Title: Racial and Ethnic Differences in Emergency Medical Services Interventions for Out-of-Hospital Cardiac
Arrest
Abstract: Out-of-hospital cardiac arrest (OHCA) represents a significant public health concern, affecting an
estimated 347,000 individuals in the United States annually. Despite various efforts, the mortality rate after
OHCA remains distressingly high, with a mere 9.0% of patients surviving to hospital discharge. Prior research
has highlighted racial and ethnic disparities in patient outcomes following OHCA; notably, Black and Hispanic
patients display lower rates of survival to hospital discharge compared to White patients. However, the
underlying reasons for the disparities have yet to be fully explored. In particular, the influence of racial and
ethnic differences on resuscitation practices employed by emergency medical services (EMS) personnel
remains unclear despite the integral role of EMS in OHCA management.
To address these crucial knowledge gaps, we aim to scrutinize racial and ethnic differences (Black or Hispanic
as compared with White) in prehospital resuscitation interventions for OHCA, using the Resuscitation
Outcomes Consortium (ROC) Epidemiologic Registry, a comprehensive prospective OHCA registry at 10 sites
in North America. In this proposal, we will focus our investigation on racial and ethnic differences in three key
EMS interventions: time to defibrillations, time to epinephrine administration, and time to termination of
resuscitation (TOR). These practices are not only associated with patient outcomes after cardiac arrest but
also modifiable through educational and clinical interventions. Additionally, it remains unclear whether racial
and ethnic differences in EMS interventions diverge based on patients’ sex (intersectionality). We will evaluate
the intersectionality, assessing whether sex is an effect modifier on racial and ethnic differences in time to the
EMS interventions. Lastly, we will quantify the contribution of racial and ethnic differences in EMS interventions
to racial and ethnic disparities in survival using mediation analyses.
Our overall objective is to augment our comprehension of these potential disparities in prehospital practices
and identify modifiable areas for enhancing OHCA care. We will leverage OHCA as a representative case for
time-sensitive conditions, with the objective of evaluating racial and ethnic disparities in EMS practices as
potential contributors to the prevailing health inequity. Our team is comprised of experts in cardiac arrest
research, health disparities research, causal inference, and statistical modelling with extensive experience with
the ROC dataset, ensuring the feasibility of the proposed project.
We anticipate that our study will identify specific areas where interventions can be implemented to mitigate
racial and ethnic disparities in patient outcomes after OHCA and serve as a pioneering step toward the further
evaluation of health inequity in relation to other time-sensitive conditions within EMS systems.
