title: Influence of low-grade inflammation on plasma B-type natriuretic peptide levels.
abstract: OBJECTIVE
  B-type natriuretic peptide (BNP) is a cardiac hormone. The results of previous in vitro studies suggest that neurohumoral factors, and not only hemodynamic factors, may cause BNP secretion. In this study, we examined the impact of serum C-reactive protein (CRP) levels on the relationship between echocardiographic parameters and plasma BNP levels in patients with cardiovascular diseases.
  
  
  METHODS
  The study population comprised 417 patients who visited our cardiovascular unit with a problem. Both blood sampling and echocardiography were performed within one month.
  
  
  RESULTS
  Multiple regression analysis showed that plasma BNP levels were negatively correlated with male gender, body mass index, and estimated glomerular filtration rate, and positively correlated with serum CRP levels and left ventricular end-systolic dimension (LVDs). The study population was divided into two groups based on the 75th percentile of the serum CRP levels. Single regression analysis showed that a regression line between LVDs and plasma BNP levels was steeper in the group of patients with CRP levels above the 75th percentile. Multiple regression analysis revealed that the interaction term (LVDs×CRP) was significant, which means LVDs had more impact on plasma BNP levels at higher CRP levels.
  
  
  CONCLUSIONS
  Plasma BNP levels increased with respect to the severity of cardiac dysfunction and serum CRP levels, and should therefore be considered a collective or total marker for life-threatening conditions including systemic inflammation, and not simply as a marker of cardiac dysfunction in patients with cardiovascular diseases.
authors.affiliation: Division of Cardiology, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo.
authors.forename: Terumasa
authors.initials: T
authors.lastname: Inoue
authors.forename: Makoto
authors.initials: M
authors.lastname: Kawai
authors.forename: Tokiko
authors.initials: T
authors.lastname: Nakane
authors.forename: Ayumi
authors.initials: A
authors.lastname: Nojiri
authors.forename: Kosuke
authors.initials: K
authors.lastname: Minai
authors.forename: Kimiaki
authors.initials: K
authors.lastname: Komukai
authors.forename: Takayuki
authors.initials: T
authors.lastname: Ogawa
authors.forename: Kenichi
authors.initials: K
authors.lastname: Hongo
authors.forename: Masato
authors.initials: M
authors.lastname: Matsushima
authors.forename: Michihiro
authors.initials: M
authors.lastname: Yoshimura
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000378:metabolism*; D002318:Cardiovascular Diseases / Q000097:blood* / Q000175:diagnosis / Q000473:pathology*; D005260:Female; D006801:Humans; D018836:Inflammation Mediators / Q000097:blood / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers; D018836:Inflammation Mediators; D020097:Natriuretic Peptide, Brain; D002097:C-Reactive Protein