Abstract 248: Substance Abuse is Associated with Observation Status of Patients with Heart Failure at an Urban Academic Medical Center

Background: More than 80% of patients presenting to the emergency department (ED) with acute decompensated heart failure (ADHF) are admitted and categorized as either observation (OBS) or inpatient (IP) post discharge using Interqual criteria (severity of illness and intensity of service). Identifying patient characteristics upon admission to determine OBS or IP status may optimize hospital resource utilization. Purpose: To determine patient characteristics upon admission that are associated with the categorization (OBS vs IP) for patients with ADHF presenting to the ED of an urban academic medical center. Methods: Retrospective medical record review of 172 randomly selected adult patients from 2013 who presented to the ED with ADHF. Patients had been categorized as OBS vs IP after discharge based on Interqual Criteria. Based on the literature, we identified variables traditionally associated with an admitting diagnosis for heart failure (HF) including: symptoms (shortness of breath, paroxysmal nocturnal dyspnea, orthopnea, and lower extremity edema), physiologic measures (B-type natriuretic peptide and blood pressure), and patient characteristics (number of co-morbidities, type of HF- HF with reduced ejection fraction vs HF with preserved ejection fraction, 30 day readmission rate, gender, ethnicity, and history of substance abuse within the past 12 months). Chi square tests and student t-tests were used to compare variables between groups. Results: Of the 172 ADHF patients, 76% (n=131) were categorized as IP and 24% (n=41) were OBS. The majority of patients were African American (n = 130, 75.6%), female (n = 101, 58.7%) and had HF with a reduced ejection fraction (n = 99, 57.6%). There were no significant differences between the OBS and IP groups in terms of symptoms, B-type natriuretic peptide levels, blood pressure, number of co-morbidities, type of HF, 30 day readmission rate, gender, ethnicity, or socio-demographic characteristics. A history of substance abuse was more common among the OBS group versus the IP group ( p = 0.013). Conclusions: In this single center retrospective medical record review comparing the categorization of patients presenting to the ED with ADHF as OBS vs IP, we found no difference in the traditional clinical variables between groups. However, a history of substance abuse was associated with the patient being categorized as OBS. Substance abuse may be an important non-traditional variable to consider in resource utilization.