title: Determinants of absolute and relative exercise-induced changes in B-type natriuretic peptides.
abstract: BACKGROUND
  Exercise is associated with changes in circulating B-type natriuretic peptide (BNP) and N-terminal-proBNP (NT-proBNP). However, the biological relevance of this phenomenon is poorly examined. We sought to assess determinants of absolute (Δ) and relative (Δ%) exercise-induced changes in BNP and NT-proBNP.
  
  
  METHODS
  BNP (n = 418) and NT-proBNP (n = 478) at rest and peak exercise were measured in patients undergoing symptom-limited cycle ergometer tests. Multivariate logistic regression was performed to identify predictors of high ΔBNP/ΔNT-proBNP and high ΔBNP/Δ%NT-proBNP defined as their highest quartiles (Q4).
  
  
  RESULTS
  The median (interquartile range) ΔBNP and ΔNT-proBNP was 12 (0-28) pg/ml and 7 (2-21) pg/ml respectively, and Δ%BNP and Δ%NT-proBNP was 21 (0-46) % and 7 (3-12) % respectively. Higher BNP [odds ratio (OR) 3.92 per ln unit; p < 0.001] or NT-proBNP [OR 4.88 per ln unit; p<0.001] at rest was the strongest predictor of ΔBNP in Q4 (≥ 28 pg/ml) or ΔNT-proBNP in Q4 (≥ 21 pg/ml). In contrast, higher maximal work rate expressed as the percentage of the predicted value (OR 1.015 per %; p = 0.007) was the only independent predictor of Δ%BNP in Q4 (≥ 46%), and lower resting heart rate (OR 0.97 per bpm; p = 0.001) and lower age (OR 0.95 per year; p = 0.001) were the only independent predictors of Δ%NT-proBNP in Q4 (≥ 12%).
  
  
  CONCLUSIONS
  Higher ΔBNP and ΔNT-proBNP primarily reflected higher BNP and NT-proBNP plasma levels at rest. In contrast, higher Δ%BNP and Δ%NT-proBNP were associated with several prognostically favorable features, indicating that higher Δ%BNP and Δ%NT-proBNP may be markers of health rather than disease.
authors.affiliation: Baker IDI Heart and Diabetes Institute and Heart Center, Alfred Hospital, Melbourne, Victoria, Australia. micha.maeder@bluewin.ch
authors.forename: Micha T
authors.initials: MT
authors.lastname: Maeder
authors.forename: Daniel
authors.initials: D
authors.lastname: Staub
authors.forename: Yves
authors.initials: Y
authors.lastname: Surnier
authors.forename: Tobias
authors.initials: T
authors.lastname: Reichlin
authors.forename: Markus
authors.initials: M
authors.lastname: Noveanu
authors.forename: Tobias
authors.initials: T
authors.lastname: Breidthardt
authors.forename: Mihael
authors.initials: M
authors.lastname: Potocki
authors.forename: Nora
authors.initials: N
authors.lastname: Schaub
authors.forename: David
authors.initials: D
authors.lastname: Conen
authors.forename: Christian
authors.initials: C
authors.lastname: Mueller
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D015331:Cohort Studies; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000097:blood* / Q000175:diagnosis* / Q000503:physiopathology; D020097:Natriuretic Peptide, Brain / Q000096:biosynthesis / Q000097:blood*; D010446:Peptide Fragments / Q000096:biosynthesis / Q000097:blood*; D011498:Protein Precursors / Q000096:biosynthesis / Q000097:blood*
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; D011498:Protein Precursors; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain