Hiperaldosteronismo primario: puntos de corte del cociente aldosterona/renina / Primary aldosteronism: Aldosterone/renin ratio cut-off points

Introducción: El hiperaldosteronismo primario (HAP) es la causa más frecuente de hipertensión endocrina, con una prevalencia del 6-12% en pacientes hipertensos. El cociente aldosterona/renina es el método de cribado de elección. Dada la variabilidad de sus puntos de corte, se sugiere contar con valores de referencia propios. Objetivos: 1) Optimizar los puntos de corte del cociente aldosterona/renina para el cribado de hiperaldosteronismo con la metodología actual; 2)evaluar la correlación y la sensibilidad diagnóstica de los cocientes aldosterona/actividad de renina plasmática (RAA) y aldosterona/concentración de renina (RAC) para el cribado de hiperaldosteronismo, y 3)determinar la prevalencia de hiperaldosteronismo en nuestra población. Materiales y métodos: Se determinaron los niveles de aldosterona (RIA competitivo en fase sólida RIAZENco Zentech), actividad de renina plasmática (RIA en fase sólida DiaSorin) y concentración de renina (quimioluminiscencia Liaison DiaSorin) en 345 sujetos (136 controles y 209 hipertensos). Se calcularon los cocientes RAA y RAC. Resultados: La prevalencia de HAP, tras confirmación diagnóstica, fue del 5,9% de los hipertensos. El valor de corte para sospecha de HAP determinado por curvas ROC fue 48,9(ng/dl)/(ng/ml/h) para RAA (sensibilidad 100% y especificidad 93,6%) y 2,3(ng/dl)/(μUI/ml) para RAC (sensibilidad 100% y especificidad 90,9%). Se observó buena correlación entre RAA y RAC (ρ=0,83; p<0,0001), con una concordancia diagnóstica presuntiva del 96,6%. Conclusiones: Hemos determinado en nuestra población nuevos valores de corte de RAA y RAC para el cribado de HAP, con buena sensibilidad y concordancia como métodos de cribado. Es importante contar con rangos de normalidad propios para evitar errores diagnósticos

Introduction: Primary aldosteronism (PA) is the most common cause of endocrine hypertension, with a prevalence rate of 6-12% in hypertensive patients. Aldosterone/renin ratio (ARR) is the screening test of choice for PA. Because of the variable cut-off points of ARR, reference values related to the populations and methods considered are recommended. Objectives: (i)To optimize the ARR cut-off points for PA screening with current methods; (ii)to assess the correlation and diagnostic sensitivity of the plasma aldosterone concentration/plasma renin activity (ARR) ratio and the aldosterone concentration/renin concentration (ARC) ratios for PA screening, and (iii)to determine the prevalence of PA in our population. Materials and methods: Plasma aldosterone concentration and plasma renin activity levels were measured using radioimmunoassays (RIAZENco Zentech and RIA DiaSorin respectively), while a chemiluminescence assay (Liaison Diasorin) was used to test renin concentration. ARR and ARC ratios were calculated in 345 subjects (136 healthy subjects and 209 hypertensive patients). Results: Prevalence of PA was 5.9% after diagnostic confirmation. ROC curve analysis suggested an ARR threshold of 48.9(ng/dL)/(ng/mL/h) (100% sensitivity, 93.6% specificity) and an ARC threshold of 2.3(ng/dL)/(μIU/mL) (100% sensitivity, 90.9% specificity). Good correlation was seen between ARR and ARC (ρ=.83, P<.0001), with a presumptive diagnostic concordance of 96.6%. Conclusions: New cut-off values of ARR and ARC for screening of PA, with high sensitivity and good diagnostic concordance, were determined in the study population. It is important to have valid normal ranges to avoid diagnostic errors

Primary aldosteronism: Aldosterone/renin ratio cut-off points. / Hiperaldosteronismo primario: puntos de corte del cociente aldosterona/renina.

INTRODUCTION: Primary aldosteronism (PA) is the most common cause of endocrine hypertension, with a prevalence rate of 6-12% in hypertensive patients. Aldosterone/renin ratio (ARR) is the screening test of choice for PA. Because of the variable cut-off points of ARR, reference values related to the populations and methods considered are recommended. OBJECTIVES: (i)To optimize the ARR cut-off points for PA screening with current methods; (ii)to assess the correlation and diagnostic sensitivity of the plasma aldosterone concentration/plasma renin activity (ARR) ratio and the aldosterone concentration/renin concentration (ARC) ratios for PA screening, and (iii)to determine the prevalence of PA in our population. MATERIALS AND METHODS: Plasma aldosterone concentration and plasma renin activity levels were measured using radioimmunoassays (RIAZENco Zentech and RIA DiaSorin respectively), while a chemiluminescence assay (Liaison Diasorin) was used to test renin concentration. ARR and ARC ratios were calculated in 345 subjects (136 healthy subjects and 209 hypertensive patients). RESULTS: Prevalence of PA was 5.9% after diagnostic confirmation. ROC curve analysis suggested an ARR threshold of 48.9(ng/dL)/(ng/mL/h) (100% sensitivity, 93.6% specificity) and an ARC threshold of 2.3(ng/dL)/(µIU/mL) (100% sensitivity, 90.9% specificity). Good correlation was seen between ARR and ARC (ρ=.83, P<.0001), with a presumptive diagnostic concordance of 96.6%. CONCLUSIONS: New cut-off values of ARR and ARC for screening of PA, with high sensitivity and good diagnostic concordance, were determined in the study population. It is important to have valid normal ranges to avoid diagnostic errors.

Screening for primary aldosteronism in an argentinian population: a multicenter prospective study

Objectives Primary aldosteronism (PA) is characterized by the autonomous overproduction of aldosterone. Its prevalence has increased since the use of the aldosterone (ALD)/plasma renin activity (PRA) ratio (ARR). The objective of this study is to determine ARR and ARC (ALD/plasma renin concentration ratio) cut-off values (COV) and their diagnostic concordance (DC%) in the screening for PA in an Argentinian population.Design multicenter prospective study.Subjects and methods We studied 353 subjects (104 controls and 249 hypertensive patients). Serum aldosterone, PRA and ARR were determined. In 220 randomly selected subjects, 160 hypertensive patients and 60 controls, plasma renin concentration (PRC) was simultaneously measured and ARC was determined.Results According to the 95th percentile of controls, we determined a COV of 36 for ARR and 2.39 for ARC, with ALD ≥ 15 ng/dL. In 31/249 hypertensive patients, ARR was ≥ 36. PA diagnosis was established in 8/31 patients (23/31 patients did not complete confirmatory tests). DC% between ARR and ARC was calculated. A significant correlation between ARR and ARC (r = 0.742; p < 0.0001) was found only with PRA > 0.3 ng/mL/h and PRC > 5 pg/mL. DC% for ARR and ARC above or below 36 and 2.39 was 79.1%, respectively.Conclusion This first Argentinian multicenter study determined a COV of 36 for ARR and 2.39 for ARC. Applying an ARR ≥ 36 in the hypertensive group, we confirmed PA in a higher percentage of patients than the previously reported one in our population. As for ARC, further studies are needed for its clinical application, since DC% is acceptable only for medium range renin values.

Screening for primary aldosteronism in an argentinian population: a multicenter prospective study.

OBJECTIVES: Primary aldosteronism (PA) is characterized by the autonomous overproduction of aldosterone. Its prevalence has increased since the use of the aldosterone (ALD)/plasma renin activity (PRA) ratio (ARR). The objective of this study is to determine ARR and ARC (ALD/plasma renin concentration ratio) cut-off values (COV) and their diagnostic concordance (DC%) in the screening for PA in an Argentinian population.Design multicenter prospective study. SUBJECTS AND METHODS: We studied 353 subjects (104 controls and 249 hypertensive patients). Serum aldosterone, PRA and ARR were determined. In 220 randomly selected subjects, 160 hypertensive patients and 60 controls, plasma renin concentration (PRC) was simultaneously measured and ARC was determined. RESULTS: According to the 95th percentile of controls, we determined a COV of 36 for ARR and 2.39 for ARC, with ALD ≥ 15 ng/dL. In 31/249 hypertensive patients, ARR was ≥ 36. PA diagnosis was established in 8/31 patients (23/31 patients did not complete confirmatory tests). DC% between ARR and ARC was calculated. A significant correlation between ARR and ARC (r = 0.742; p < 0.0001) was found only with PRA > 0.3 ng/mL/h and PRC > 5 pg/mL. DC% for ARR and ARC above or below 36 and 2.39 was 79.1%, respectively. CONCLUSION: This first Argentinian multicenter study determined a COV of 36 for ARR and 2.39 for ARC. Applying an ARR ≥ 36 in the hypertensive group, we confirmed PA in a higher percentage of patients than the previously reported one in our population. As for ARC, further studies are needed for its clinical application, since DC% is acceptable only for medium range renin values.