Higher Walk Score Associated With Higher Rates of Bystander AED Use in Street-Level Cardiac Arrest

Introduction: Bystander CPR (BCPR) and AED use are crucial life-saving measures in out-of-hospital cardiac arrest (OHCA). OHCA occurring in low-income black neighborhoods are less likely to receive bystander assistance. In addition to socioeconomic disparities, characteristics of the built environment may also contribute to large variation in BCPR and bystander AED rates. Hypothesis: We hypothesized that pedestrian-friendly spaces have higher rates of BCPR and bystander AED use. Methods: Using the Cardiac Arrest Registry to Enhance Survival, we studied OHCA occurring in street/highway locations in the US in 2016. We excluded cardiac arrests that were witnessed by a 911 responder. Each incident address was assigned a 0-100 Walk Score® using an open-source algorithm and linked to census tract race and income data. We analyzed the relationship between Walk Score and key elements of bystander behavior: witness of arrest, provision of BCPR, and use of AED. Results: Of 3225 OHCA, 1666 (51.7%) were witnessed, 934 (29.0%) received BCPR, and 165 (5.1%) used an AED. After adjusting for age, gender, neighborhood median household income, and neighborhood percent black, every 10-point increase in Walk Score was associated with higher odds of bystander AED use (OR, 1.23; 95% CI, 1.14 to 1.32) but lower odds of witnessed arrest (OR, 0.95; 95% CI, 0.93 to 0.97) and BCPR (OR, 0.92; 95% CI, 0.90 to 0.95) (Table). Lower neighborhood household income predicted less BCPR and AED use; higher neighborhood black composition also predicted less BCPR. Conclusions: After adjusting for neighborhood-level race and income, OHCA occurring in walkable areas had higher rates of bystander AED use but lower rates of witnessed arrest and BCPR. The effects of built environments on bystander behavior and AED availability warrant closer investigation.