title: Superior predictive value for NTproBNP compared with high sensitivity cTnT in dialysis patients: a pilot prospective observational study.
abstract: OBJECTIVE
  The clinical utility of the new biomarker, high sensitivity cardiac T troponin (hs-cTnT) is still unclear in dialysis patients. Furthermore, the prognostic value of combining N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) and hs-cTnT has not been explored so far. The objective of this pilot study was to determine the utility of hs-cTnT alone versus hs-cTnT in combination with NT-proBNP for predicting death in a stable hemodialysis cohort.
  
  
  METHODS
  A prospective observational pilot study including 98 chronic asymptomatic hemodialysis patients with a follow up period of 24 months was designed. The cut-off values for NT-proBNP and hs-cTnT were calculated using receiver operating characteristic (ROC) analysis, using mortality as an end-point. Based on the cut-off values, the cohort was divided into four groups. Group 1--NT-proBNP < 14275 pg/ml and hs-cTnT < 69.48 ng/l; group 2--NT-proBNP < 14275 pg/ml and hs-cTnT > 69.48 ng/l; group 3--NT-proBNP > 14275 pg/ml and hs-cTnT < 69.48 ng/l; group 4--NT-proBNP > 14275 pg/ml and hs-cTnT > 69.48 ng/l. Survival for each group was determined using the Kaplan-Meier method and Cox regression analysis.
  
  
  RESULTS
  During the follow-up period 16 patients died. According to the ROC curves analysis, the cut-off point for hs-cTnT and for NT-proBNP were 69.43 ng/l (AUC = 0.618; p = 0.04) and 14275 pg/ml (AUC = 0.722; p = 0.003), respectively. In univariate Cox analysis, both hs-cTnT (HR = 3.34; p = 0.016) and NT-proBNP (HR = 5.94; p = 0.01) were predictors of death. In the multivariable Cox proportional hazards model, only NT-pro-BNP levels above the cut-off value remained an independent predictor of all-cause mortality. The combined elevation of both biomarkers did not improve significantly the prognostic value compared with NT-proBNP alone (HR = 6.15 versus HR =4 .78; p = 0.338).
  
  
  CONCLUSIONS
  NT-pro-BNP is a strong predictor of overall mortality in asymptomatic hemodialysis patients. The addition of hs-cTnT did not improve the prognostic accuracy compared with NT proBNP alone.
authors.affiliation: Nephrology Clinic, Dialysis and Renal Transplant Center, C.I. Parhon University Hospital, Gr. T. Popa University of Medicine and Pharmacy, Iasi, Romania.
authors.forename: Luminita
authors.initials: L
authors.lastname: Voroneanu
authors.forename: Dimitrie
authors.initials: D
authors.lastname: Siriopol
authors.forename: Ionut
authors.initials: I
authors.lastname: Nistor
authors.forename: Mugurel
authors.initials: M
authors.lastname: Apetrii
authors.forename: Simona
authors.initials: S
authors.lastname: Hogas
authors.forename: Mihai
authors.initials: M
authors.lastname: Onofriescu
authors.forename: Adrian
authors.initials: A
authors.lastname: Covic
mesh_terms: D000368:Aged; D001823:Body Composition; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D018450:Disease Progression; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood / Q000401:mortality / Q000628:therapy; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D010865:Pilot Projects; D011237:Predictive Value of Tests; D011446:Prospective Studies; D006435:Renal Dialysis / Q000379:methods*; D016019:Survival Analysis; D020107:Troponin T / Q000097:blood*; D059289:Vascular Stiffness
chemical_list: D010446:Peptide Fragments; D020107:Troponin T; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain