A 55 year-old man collapses on a city street.
We know that he’s more likely to survive if bystanders act quickly to initiate cardiopulmonary resuscitation. But where is this most likely to happen? Does race and socioeconomic status play a role? In short: is a passerby more likely to give CPR in a rich, white neighborhood than a poor black neighborhood?
The answer, according to Comilla Sasson and colleagues, is yes.
Their study, “Association of Neighborhood Characteristics with Bystander-Initiated CPR,” published in this week’s issue of NEJM, analyzed surveillance data from a nationwide cardiac arrest registry to determine how a neighborhood’s income and race might affect the probability of bystander-initiated CPR.
The study included data from all 911-activated cardiac arrests in 29 states, from 2005 through 2009. This amounted to some 14,225 events that ultimately met criteria for an “out-of-hospital arrest.” The study’s primary outcome was a CPR performed by a bystander, which the investigators defined as someone not part of the 911 response team. Authors also analyzed survival to hospital admission, hospital discharge and ultimate neurologic outcome. For each neighborhood where the event took place, investigators recorded characteristics including median age, income, racial composition and education level, using U.S. Census data.
The results were striking. Ultimately, nearly one third of the patients with out-of-hospital arrest received bystander-initiated CPR. Patients were more likely to receive CPR if they were male, white and – unsurprisingly – if they arrested in a public, witnessed location. They were less likely to receive CPR if the arrest occurred in a low-income or predominantly black neighborhood. In fact, the odds of a passerby giving CPR were 50% lower in low-income black neighborhoods than high-income non-black neighborhoods.
Did this matter? The data suggest that it does. While only 8 percent of the population survived to hospital discharge, those with bystander-initiated CPR were more likely to survive, and to leave the hospital with a better neurologic outcome. Furthermore, the makeup of the neighborhood where the arrest occurred might only be one layer of the problem. The study data suggest that blacks and Hispanics were, in fact, less likely than whites to receive CPR initiated by a bystander regardless of the neighborhood in which the arrest took place.
Of course, describing an imbalance is only a first step. The authors argue that this study should fuel further educational efforts targeting CPR training to the most at-risk areas. “Once the barriers to CPR training and performance are better understood,” the authors write, “it may be possible to design more linguistically appropriate and culturally sensitive CPR training programs…”