title: Prognostic impact of blood urea nitrogen changes during hospitalization in patients with acute heart failure syndrome.
abstract: BACKGROUND
  Elevated blood urea nitrogen (BUN) observed in patients hospitalized for acute heart failure syndrome (AHFS) may represent increased neurohumoral activation. The purpose of this study was to examine the prognostic impact of BUN changes during hospitalization on the long-term prognosis of AHFS patients.
  
  
  RESULTS
  The Tohoku Acute Heart Failure Registry (n=497) is a multicenter retrospective cohort study enrolling AHFS patients who were admitted in 2007. The 337 survivors (mean age, 76 years; 52% male) were divided into 3 groups according to tertiles of BUN change during hospitalization: Decreased (D-BUN, ΔBUN (BUN level at discharge-BUN level at hospitalization)≤-1.63 mg/dl, n=112); Unchanged (U-BUN, ΔBUN-1.64 to 5.73 mg/dl, n=113); Increased (I-BUN, ΔBUN>5.73 mg/dl, n=112). The D-BUN group had higher prevalence of lowest glomerular filtration rate during hospitalization, whereas the I-BUN group had higher systolic blood pressure. During a median follow-up period of 2.3 years after discharge, the Kaplan-Meier curve showed that D-BUN and I-BUN had worse prognosis compared with U-BUN. Multivariable logistic model showed that all-cause death was more frequent in I-BUN (hazard ratio, 2.94; 95% confidence interval, 1.51-5.73; P<0.001). Subgroup analysis revealed that BUN increase during hospitalization was associated with all-cause death, regardless of renal function.
  
  
  CONCLUSIONS
  AHFS patients with a BUN increase during hospitalization have worse long-term prognosis, independent of renal function.
authors: Departments of Cardiovascular Medicine and Evidence-based Cardiovascular Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan.
authors: Masanobu
authors: M
authors: Miura
authors: Yasuhiko
authors: Y
authors: Sakata
authors: Kotaro
authors: K
authors: Nochioka
authors: Jun
authors: J
authors: Takahashi
authors: Tsuyoshi
authors: T
authors: Takada
authors: Satoshi
authors: S
authors: Miyata
authors: Tetsuya
authors: T
authors: Hiramoto
authors: Kan-ichi
authors: K
authors: Inoue
authors: Kenji
authors: K
authors: Tamaki
authors: Nobuyuki
authors: N
authors: Shiba
authors: Hiroaki
authors: H
authors: Shimokawa
mesh_terms: D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure; D001806:Blood Urea Nitrogen; D005260:Female; D005919:Glomerular Filtration Rate; D006333:Heart Failure / Q000097:blood* / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology; D006760:Hospitalization; D006801:Humans; D007564:Japan; D053208:Kaplan-Meier Estimate; D007668:Kidney / Q000503:physiopathology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D012042:Registries; D012189:Retrospective Studies; D012307:Risk Factors; D013577:Syndrome; D013599:Systole; D013997:Time Factors
chemical_list: D015415:Biomarkers