Clinical implications of the blood urea nitrogen/creatinine ratio in heart failure and their association with haemoconcentration

ESC Heart Fail. 2019 Dec;6(6):1274-1282. doi: 10.1002/ehf2.12531. Epub 2019 Dec 9.

Abstract

Aims: The blood urea nitrogen (BUN)/creatinine ratio is a strong prognostic indicator in patients with acute decompensated heart failure (ADHF). However, the clinical impact of a high BUN/creatinine ratio at discharge with respect to renal dysfunction, neurohormonal hyperactivity, and different responsiveness to decongestion therapy remains unclear. Herein, we examined (i) the predictive value of a high BUN/creatinine ratio at discharge and (ii) its haemoconcentration-dependent effects, in patients with ADHF.

Methods and results: The West Tokyo Heart Failure registry was a multicentre, prospective cohort registry-based study that enrolled patients hospitalized with a diagnosis of ADHF. The endpoint was post-discharge all-cause death. Based on the degree of haemoconcentration, patients (n = 2090) were divided into four subcategories. In multivariate proportional hazard analyses, a higher BUN/creatinine ratio was independently associated with higher all-cause mortality in the total population and in the extreme haemodilution (ΔHaemoglobin ≤ -0.9 g/dL) and haemoconcentration (0.8 g/dL ≤ ΔHaemoglobin) subcategories, but not in the modest haemodilution/haemoconcentration subcategories.

Conclusions: A higher BUN/creatinine ratio at discharge was independently associated with higher post-discharge all-cause mortality in patients with ADHF. The predictive value of a high BUN/creatinine ratio at discharge was haemoconcentration dependent and may be an unfavourable predictor in patients showing excessive haemoconcentration and haemodilution, but not in those showing modest haemoconcentration/haemodilution.

Keywords: Acute decompensated heart failure; Blood urea nitrogen/creatinine ratio; Haemoconcentration; Haemodilution.

Publication types

  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Blood Urea Nitrogen*
  • Creatinine / blood*
  • Female
  • Heart Failure* / blood
  • Heart Failure* / diagnosis
  • Heart Failure* / epidemiology
  • Heart Failure* / mortality
  • Hemoglobins / analysis
  • Humans
  • Male
  • Middle Aged
  • Patient Discharge
  • Prospective Studies
  • Registries

Substances

  • Hemoglobins
  • Creatinine