Blood Urea/Creatinine Ratio and Mortality in Ambulatory Patients with Heart Failure with Reduced Ejection Fraction

Background: Chronic heart failure with reduced ejection fraction (HFrEF) is associated with high mortality, and renal dysfunction is common in these patients. Blood urea/creatinine ratio (UCR) has been identified as a potential prognostic marker, reflecting both renal function and neurohormonal activity. We assessed whether a UCR ≥ 95 at discharge from an outpatient service was associated with increased mortality. Methods: This retrospective study reviewed 337 patients (age 72.7 ± 14.3 years; 64.7% Male; Mean LVEF 33.2 ± 8.9%) with HFrEF referred to the Heart Failure Nurse Service at NHS Tayside for optimisation of heart failure medication. Cox proportional hazards models were used to assess the association between UCR and all-cause mortality. Results: Receiver operating characteristic (ROC) analysis identified a UCR threshold of 95 (area under the curve AUC 0.701) as predictive of mortality. Results demonstrated that a UCR ≥ 95 was independently associated with increased mortality (HR 1.85, 95% CI 1.09–3.14, p = 0.022). A high UCR was associated with increased mortality even in patients with preserved eGFR, a group typically considered at lower risk (HR 4.03, 95% CI 1.50–10.9, p = 0.006). Conclusions: These findings suggest that UCR could be a useful addition for identifying high-risk patients who may benefit from closer monitoring and more aggressive intervention following optimisation of heart failure medication.