Abstract 127: The Influence of Neighborhood on Emergency Medical Services Use for Acute Stroke - A Population Based Cross Sectional Study

Abstract

Introduction: The identification of neighborhood level factors that are associated with use of EMS for acute stroke could identify novel targets for interventions to improve EMS activation and access to stroke treatment. Objective: To investigate the association between neighborhood level factors and use of EMS for acute stroke. Methods: We identified 2905 neurologist-adjudicated cases of ischemic stroke and intracerebral hemorrhage that presented to the emergency department in the bi-ethnic Brain Attack Surveillance in Corpus Christi stroke surveillance project (2000-2008). Cases were geocoded by home address and assigned to census tracts (proxies for neighborhoods). Clinical information and use of EMS were abstracted from medical records. Census tract data were obtained from the 2000 US Census and the Corpus Christi Police Department. The association of census tract level factors (frequencies of age over 65 years, violent crime, Hispanic ethnicity, and household income) with EMS use was estimated using hierarchical logistic regression after accounting for known patient-level predictors of EMS use for stroke. Results: 49% of stroke cases arrived by EMS. The proportion arriving by EMS ranged from 10% to 86% across census tracts (figure); however, in the fully adjusted model, only 0.3% (95% CI 0-1.1%) of the variance in use of EMS was explained by census tract. Violent crime level within census tract and all patient-level factors (except history of stroke/TIA) were associated with greater EMS use (table). Higher median income and older average age of census tract residents were associated with lower EMS use. Conclusions: While some neighborhood-level factors were associated with EMS use, nearly all variability in EMS use for stroke was explained by patient-level factors. In this community, attempts to increase EMS use should target individuals that are less likely to use EMS, such as younger adults, women, and Mexican Americans, rather than entire neighborhoods.