Abstract P268: Hospital Transfer of Ischemic Stroke Patients: Prevalence and Outcomes

Abstract

BACKGROUND Little is known about transfers of patients across hospitals; inpatient outcome evaluation (report card) protocols are inconsistent in how transfers are accounted. For patients admitted for ischemic stroke in Massachusetts (MA), we estimated prevalence of transfers across hospitals, over time, and differences in inpatient mortality rates compared to patients not transferred. METHODS Discharge and American Hospital Association data were merged for all hospitalizations (2004-09) for ischemic stroke among adults (N=49,789) in all MA acute care hospitals (N=67). We linked all ischemic stroke hospitalizations with preceding and subsequent hospitalizations to obtain ischemic stroke episodes. A transfer was defined as an episode with >=2 hospitalizations such that discharge date for one coincided with admission date for another. We compared transferred and untransferred patients (episodes) in terms of patient risk factors for stroke, hospital characteristics and year. We also compared risk-adjusted inpatient mortality difference for transferred patients using a logistic regression model adjusting for patient demographics and clinical risk factors. RESULTS We identified 47,212 ischemic stroke episodes, of which 9.5% involved a transfer. This rate did not vary significantly during 2004-09. Blacks had higher transfer rates (13%; p<0.001) than Whites (9.3%) and Hispanics (9.6%). Weekend admission did not increase the risk of transfer. Transferred patients had significantly higher prevalence of risk factors for inpatient mortality: atrial fibrillation, hypertension, diabetes mellitus, heart failure and coronary heart disease. Risk-adjusted inpatient mortality among transferred patients was 26% higher than for untransferred patients (9.7% versus 7.3%; p<0.001). While transfer rates were higher for non-teaching and safety-net hospitals, and for hospitals with smaller general care and ICU bed size, substantial numbers of transfers occurred across all hospital types. CONCLUSIONS 9.5% of patients admitted for ischemic stroke experienced a hospital transfer, and were at higher risk for inpatient mortality. Further study needs to explore causal pathways linking hospital transfers and risk of adverse stroke inpatient outcomes.