,diagnosis,case confirmation,subtype classification and treatment of primary hyperaldosteronism.