A comprehensive, community-wide effort to teach North Carolinians to recognize cardiac arrest, perform CPR and use defibrillators did not significantly improve survival with favorable brain function for adults who suffered cardiac arrest outside a hospital, according to late-breaking science presented at the American Heart Association's Scientific Sessions 2026 in Chicago.
The five-year, randomized controlled trial, known as RACE-CARS, covered 60 counties representing more than 8.5 million residents, nearly 80% of North Carolina's population. Thirty-one counties were randomly assigned to receive the educational intervention, while 29 continued their existing cardiac arrest response practices. The findings were simultaneously published as a full manuscript in the peer-reviewed New England Journal of Medicine.
Survival was essentially unchanged: about 9% of patients in intervention communities survived to leave the hospital with favorable brain function, compared with 9.4% in communities that did not receive the program. Bystanders performed CPR in 44.8% of cardiac arrests in intervention counties versus 42.3% elsewhere, and defibrillation before EMS arrival occurred in 13.5% of cases in intervention communities compared with 15.3% in the comparison group. The study included 22,459 adults; the median age was 64, 37% were women, 33% were Black adults and 29% lived in rural areas.
The most striking signal came late. An exploratory analysis found that during the final year of the study, people who experienced out-of-hospital cardiac arrest in communities with the education program had 33% higher odds of receiving bystander CPR than those in communities outside the program, suggesting that sustained community outreach may take years to change behavior.
"Changing how an entire community responds to cardiac arrest takes time, and our findings show just how challenging that can be," said study author Carolina Malta Hansen, M.D., Ph.D., a cardiologist and clinical research associate professor at Herlev and Gentofte Hospital and Copenhagen EMS in Denmark. She noted that a person's chance of survival while waiting for emergency medical services during a cardiac arrest decreases by 10% every minute without CPR.
Christopher Granger, M.D., FAHA, the trial's principal investigator and a cardiologist at Duke University, said the late increase in bystander CPR shows the program had some effect and suggests sustained outreach may be needed to improve survival.
The stakes are high. According to the American Heart Association's 2026 Heart Disease and Stroke Statistics, roughly 350,000 people in the U.S. experience out-of-hospital cardiac arrest each year, and only about 1 in 10 survive. Immediate CPR can double or triple survival odds, and the Association's 2025 Guideline for CPR and emergency cardiovascular care stresses rapid recognition, calling 9-1-1, starting CPR and using an automated external defibrillator when available. Yet only about 40% of out-of-hospital cardiac arrest victims receive bystander CPR and only 10% have an AED applied by a bystander before EMS arrives, per the Association's AED Fact Sheet.
The intervention combined free community CPR training in schools, workplaces and county government with an EMS component that trained 9-1-1 dispatchers to recognize cardiac arrest and coach callers through CPR, plus enhanced first-responder defibrillation. Community partners conducted 5,724 training events reaching 201,586 people, or 4.8% of residents in intervention counties, with participation ranging from more than 10% of residents in four counties to fewer than 3% in eight. Of 405 trial-provided defibrillators, 26 of 31 counties deployed the devices. Staffing shortages at 9-1-1 centers, the COVID-19 pandemic and Hurricane Helene created operational challenges.
Researchers said the trial established an efficient, high-quality network for continued work and pointed to the Association's Nation of Lifesavers initiative, which aims to double sudden cardiac arrest survival by 2030 and has raised U.S. bystander CPR confidence from 33% to 39% since 2023. Hansen emphasized that CPR education should be widely accessible and that strong first-responder programs matter most in rural areas where EMS response times may be longer.
