title: Plasma B-type natriuretic peptide level predicts kidney prognosis in patients with predialysis chronic kidney disease.
abstract: BACKGROUND
  As a cardiorenal syndrome, there is a dynamic interplay between the heart and the kidney. We conducted a prospective study to evaluate the prognostic impact of plasma B-type natriuretic peptide (BNP) level, a cardiac biomarker, on the long-term kidney prognosis in chronic kidney disease (CKD) patients.
  
  
  METHODS
  We prospectively enrolled 508 patients with CKD Stages 3, 4 and 5 not on dialysis, from a single nephrology department between 2004 and 2010. The exclusion criteria were over 90 years of age, malignancy, active infection, low cardiac ejection fraction and rapid progressive glomerulonephritis. Relationships between BNP and kidney end point [defined as doubling of baseline serum creatinine and end-stage kidney disease (ESKD) requiring kidney replacement therapy] were measured using Cox models for case-mix and laboratory variables.
  
  
  RESULTS
  The final analysis covered 485 participants with no loss to follow-up. The median follow-up period was 3.2 years. Two hundred and twenty-eight of the 485 patients reached ESKD requiring dialysis, and baseline serum creatinine levels doubled in another 31. The kidney end point was significantly poorer among patients with plasma BNP levels above, compared with below a cut-off value of 86.1 pg/mL indicated from receiver operating characteristic analysis. Multivariable Cox regression analysis identified the common logarithm BNP as a predictor of kidney end point (adjusted hazard ratio 1.78, 95% CI: 1.28-2.46, P < 0.01).
  
  
  CONCLUSIONS
  Elevation of BNP level is associated with an increased risk for accelerated progression of CKD ultimately to ESKD. Monitoring the BNP level could be helpful in the management of combined heart and kidney disease.
authors.affiliation: Department of Nephrology, Rinku General Medical Center, Osaka, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Yasuda
authors.forename: Tomonori
authors.initials: T
authors.lastname: Kimura
authors.forename: Koichi
authors.initials: K
authors.lastname: Sasaki
authors.forename: Yoshitsugu
authors.initials: Y
authors.lastname: Obi
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Iio
authors.forename: Masaya
authors.initials: M
authors.lastname: Yamato
authors.forename: Hiromi
authors.initials: H
authors.lastname: Rakugi
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Isaka
authors.forename: Terumasa
authors.initials: T
authors.lastname: Hayashi
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D018450:Disease Progression; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood / Q000209:etiology; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D006435:Renal Dialysis; D051436:Renal Insufficiency, Chronic / Q000097:blood*; D012307:Risk Factors
chemical_list: D015415:Biomarkers; D020097:Natriuretic Peptide, Brain