(Reuters Health) - Neighborhoods with higher proportions of black residents might benefit from programs that teach people how to help others with cardiac arrest, U.S. researchers say.

People whose heart stopped in predominately black neighborhoods were less likely to receive cardiopulmonary resuscitation (CPR) and get a shock to restart their heart than people who suffered cardiac arrest in mostly white areas, the researchers found.

Survival after cardiac arrest was also worse in predominantly black neighborhoods than in white neighborhoods.

“We really need to focus on novel implementation efforts to address this,” said lead author Dr. Monique Anderson Starks, of the Duke Clinical Research Institute in Durham, North Carolina.

More than 350,000 people in the U.S. went into cardiac arrest outside of a hospital setting in 2016, according to the American Heart Association (AHA). About 46 percent received CPR and about 12 percent survived.

Starks emphasized that cardiac arrest shouldn’t be confused with a heart attack, in which the heart keeps beating.

“Cardiac arrest is far more sinister and dangerous,” she told Reuters Health. “It’s characterized by complete cessation due to an arrhythmia. The heart just stops.”

As reported in JAMA Cardiology, she and her colleagues analyzed data on 22,816 adults who went into cardiac arrest outside a hospital setting from 2008 through 2011. The arrests were not related to injuries.

About 40 percent received CPR from a bystander and about 4 percent got a shock from an automatic external defibrillator (AED) before emergency responders arrived at the scene.

As the proportion of black residents in a neighborhood increased, the proportion of people in cardiac arrest who received CPR or a shock from an AED decreased.

About 43 percent of people in cardiac arrest received CPR in neighborhoods where less than 25 percent of residents were black, compared to about 18 percent in neighborhoods where more than 75 percent of residents were black, for example.

Similarly, about 4.5 percent of people in cardiac arrest received a shock from an AED in neighborhoods with the fewest black residents, compared to about 1 percent in areas with the most black residents.

Overall, about 11 percent of patients survived long enough to be discharged from the hospital. That rate was about 12 percent in neighborhoods with the fewest black residents, compared to about 6 percent in neighborhoods with the most black residents.

Survival odds were the same regardless of whether patient was white or black.

“We can assume that lower bystander CPR rates are playing a role here, but also acknowledge that other factors we aren’t aware of are contributing to this disparity,” said Starks.

Researchers also found that emergency responders arrived at the scene faster in predominantly black neighborhoods and spent more time trying to resuscitate people, but it also took longer for them to use a defibrillator in those areas.

“This well-designed study highlights the inability of the U.S. health care system to provide equitable care for patients regardless of their race/ethnicity or socioeconomic status,” write Dr. Raina Merchant and Dr. Peter Groeneveld, of the University of Pennsylvania’s Perelman School of Medicine in Philadelphia, in an accompanying editorial.

“Too little focus has been placed on reducing barriers to access across diverse communities,” they say, adding that research now must “move beyond describing disparities for vulnerable populations and instead focus on implementing practices that reduce and/or eliminate disparities.

SOURCE: bit.ly/2woPqbS and bit.ly/2wpgZli JAMA Cardiology, online August 30, 3017.