title: Effect of renal failure on N-terminal Pro-Brain natriuretic peptide in patients admitted to emergency department with acute dyspnea.
abstract: OBJECTIVE
  Preexisting renal failure diminishes the excretion of N-Terminal Pro-Brain Natriuretic Peptide (NT-proBNP), therefore limits the diagnostic value of this peptide for concomitant heart failure. The aim of this study was to evaluate the association between NT-proBNP and the stages of renal dysfunction in a typical population attended to emergency department with acute dyspnea.
  
  
  METHODS
  In this cross-sectional study, all consecutive patients with acute dyspnea underwent clinical evaluation, laboratory assessment of NT-proBNP, and echocardiographic examinations. Among subjects, 54.5% were diagnosed as heart failure. Grouping variables according to renal function capacity and ejection fraction, independent variables were compared with Kruskal-Wallis or ANOVA with posthoc tests. Correlation and linear regression analysis were done to analyze the variables associated with NT-proBNP. The diagnostic performance of NT-proBNP was evaluated by receiver-operating characteristic (ROC) curve.
  
  
  RESULTS
  Serum median NT-proBNP level in patients with severe renal impairment was significantly higher than moderate and mildly decreased renal functions (p=0.001). In patients with moderate and severe left ventricular failure, NT-proBNP was significantly higher compared with normal subjects (LVEF>50%) (p=0.040, and 0.017, respectively). Renal dysfunction was associated in 56% of patients with heart failure. The area under the ROC curve of NT-proBNP for identifying left ventricular failure in patients with renal failure (eGFR<90 mL/min/1.73 m2) was 0.649 and reached significant difference (95% CI:0.548-0.749, p=0.005).
  
  
  CONCLUSIONS
  In addition to NT-proBNP measurement in clinical judgement of heart failure, renal functions have to be taken into consideration to avoid misdiagnosis.
authors.affiliation: Department of Clinical Chemistry, Tepecik Training and Research Hospital, İzmir-Turkey. sdcuhadar@yahoo.com.
authors.forename: Ayfer
authors.initials: A
authors.lastname: Çolak
authors.forename: Serap
authors.initials: S
authors.lastname: Çuhadar
authors.forename: Burcu
authors.initials: B
authors.lastname: Gölcük
authors.forename: Yalçin
authors.initials: Y
authors.lastname: Gölcük
authors.forename: Öner
authors.initials: Ö
authors.lastname: Özdoğan
authors.forename: Işil
authors.initials: I
authors.lastname: Çoker
mesh_terms: D015415:Biomarkers / Q000097:blood*; D003430:Cross-Sectional Studies; D004417:Dyspnea / Q000209:etiology*; D004452:Echocardiography; D004636:Emergency Service, Hospital; D005260:Female; D006333:Heart Failure / Q000097:blood / Q000150:complications / Q000175:diagnosis* / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010343:Patient Admission; D010446:Peptide Fragments / Q000097:blood*; D011237:Predictive Value of Tests; D012372:ROC Curve; D051437:Renal Insufficiency / Q000097:blood / Q000150:complications*
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain