Geospatial analysis for targeting out-of-hospital cardiac arrest intervention

Bystander cardiopulmonary resuscitation (BCPR) provides an opportunity for decreasing cardiac mortality. Rates of out-of-hospital cardiac arrest (OHCA) in which resuscitation was performed vary within cities and across demographics.

To identify contiguous geographic census tracts with high OHCA, low BCPR rates and high-risk demographics to effectively target culturally appropriate community-based intervention planning.

In 2012, a cohort of 11,389 emergency medical services (EMS) OHCA cases from Houston TX (2004-2011) was linked to census tracts. Multivariable logistic regression analyses were used to identify demographics of contiguous geographic census tracts with the highest OHCA rates. Within these tracts, BCPR rates were evaluated. The combination of information was used to develop a plan to better target interventions.

Contiguous census tracts of high OHCA rates were identified; the average rate per 100,000 within versus outside the identified tracts is 106.0 (SD 23.7) to 55.8 (SD 19.7). Tracts with a low BCPR rate (37.7%) relative to a high OHCA rate were identified. In a separate analysis, individuals at highest relative risk of OHCA were found to be African Americans, to have low income or education levels, and to be older individuals. For every 1% increase in African Americans in a census tract, there is an increase of 2.7% in the relative risk of the census tract belonging to a high-OHCA-rate region (95% CI=2.0%, 3.5%).

Geospatial analysis can provide important information on the contiguous areas of high OHCA rates and low BCPR rates with the aim of more effectively targeting interventions and ultimately decreasing cardiac deaths.