Black patients less likely to survive cardiac arrests in hospitals

University of Michigan Health SystemSep 16 2009

Racial differences in care reflect hospital quality, resources

Black patients have lower rates of successful resuscitation and are less likely to survive an in-hospital cardiac arrest compared to white patients, according to a study in the Sept. 16 issue of the Journal of the American Medical Association.

In the study, black patients had a 12 percent lower overall rate of surviving the cardiac emergency in which the heart stops beating. Much of the racial difference was associated with the poor-performing hospitals where black patients received their care.

"Potential racial differences in access to care or preferences have been used to explain disparities in treatments and patient outcomes. But these are not likely to influence treatment in cardiac arrests since patients were already in the hospital and care of these patients is pretty clear," says lead author Paul S. Chan, M.D., MSc., cardiologist at St. Luke's Mid-America Heart Institute.

"The differences in survival by race actually appeared to have more to do with the hospitals than the patients themselves," Chan says.

Cardiologists from St. Luke's and the University of Michigan Health System along with their colleagues from the University of Washington, Yale University and Duke University evaluated the care leading up to and after 10,011 patients underwent defibrillation at hospitals across the United States.

While black patients tended to be sicker when admitted, they were more likely to stay in a hospital unit that was not monitored, and in a hospital with worse patient outcomes for these types of emergencies.

Lower survival rates for black patients reflected lower rates of successful resuscitation and lower rates of survival to discharge even after a successful resuscitation.

Just over half of black patients were successfully revived after an in-hospital cardiac arrest, compared to 67.5 percent of white patients. The racial difference in lower post resuscitation survival - 45.2 percent vs. 55.5 percent for white patients - was largely explained by the quality of the hospital.

"The link between the quality of the hospital and lower rates of post resuscitation survival is particularly striking," says senior author Brahmajee K. Nallamothu, M.D., MPH, cardiologist at the U-M Cardiovascular Center. "It suggests that there are important facility-level characteristics at the hospitals where black patients are most commonly treated."

Those differences may include less experienced staff in intensive care units or infrequent use of aggressive therapies like cardiac catheterization or hypothermia, Nallamothu explains.

Authors say reducing the death rate among black cardiac patients may need a new focus.

"These findings suggest that strategies to eliminate racial disparities in survival after in-hospital cardiac arrest are not likely to be successful unless they are accompanied by - interventions that improve resuscitation survival in those poorly performing hospitals in which black patients are more likely to receive care," authors write.

The data on racial differences in care was gleaned from a national registry of in-hospital resuscitation events gathered by the American Heart Association's National Registry of Cardiopulmonary Resuscitation, a registry the U-M Medical Center participates in for quality improvement.