title: β-trace protein and cystatin C as predictors of long-term outcomes in patients with acute heart failure.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the prognostic importance of novel markers of renal dysfunction among patients with acutely destabilized heart failure (ADHF).
  
  
  BACKGROUND
  β-trace protein (BTP) and cystatin C are newer biomarkers for renal dysfunction; the prognostic importance of these tests, particularly BTP, relative to standard measures of renal function remains unclear.
  
  
  METHODS
  A total of 220 consecutive hospitalized patients with ADHF were prospectively studied. Blood samples were collected on presentation. In-hospital worsening renal function, as well as mortality and/or heart failure (HF) hospitalization, over a median follow-up period of 500 days was examined as a function of BTP or cystatin C concentrations; results were compared with creatinine, estimated glomerular filtration rate, and blood urea nitrogen.
  
  
  RESULTS
  Neither BTP nor cystatin C was associated with worsening renal function during the index hospitalization. A total of 116 patients (53%) either died or were hospitalized for HF during follow-up. Those with adverse outcomes had higher BTP (1.04 mg/l [range 0.80 to 1.49 mg/l] vs. 0.88 mg/l [range 0.68 to 1.17 mg/l], p = 0.003) and cystatin C (1.29 mg/l [range 1.00 to 1.71 mg/l] vs. 1.03 mg/l [range 0.86 to 1.43 mg/l], p = 0.001). After multivariable adjustment, both BTP (hazard ratio: 1.41, 95% confidence interval: 1.06 to 1.88; p = 0.018) and cystatin C (hazard ratio: 1.50, 95% confidence interval: 1.13 to 2.01; p = 0.006) were significant predictors of death/HF hospitalization, whereas serum creatinine, estimated glomerular filtration rate, and blood urea nitrogen were no longer significant. In patients with an estimated glomerular filtration rate >60 ml/min/1.73 m(2), elevated concentrations of BTP and cystatin C were still associated with significantly higher risk of adverse clinical events (p < 0.05). Net reclassification index analysis suggested cystatin C and BTP deliver comparable information regarding prognosis.
  
  
  CONCLUSIONS
  Among patients hospitalized with ADHF, BTP and cystatin C predict risk of death and/or HF hospitalization and are superior to standard measures of renal function for this indication.
authors.affiliation: Department of Cardiology, University Hospital Virgen de Arrixaca, Murcia, Spain.
authors.forename: Sergio
authors.initials: S
authors.lastname: Manzano-Fernández
authors.forename: James L
authors.initials: JL
authors.lastname: Januzzi
authors.forename: Miguel
authors.initials: M
authors.lastname: Boronat-Garcia
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Bonaque-González
authors.forename: Quynh A
authors.initials: QA
authors.lastname: Truong
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Pastor-Pérez
authors.forename: Carmen
authors.initials: C
authors.lastname: Muñoz-Esparza
authors.forename: Patricia
authors.initials: P
authors.lastname: Pastor
authors.forename: María D
authors.initials: MD
authors.lastname: Albaladejo-Otón
authors.forename: Teresa
authors.initials: T
authors.lastname: Casas
authors.forename: Mariano
authors.initials: M
authors.lastname: Valdés
authors.forename: Domingo A
authors.initials: DA
authors.lastname: Pascual-Figal
mesh_terms: D000208:Acute Disease; D000368:Aged; D015415:Biomarkers / Q000097:blood*; D001806:Blood Urea Nitrogen; D003404:Creatinine / Q000097:blood; D055316:Cystatin C / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D006333:Heart Failure / Q000150:complications*; D006801:Humans; D019746:Intramolecular Oxidoreductases / Q000097:blood*; D054834:Lipocalins / Q000097:blood*; D008297:Male; D011379:Prognosis; D011446:Prospective Studies; D051437:Renal Insufficiency / Q000175:diagnosis*
chemical_list: D015415:Biomarkers; D055316:Cystatin C; D054834:Lipocalins; D003404:Creatinine; D019746:Intramolecular Oxidoreductases; C022466:prostaglandin R2 D-isomerase