Blacks Fare Worse After Cardiac Arrest
TUESDAY Sept. 15, 2009 -- Black patients who suffer cardiac arrest in the hospital are much less likely to survive than white patients, a new study finds.
Most of this disparity appears to result from the hospital in which black patients receive care, although other factors play a role as well, the researchers said.
"We know that survival after having a cardiac arrest in the hospital setting has always been historically low," said lead researcher Dr. Paul S. Chan, a cardiologist at St. Luke's Mid-America Heart Institute in Kansas City. "The rate of survival has been about 30 to 33 percent on average."
But the survival rates for blacks were significantly lower, 25 percent vs. 37 percent for whites, Chan said.
"This 12 percent absolute difference in survival is larger than any survival I can think of in terms of a racial disparity, in any other medical condition," he said.
The report is published in the Sept. 16 issue of the Journal of the American Medical Association.
For the study, Chan and colleagues used data from the National Registry of Cardiopulmonary Resuscitation to look at differences in survival among patients with in-hospital cardiac arrest.
They collected information on 10,011 patients, about 19 percent of whom were black, from 274 hospitals. These patients had all been defibrillated after a cardiac arrest.
The lower rates of survival to hospital discharge for blacks reflected lower rates of successful resuscitation (55.8 percent for blacks vs. 67.4 percent for whites) and survival after resuscitation (45.2 percent for blacks vs. 55.5 percent for whites), the researchers noted.
About a third of the difference can be explained by the patients themselves, Chan said, "Black patients were sicker when they had a cardiac arrest than white patients," he said.
Another third of the difference was explained by the hospitals many black patients were in, Chan said.
"This suggests that black patients were having cardiac arrests in hospitals that, on average, did a lot worse, in terms of survival, for all their patients, compared with white patients who went to hospitals that performed better, and patients were more likely to live in those hospitals," he said.
In addition, the quality of care after resuscitating a patient was worse in hospitals treating mostly black patients compared with care in hospitals treating white patients, Chan said.
"The hospital effect is huge and substantial, and is a contributor to the difference between black and white survival," he said. "If we can improve survival in those lower-performing hospitals at which black patients are more likely to be having cardiac arrest, we can eventually narrow the difference between black and white survival."
The remaining difference in survival between blacks and whites could not be explained, Chan said.
There did not seem to be a difference between the treatment blacks and whites received, so racism did not seem to play a role in care between blacks and whites, he said.
"We cannot exclude it fully," Chan said. "But it's really hard to imagine that a physician would treat a black patient differently than a white patient during a cardiac arrest."
Dr. Kim A. Williams, director of nuclear cardiology at the University of Chicago, was surprised that the disparity between blacks and whites wasn't greater.
"I am truly shocked at the results -- only 11 percent less initial resuscitation success," Williams said. "I thought the differential was far greater than this study demonstrates, but I am not surprised that the results are being attributed, at least in part, to the facilities involved rather than just the co-morbidities of the patients.
"Any attempts to improve this egregious disparity must start with the underlying risks and disease differences identified in this study, which would involve pre-morbid education, prevention and screening, and once risks are identified, better access to affordable chronic care and medications," he said. "It's clearly a system problem."
Posted: September 2009