Objective: To compare observed, predicted, and risk-adjusted hospital mortality rates in white and African-American patients and to determine whether, as prior studies suggest, African-American patients would have higher predicted risks of death and similar or higher risk-adjusted mortality.
Design: Retrospective cohort study.
Setting: Thirty hospitals in northeast Ohio.
Patients: A total of 88205 eligible patients consecutively discharged in the years 1991 through 1993 with the following 6 diagnoses: acute myocardial infarction, congestive heart failure, obstructive airways disease, gastrointestinal hemorrhage, pneumonia, and stroke.
Methods: We measured predicted risks of death at admission for each diagnosis using validated multivariable models based on standard clinical data abstracted from patients' medical records. We then adjusted in-hospital mortality rates in white and African-American patients for predicted risk of death and other covariates using logistic regression analysis.
Main outcome measures: Predicted risk of death at admission and observed hospital mortality in white and African-American patients.
Results: Predicted risks of death were lower (P<.001) in African Americans for 4 of the 6 diagnoses. Adjusted odds of hospital death were lower (P<.01) in African Americans for 2 of the 6 diagnoses (congestive heart failure and obstructive airways disease) and similar for the other 4 diagnoses. For all diagnoses, in aggregate, the adjusted odds of hospital death were 13% lower in African-American compared with white patients (multivariable odds ratio, 0.87; 95% confidence interval, 0.80-0.94). Findings were similar if further adjustments were made for differences in length of stay, site of hospitalization, or discharge triage practices.
Conclusion: Contrary to our a priori hypotheses, predicted risks of death and risk-adjusted mortality rates were generally lower in African-American patients. Our finding of lower predicted risk may reflect racial differences in hospital admission practices or in access to outpatient care. However, our findings suggest that, once hospitalized, African-American patients attained similar or better outcomes, as measured by an important measure--hospital mortality.