Compared with white patients, black patients who have an in-hospital cardiac arrest are significantly less likely to survive to hospital discharge, having lower rates of successful resuscitation and postresuscitation survival, although much of this survival difference was associated with the hospital in which black patients received care, according to a study in the September 16 issue of JAMA.

"Survival following in-hospital cardiac arrest represents a unique opportunity to examine racial disparities in medical care and outcomes. In-hospital cardiac arrest is an emergency condition tightly linked to processes of care and for which there is little debate regarding clinical appropriateness of treatment in eligible patients," according to background information in the article. "Racial differences in survival have not been previously studied after in-hospital cardiac arrest, an event for which access to care is not likely to influence treatment."

Paul S. Chan, M.D., M.Sc., of Saint Luke's Mid America Heart Institute, Kansas City, Mo., and colleagues used data from the National Registry of Cardiopulmonary Resuscitation (NRCPR) to examine whether racial differences exist in survival for patients with in-hospital cardiac arrest. The study included 10,011 patients from 274 hospitals who underwent defibrillation for a cardiac arrest. The average age in the study population was 67 years, 6,021 were men (60.1 percent), and 1,883 were black (18.8 percent).

Several patient and hospital factors differed by race, including white cardiac arrest patients being older and more likely to be male; black patients were more likely to have ventricular fibrillation as their initial presenting arrest rhythm, were sicker at the time of cardiac arrest (higher rates of renal insufficiency, diabetes mellitus, central nervous system depression, acute stroke, pneumonia, sepsis, major trauma, and requirement for hemodialysis), and were more likely to be admitted to a hospital unit not monitored, to a hospital with greater than 500 beds, and in the southeastern United States.

The researchers found that black patients had a 27 percent lower overall rate, and a 12 percent lower absolute rate, of survival to hospital discharge, compared with white patients. "These unadjusted survival differences by race were, in large part, attributable to black patients being more likely to receive treatment at hospitals with worse outcomes."

These differences narrowed after adjusting for patient characteristics and for the hospital to which the patient was admitted. "However, further adjustment for hospital process variables did not meaningfully [diminish] residual differences, and black patients remained 10 percent less likely to survive to hospital discharge," the authors note.

"Lower rates of survival to discharge for blacks reflected lower rates of both successful resuscitation (55.8 percent vs. 67.4 percent for whites) and postresuscitation survival (45.2 percent vs. 55.5 percent for whites)," they write. "The racial difference in postresuscitation survival was eliminated after multivariable adjustment, and was largely explained by the hospital site at which patients received postresuscitation care."

"Collectively, these findings suggest that strategies to eliminate racial disparities in survival after in-hospital cardiac arrest are not likely to succeed unless they are accompanied by successful identification and implementation of interventions that improve resuscitation survival in those poorly performing hospitals in which black patients are more likely to receive care."