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

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 (DeltaHaemoglobin