title: Use of N-terminal prohormone brain natriuretic peptide assay for etiologic diagnosis of acute dyspnea in elderly patients.
abstract: BACKGROUND
  B-type peptide assay (brain natriuretic peptide [BNP] and N-terminal prohormone brain natriuretic peptide [NT-proBNP]) is useful for the diagnosis of heart failure (HF), but few data are available on the use of these markers in elderly subjects. The aim of this study was to evaluate NT-proBNP assay for the diagnosis of acute left HF in patients older than 70 years hospitalized for acute dyspnea.
  
  
  METHODS
  We prospectively enrolled 256 elderly patients with acute dyspnea. They were categorized by 2 cardiologists unaware of NT-proBNP values into a cardiac dyspnea subgroup (left HF) and a noncardiac dyspnea subgroup (all other causes).
  
  
  RESULTS
  Mean age was 81 +/- 7 years, and 52% of the patients were women. The diagnoses made in the emergency setting were incorrect or uncertain in 45% of cases. The median NT-proBNP value was higher (P < .0001) in patients with cardiac dyspnea (n = 142; 7906 pg/mL) than in patients with noncardiac dyspnea (n = 112; 1066 pg/mL). The area under the receiver operating characteristic curve was 0.86 (95% CI 0.81-0.91). At a cutoff of 2000 pg/mL, NT-proBNP had a sensitivity of 86%, a specificity of 71%, and an overall accuracy of 80% for cardiac dyspnea. The use of 2 cutoffs (< 1200 and > 4500 pg/mL) resulted in an 8% error rate and a gray area englobing 32% of values.
  
  
  CONCLUSIONS
  NT-proBNP appears to be a sensitive and specific means of distinguishing pulmonary from cardiac causes of dyspnea in elderly patients. An optimal diagnostic strategy requires the use of 2 cutoffs and further investigations of patients with values in the gray area.
authors.affiliation: Service de Cardiologie, Béziers Hospital, Béziers, France. philippe.berdague@ch-beziers.fr
authors.forename: Philippe
authors.initials: P
authors.lastname: Berdagué
authors.forename: Pierre-Yves
authors.initials: PY
authors.lastname: Caffin
authors.forename: Isabelle
authors.initials: I
authors.lastname: Barazer
authors.forename: Christine
authors.initials: C
authors.lastname: Vergnes
authors.forename: Shahin
authors.initials: S
authors.lastname: Sedighian
authors.forename: Sébastien
authors.initials: S
authors.lastname: Letrillard
authors.forename: Romain
authors.initials: R
authors.lastname: Pilossof
authors.forename: Frédéric
authors.initials: F
authors.lastname: Goutorbe
authors.forename: Christophe
authors.initials: C
authors.lastname: Piot
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Reny
mesh_terms: D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D004417:Dyspnea / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006333:Heart Failure / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D016277:Ventricular Function, Left
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain