People who experience sudden cardiac arrest are less likely to receive CPR from bystanders and less likely to survive, when they collapse in neighborhoods with large Latino populations, according to a large, new study to be presented in Chicago at the American Heart Association’s Resuscitation Science Symposium 2018, an international conference highlighting the best in cardiovascular resuscitation research.

Sudden cardiac arrest occurs when the heart abruptly stops pumping blood due to an electrical malfunction. Almost 4 in 10 such cases are witnessed by a bystander who is not an emergency medical services provider, according to American Heart Association statistics.

The American Heart Association recommends that bystanders who see a teenager or adult suddenly collapse call 9-1-1 and administer “Hands-Only CPR”—chest compressions without rescue breaths until help arrives. Fewer than 12% of people survive an out-of-hospital cardiac arrest.

“Survival is low, but prompt delivery of CPR by a lay bystander can significantly improve outcomes,” said Audrey L. Blewer, PhD, MPH, lead study author and assistant director of educational programs at the Center for Resuscitation Science at Penn Medicine.

The study examined records of 18,544 cardiac arrests in adults between 2011-2015 that were not witnessed by emergency personnel and occurred outside a hospital. Researchers compared neighborhoods according to US Census classifications based on percentage of Latino residents. They found:

• Overall, bystanders provided CPR in 37% of cases.
• In neighborhoods where Latinos accounted for less than one-quarter of the population, bystanders provided CPR in 39% of the cardiac arrests in the study.
• In neighborhoods where Latinos made up more than three-quarters of the people, CPR was given in just 27% of such incidents.
• Among all patients in the study, Latinos were 27% less likely than whites to receive CPR.
• Cardiac arrest victims in the most heavily Latino-populated neighborhoods were almost 40% less likely to survive until discharge from the hospital.

The findings considered differing levels of education and income among the neighborhoods, Blewer said.

The data were from the Resuscitation Outcomes Consortium, a clinical trial network of emergency medical service systems and hospitals across the United States and Canada. Consortium figures suggest out-of-hospital cardiac arrest occurs in about 111 out of every 100,000 individuals, or more than 350,000 people in the United States each year.

The US Latino population, which in mid-2016 numbered nearly 58 million, is expected to nearly double over the next 40 years, according to the US Census Bureau. Targeting Latino communities is a vital part of efforts to reduce US deaths from sudden cardiac arrest, Blewer said. AHA Emergency Cardiovascular Care goals include doubling out-of-hospital bystander CPR response rates this decade, from 31% to 62% by 2020.

“We need to think about targeting communities with lower rates of bystander CPR with simple, effective CPR training,” Blewer said. “We also need to think about public messaging around CPR—are we communicating our message clearly and effectively to all communities? Have we thought about public messaging of pushing hard and fast in the center of the chest? Is this getting disseminated to all racial/ethnically diverse communities?”

Research has found that counties with high proportions of Latino residents are more likely to have low rates of CPR training.

Recent work by Blewer and her colleagues indicated that Latinos were less likely than blacks or whites to be trained in the use of automated external defibrillator (AEDs), a portable, lifesaving device that can be used by people without medical training to deliver an electric shock to the heart.

Co-authors are Shaun McGovern, BS, EMT-B; Robert Schmicker, MS; Susanne May, PhD, MS; Laurie Morrison, MD; Tom Aufderheide, MD; Mohamud Daya, MD, MS; Ahamed Idris, MD; Clifton Callaway, MD, PhD; Peter Kudenchuk, MD; Gary Vilke, MD; and Benjamin S. Abella, MD, M.Phil. Author disclosures are on the abstract.

A Mentored Clinical and Population Grant from the American Heart Association funded the study.