title: Validity of Amino Terminal pro-Brain Natiuretic Peptide in a Medically Complex Elderly Population.
abstract: BACKGROUND
  The routine use of natiuretic peptides in severely dyspneic patients has recently been called into question. We hypothesized that the diagnostic utility of Amino Terminal pro Brain Natiuretic Peptide (NT-proBNP) is diminished in a complex elderly population.
  
  
  METHODS
  We studied 502 consecutive patients in whom NT-proBNP values were obtained to evaluate severe dyspnea in the emergency department. The diagnostic utility of NT-proBNP for the diagnosis of congestive heart failure (CHF) was assessed utilizing several published guidelines, as well as the manufacturers suggested age dependent cut-off points.
  
  
  RESULTS
  The area under the receiver operator curve (AUC) for NT-proBNP was 0.70. Using age-related cut points, the diagnostic accuracy of NT-proBNP for the diagnosis of CHF was below prior reports (70% vs. 83%). Age and estimated creatinine clearance correlated directly with NT-proBNP levels, while hematocrit correlated inversely. Both age > 50 years and to a lesser extent hematocrit < 30% affected the diagnostic accuracy of NT-proBNP, while renal function had no effect. In multivariate analysis, a prior history of CHF was the best predictor of current CHF, odds ratio (OR) = 45; CI: 23-88.
  
  
  CONCLUSIONS
  The diagnostic accuracy of NT-proBNP for the evaluation of CHF appears less robust in an elderly population with a high prevalence of prior CHF. Age and hematocrit levels, may adversely affect the diagnostic accuracy off NT-proBNP.
  
  
  BACKGROUND
  Congestive Heart Failure; Natriuretic peptides; Diagnosis; Elderly Patients.
authors: Departments of Medicine (Division of Cardiovascular Medicine) and Pathology, Bridgeport Hospital, Bridgeport, CT., Yale University School of Medicine, USA.
authors: Mazhar A
authors: MA
authors: Afaq
authors: Azadeh
authors: A
authors: Shoraki
authors: Oleg
authors: O
authors: Ivanov
authors: Janardhan
authors: J
authors: Srinivasan
authors: Lawrence
authors: L
authors: Bernstein
authors: Stuart W
authors: SW
authors: Zarich