Neighborhood-level out-of-hospital cardiac arrest risk and the impact of local CPR interventions.

Introduction: It is unclear how best to identify "high-risk" areas for out-of-hospital cardiac arrest (OHCA) and if neighborhood-level interventions improve bystander cardiopulmonary resuscitation (BCPR). Our objectives were to 1) identify and compare community characteristics between high and low-risk neighborhoods; and 2) examine change in BCPR after a targeted hands-only CPR intervention.

Methods: This was a cross-sectional analysis of OHCA events in Franklin County, Ohio between 1/1/2010-12/31/2017. Adult (≥18 years) OHCAs in a non-healthcare setting with emergency medical services resuscitation attempted were included. High-risk neighborhoods based on OHCA incidence and BCPR rates were identified using global Empirical Bayes, Local Moran's I, and spatial scan statistic. We compared characteristics of high and low-risk neighborhoods and examined change in BCPR.

Results: From the 3,841 included OHCAs, the mean adjusted OHCA incidence per census tract was 0.81 per 1,000, BCPR rate was 37.2%, and survival to hospital discharge was 11.5%. Of the 35 census tracts identified as high-risk, ten persisted from previous work. OHCA incidence was higher in high-risk neighborhoods (1.30 per 1,000 vs. 0.73, p < 0.001) and BCPR rates were lower (30.2% vs. 38.5%, p < 0.001). There were significant differences in characteristics between high and low-risk neighborhoods (e.g., Black population: 45.3% vs. 25.7%, p < 0.001). The neighborhoods targeted for the community education intervention had similar pre- and post-intervention BCPR rates.

Conclusions: Demographic and socioeconomic characteristics differed between high- and low-risk neighborhoods. BCPR rates were lower in high-risk neighborhoods despite a targeted BCPR intervention. Educational interventions may be necessary, but not sufficient, to improve OHCA outcomes.