Small area variations in out-of-hospital cardiac arrest: does the neighborhood matter?

BACKGROUND The incidence and outcomes of out-of-hospital cardiac arrest vary widely across cities. It is unknown whether similar differences exist at the neighborhood level. OBJECTIVE To determine the extent to which neighborhoods have persistently high rates of cardiac arrest but low rates of bystander cardiopulmonary resuscitation (CPR). DESIGN Multilevel Poisson regression of 1108 cardiac arrests from 161 census tracts as captured by the Cardiac Arrest Registry to Enhance Survival (CARES). SETTING Fulton County, Georgia, between 1 October 2005 to 30 November 2008. MEASUREMENTS Incidence of cardiac arrest, by census tract and year and by rates of bystander CPR. RESULTS Adjusted rates of cardiac arrest varied across neighborhoods (interquartile range [IQR], 0.57 to 0.73 per 1000 persons; mean, 0.64 per 1000 persons [SD, 0.11]) but were stable from year to year (intraclass correlation, 0.36 [95% CI, 0.26 to 0.50]; P < 0.001). Adjusted bystander CPR rates also varied by census tract (IQR, 19% to 29%; mean, 25% [SD, 10%]). LIMITATION Analysis was based on data from a single county. CONCLUSION Surveillance data can identify neighborhoods with a persistently high incidence of cardiac arrest and low rates of bystander CPR. These neighborhoods are promising targets for community-based interventions. PRIMARY FUNDING SOURCE Robert Wood Johnson Foundation Clinical Scholars Program, National Institutes of Health, and Centers for Disease Control and Prevention.