title: Long-term clinical variation of NT-proBNP in stable chronic heart failure patients.
abstract: OBJECTIVE
  Here, the aim is to assess long-term clinical variation (CV) of N-terminal pro-brain natriuretic peptide (NT-proBNP) in stable chronic heart failure (CHF) patients. The proposed use of NT-proBNP for monitoring of CHF patients will require accurate information about long-term CV of the peptide.
  
  
  RESULTS
  Medication, biochemical variables, and NYHA class were recorded at 1-year and 2-year follow-up in patients treated in our heart failure clinic. Only patients without changes in medication and the NYHA class who were not hospitalized or died in the period from first follow-up to 12 months after the second follow-up were included. A total of 78 patients fulfilled the criteria, and year-to-year CV was calculated to 30% (median) (range: 0-111%) (% changes range: -87 to 397%). Log transformation of NT-proBNP (skewed to the right) reduced the year-to-year CV to 4.7% (range: 0-22%) (% changes range: -18 to 38%).
  
  
  CONCLUSIONS
  Long-term CV of plasma concentrations of NT-proBNP in stable CHF patients is 30%, but the variation is substantial. Therefore, high long-term CV of NT-proBNP does not necessarily carry prognostic significance within the subsequent 12 months. Plasma concentrations of NT-proBNP followed a lognormal distribution, and the low CV of log(NT-proBNP) indicate that NT-proBNP levels are constant during stable conditions.
authors.affiliation: Department of Cardiology and Endocrinology, Clinic E, Frederiksberg University Hospital, Ndr. Fasanvej 57-59, DK-2000 Frederiksberg, Denmark. morten.schou@fh.hosp.dk
authors.forename: Morten
authors.initials: M
authors.lastname: Schou
authors.forename: Finn
authors.initials: F
authors.lastname: Gustafsson
authors.forename: Andreas
authors.initials: A
authors.lastname: Kjaer
authors.forename: Per R
authors.initials: PR
authors.lastname: Hildebrandt
mesh_terms: D000368:Aged; D002908:Chronic Disease; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000097:blood*; D006760:Hospitalization; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000378:metabolism*; D010446:Peptide Fragments / Q000378:metabolism*; D013997:Time Factors
chemical_list: D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain