Predictive performance of aldosterone-to-renin ratio in the diagnosis of primary aldosteronism in patients with resistant hypertension

Abstract

BackgroundThe systematic use of confirmatory tests in the diagnosis of primary aldosteronism (PA) increases costs, risks and complexity to the diagnostic work-up. In light of this, some authors proposed aldosterone-to-renin (ARR) cut-offs and/or integrated flow-charts to avoid this step. Patients with resistant hypertension (RH), however, are characterized by a dysregulated renin-angiotensin-aldosterone system, even in the absence of PA. Thus, it is unclear whether these strategies might be applied with the same diagnostic reliability in the setting of RH.MethodsWe enrolled 129 consecutive patients diagnosed with RH and no other causes of secondary hypertension. All patients underwent full biochemical assessment for PA, encompassing both basal measurements and a saline infusion test.Results34/129 patients (26.4%) were diagnosed with PA. ARR alone provided a moderate-to-high accuracy in predicting the diagnosis of PA (AUC=0.908). Among normokalemic patients, the ARR value that maximized the diagnostic accuracy, as identified by the Youden index, was equal to 41.8 (ng/dL)/(ng/mL/h), and was characterized by a sensitivity and a specificity of 100% and 67%, respectively (AUC=0.882); an ARR > 179.6 (ng/dL)/(ng/mL/h) provided a 100% specificity for the diagnosis of PA, but was associated with a very low sensitivity of 20%. Among hypokalemic patients, the ARR value that maximized the diagnostic accuracy, as identified by the Youden index, was equal to 49.2 (ng/dL)/(ng/mL/h), and was characterized by a sensitivity and a specificity of 100% and 83%, respectively (AUC=0.941); an ARR > 104.0 (ng/dL)/(ng/mL/h) provided a 100% specificity for the diagnosis of PA, with a sensitivity of 64%.ConclusionsAmong normokalemic patients, there was a wide overlap in ARR values between those with PA and those with essential RH; the possibility to skip a confirmatory test should thus be considered with caution in this setting. A better discriminating ability could be seen in the presence of hypokalemia; in this case, ARR alone may be sufficient to skip confirmatory tests in a suitable percentage of patients.

Application of a Radiomics Machine Learning Model for Differentiating Aldosterone-Producing Adenoma from Non-Functioning Adrenal Adenoma

“…Among the baseline clinical variables, age, Time, SBP, DBP, potassium level, and Radscore significantly differed between the APA and NAA groups. The differences in age and potassium level were consistent with the findings reported by Chen and Bioletto et al, wherein the patients in the APA group were younger and had lower potassium concentrations [16,23]. However, in the current study, patients with normal baseline blood pressure were included because of the possibility of subclinical PA.…”

“…The aldosterone renin ratio and potassium level are independent predictors of PA [23]. In the current study, the Clinic-Radscore model was constructed based on a combination of clinical characteristics and radiomics features, the ability of radiomics to distinguish APA from NAA was confirmed, and an auxiliary diagnostic method was identified for the preliminary diagnosis and classification of AI.…”

Comparison of saline infusion test and captopril challenge test in the diagnosis of Chinese with primary aldosteronism in different age groups

“…The consensus and guidelines for the diagnosis and treatment of PA have been continually updated for decades. Although the diagnostic process came to be gradually simplified, there was a wide overlap in ARR values between normokalemic patients with PA and those with EH, which need a caution if skipping the confirmatory test according to the research (23). The confirmatory test is also the key evidence for a clear diagnosis of PA and reduces unnecessary risks, such as invasive diagnosis and/or surgical treatment for patients when it is accurate and reliable (10,11).…”

Endocrine Hypertension: The Urgent Need for Greater Global Awareness

“…Hence, ARR alone may be sufficient for diagnosis in these patients and confirmatory tests can be skipped. 37 On the other hand, among normokalaemic hypertensives, there is a considerable overlap in ARR between those with PA and essential hypertension. Hence, caution should be exercised before considering skipping confirmatory tests in this setting.…”

“…Hence, caution should be exercised before considering skipping confirmatory tests in this setting. 37 Confirmation of PA depends on the demonstration of autonomous aldosterone secretion in the presence of dynamic procedures that are designed to suppress aldosterone levels, so that false-positive diagnoses and thereby inappropriate adrenal venous sampling and surgery are avoided. The available confirmatory tests include the fludrocortisone suppression test (FST), saline infusion test (SIT), and oral sodium loading test (OSLT), all of which are meant to expand the plasma volume and suppress renin.…”