Urine N-Terminal Pro B-Type Natriuretic Peptide is Predictive of Heart Failure-Related Emergency Department Visits

AIMS: Emergency department (ED) visits for decompensated heart failure (HF) are frequent and associated with poor long-term outcomes in patients with HF. Serum N-terminal pro b-type natriuretic peptide (NT-proBNP) is widely used to assist diagnosis and predict clinical outcomes in HF patients. Few studies have investigated the use of urine NT-proBNP as an HF biomarker. This study aims to assess the value of urine NT-proBNP for predicting ED visits for decompensated HF as compared with that of serum NT-proBNP. METHODS AND RESULTS: This study included 122 HF patients with reduced left ventricular ejection fraction (<50%). Serum and urine NT-proBNP levels were measured. Baseline data included demographics, comorbidities, and co-medications. Medical records were used to determine the incidence of visits to the ED for decompensated HF during the 3 months following the last visit. We observed significantly higher levels of both serum and urine NT-proBNP in patients with subsequent ED visits than in those without. Multivariate logistic regression analysis showed that urine NT-proBNP/creatinine ratio (OR, 1.031; 95% CI, 1.001-1.061; P = 0.046) but not serum NT-proBNP was an independent factor associated with subsequent ED visits. According to receiver-operating characteristic-area under the curve analysis, the optimal cut-off value of urine NT-proBNP/creatinine ratio for predicting subsequent heart-failure related ED visits was 0.272 pg/μg Cr (area under the curve, 0.675; P = 0.011). CONCLUSIONS: For HF patients with reduced left ventricular ejection fraction, a single measurement of urinary NT-proBNP/creatinine ratio is predictive of subsequent ED visits for decompensated HF. This non-invasive and easy measurement may be a clinically useful tool for monitoring clinical outcomes and identifying a subset of patients at higher risk of ED visits within a short time.