title: Prevalence and Clinical Manifestations of Primary Aldosteronism Encountered in Primary Care Practice.
abstract: BACKGROUND
  Despite being widely recognized as the most common form of secondary hypertension, among the general hypertensive population the true prevalence of primary aldosteronism (PA) and its main subtypes, aldosterone-producing adenoma (APA) and bilateral adrenal hyperplasia (BAH), remains a matter of debate.
  
  
  OBJECTIVE
  This study sought to determine the prevalence and clinical phenotype of PA in a large cohort of unselected patients with hypertension, consecutively referred to our hypertension unit, by 19 general practitioners from Torino, Italy.
  
  
  METHODS
  Following withdrawal from all interfering medications, patients were screened for PA using the ratio of serum aldosterone to plasma renin activity. PA was diagnosed according to Endocrine Society guidelines. The diagnosis was confirmed or excluded by an intravenous saline infusion test or captopril challenge test and subtype differentiation was performed by adrenal computed tomography scanning and adrenal vein sampling, using strict criteria to define successful cannulation and lateralization of aldosterone production.
  
  
  RESULTS
  A total of 1,672 primary care patients with hypertension (569 newly diagnosed and 1,103 patients already diagnosed with arterial hypertension) were included in the study. A total of 99 patients (5.9%) were diagnosed with PA and conclusive subtype differentiation by adrenal vein sampling was made in 91 patients (27 patients with an APA and 64 patients with BAH). The overall prevalence of PA increased with the severity of hypertension, from 3.9% in stage 1 hypertension to 11.8% in stage 3 hypertension. Patients with PA more frequently displayed target organ damage and cardiovascular events compared with those without PA, independent of confounding variables.
  
  
  CONCLUSIONS
  Our results demonstrated that PA is a frequent cause of secondary hypertension, even in the general population of patients with hypertension, and indicates that most of these patients should be screened for PA.
authors.affiliation: Division of Internal Medicine and Hypertension Unit, Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Monticone
authors.affiliation: Division of Internal Medicine and Hypertension Unit, Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: Jacopo
authors.initials: J
authors.lastname: Burrello
authors.affiliation: Division of Internal Medicine and Hypertension Unit, Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Tizzani
authors.affiliation: Division of Internal Medicine and Hypertension Unit, Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Bertello
authors.affiliation: Division of Internal Medicine and Hypertension Unit, Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Viola
authors.affiliation: Division of Internal Medicine and Hypertension Unit, Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Buffolo
authors.affiliation: Azienda Sanitaria Locale, Primary Care Trust, Torino, Italy.
authors.forename: Luisa
authors.initials: L
authors.lastname: Gabetti
authors.affiliation: Clinical Chemistry Laboratory, University of Torino, Torino, Italy.
authors.forename: Giulio
authors.initials: G
authors.lastname: Mengozzi
authors.affiliation: Division of Internal Medicine and Hypertension Unit, Department of Medical Sciences, University of Torino, Torino, Italy; Medizinische Klinik und Poliklinik IV, Klinikum der Universität München, Ludwig-Maximilians-Universität München, Munich, Germany.
authors.forename: Tracy A
authors.initials: TA
authors.lastname: Williams
authors.affiliation: Division of Internal Medicine and Hypertension Unit, Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: Franco
authors.initials: F
authors.lastname: Rabbia
authors.affiliation: Division of Internal Medicine and Hypertension Unit, Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: Franco
authors.initials: F
authors.lastname: Veglio
authors.affiliation: Division of Internal Medicine and Hypertension Unit, Department of Medical Sciences, University of Torino, Torino, Italy. Electronic address: paolo.mulatero@libero.it.
authors.forename: Paolo
authors.initials: P
authors.lastname: Mulatero
mesh_terms: D000312:Adrenal Hyperplasia, Congenital / Q000150:complications; D018246:Adrenocortical Adenoma / Q000150:complications; D000328:Adult; D005260:Female; D006801:Humans; D006929:Hyperaldosteronism / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D015995:Prevalence; D011320:Primary Health Care / Q000706:statistics & numerical data*
keywords: adrenal vein sampling; aldosterone-producing adenoma; bilateral adrenal hyperplasia; hypertension; renin