Blood Urea Nitrogen is a Better Prognostic Predictor than Creatinine in Patients with Acute Decompensated Heart Failure - The 65th Annual Conference of the Israel Heart Society & The Israel Society of Cardiothoracic Surgery, 24-25 April 2018

Johad Khoury Pulmonary Division, Lady Davis Carmel Medical Center, Haifa, Israel Adi Elias Department of Internal Medicine, Rambam Health Care Campus, Haifa, Israel Yoav Stabholz Department of Internal Medicine, Rambam Health Care Campus, Haifa, Israel Amjad Mousa Department of Internal Medicine, Rambam Health Care Campus, Haifa, Israel Tanya Mashiach Biostatistics Unit, Rambam Health Care Campus, Haifa, Israel Doron Aronson Heart Institute, Rambam Health Care Campus, Haifa, Israel Ruth & Bruce Rappaport Faculty of Medicine, Technion, Israel Institute of Technology, Haifa, Israel Zaher Azzam Department of Internal Medicine, Rambam Health Care Campus, Haifa, Israel Ruth & Bruce Rappaport Faculty of Medicine, Technion, Israel Institute of Technology, Haifa, Israel

Introduction: Acute Decompensated Heart Failure (ADHF) is the leading cause of hospitalizations for elderly patients. The 5 year-mortality of patients with heart failure (HF) is 50%. Therefore, it is vital to investigate a number of bedside prognostic parameters that aid in assessing the prognosis of patients with ADHF. Cardio-renal syndrome is considered an important predictor of prognosis in ADHF. Although blood urea nitrogen (BUN) is known to be associated with poor outcome of ADHF patients; however, little is known about its contribution as compared to other renal function. Furthermore; the effect of BUN changes during hospital stay is another prognostic predictor that has not been fully investigated.

Aims: To compare the contribution of BUN as compared with creatinine on 90-days all-cause mortality in ADHF patients. To investigate the significance of BUN changes during hospital stay on 90-days mortality.

Methods & Results: A retrospective study included patients with primary diagnosis of ADHF who were admitted to Rambam Health Care Campus between Jan 1, 2007 & Dec 31, 2016. 4487 Pts were hospitalized with the primary diagnosis of ADHF. Diagnosis was based on the European Society of Cardiology criteria. Mean age 74 ± 12 years; 54% Male; length of stay 7.7 ± 9.5 days. Patients were categorized into 4 groups as following: 1) Normal BUN on admission and discharge (< 20 mg/dl), 2) Elevated BUN on admission and normal on discharge; 3) Normal BUN on admission and elevated on discharge and 4) Both elevated BUN. The 90-days mortality was 5.2%, 12%, 13.4% and 22.3% respectively. The discrimination capacity of BUN and creatinine was tested using AUC_ROC and found to be 0.68 and 0.62 respectively (P = 0.001).

Conclusions: In ADHF patients, BUN is a stronger predictor of mortality than creatinine. Abnormal BUN levels during hospital stay predicts a worse prognosis.