title: A combined-biomarker approach to clinical phenotyping renal dysfunction in heart failure.
abstract: BACKGROUND
  Differentiating heart failure (HF) induced renal dysfunction (RD) from intrinsic kidney disease is challenging. It has been demonstrated that biomarkers such as B-type natriuretic peptide (BNP) or the blood urea nitrogen to creatinine ratio (BUN/creat) can identify high- vs low-risk RD. Our objective was to determine if combining these biomarkers could further improve risk stratification and clinical phenotyping of patients with RD and HF.
  
  
  RESULTS
  A total of 908 patients with a discharge diagnosis of HF were included. Median values were used to define elevated BNP (>1296 pg/mL) and BUN/creat (>17). In the group without RD, survival was similar regardless of BNP and BUN/creat (n = 430, adjusted P = .52). Similarly, in patients with both a low BNP and BUN/creat, RD was not associated with mortality (n = 250, adjusted hazard ratio [HR] = 1.0, 95% confidence interval [CI] 0.6-1.6, P = .99). However, in patients with both an elevated BNP and BUN/creat those with RD had a cardiorenal profile characterized by venous congestion, diuretic resistance, hypotension, hyponatremia, longer length of stay, greater inotrope use, and substantially worse survival compared with patients without RD (n = 249, adjusted HR = 1.8, 95% CI 1.2-2.7, P = .008, P interaction = .005).
  
  
  CONCLUSIONS
  In the setting of decompensated HF, the combined use of BNP and BUN/creat stratifies patients with RD into groups with significantly different clinical phenotypes and prognosis.
authors.affiliation: Department of Internal Medicine and Program of Applied Translational Research, Yale University School of Medicine, New Haven, Connecticut. Electronic address: jeffrey.testani@yale.edu.
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Testani
authors.affiliation: University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors.forename: Kevin
authors.initials: K
authors.lastname: Damman
authors.affiliation: Department of Internal Medicine, Medical University of South Carolina, Charleston, South Carolina.
authors.forename: Meredith A
authors.initials: MA
authors.lastname: Brisco
authors.affiliation: Department of Internal Medicine and Program of Applied Translational Research, Yale University School of Medicine, New Haven, Connecticut.
authors.forename: Susan
authors.initials: S
authors.lastname: Chen
authors.affiliation: Department of Internal Medicine and Program of Applied Translational Research, Yale University School of Medicine, New Haven, Connecticut.
authors.forename: Olga
authors.initials: O
authors.lastname: Laur
authors.affiliation: Department of Internal Medicine and Program of Applied Translational Research, Yale University School of Medicine, New Haven, Connecticut.
authors.forename: Alexander J
authors.initials: AJ
authors.lastname: Kula
authors.affiliation: Section of Heart Failure and Cardiac Transplantation, Cleveland Clinic, Cleveland, Ohio.
authors.forename: W H Wilson
authors.initials: WH
authors.lastname: Tang
authors.affiliation: Department of Internal Medicine and Program of Applied Translational Research, Yale University School of Medicine, New Haven, Connecticut.
authors.forename: Chirag
authors.initials: C
authors.lastname: Parikh
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D001806:Blood Urea Nitrogen; D059347:Cardio-Renal Syndrome / Q000175:diagnosis* / Q000401:mortality; D015331:Cohort Studies; D016001:Confidence Intervals; D003404:Creatinine / Q000652:urine*; D005260:Female; D005919:Glomerular Filtration Rate; D006333:Heart Failure / Q000150:complications* / Q000175:diagnosis / Q000401:mortality; D006785:Hospitals, University; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D011379:Prognosis; D051437:Renal Insufficiency / Q000150:complications* / Q000175:diagnosis* / Q000401:mortality; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D015996:Survival Rate
chemical_list: D015415:Biomarkers; D003404:Creatinine
keywords: BNP; Cardiorenal syndrome; blood urea nitrogen to creatinine ratio; decompensated heart failure