The goal of this study was to examine the influence of patients’ race and age on the use of thrombolytic therapy, invasive cardiac procedures, and subsequent outcomes. Patients included in this study were selected retrospectively from those admitted to a metropolitan Veteran Affairs (VA) teaching hospital from October 1993 to September 1995 with a possible diagnosis of myocardial infarction. Included racial groups were Caucasian, African American, and Hispanic.

No racial differences were found for age, time to initial tests, length of hospitalization, or infarct location. Hispanics were more likely to have ST segment elevation (62% of Hispanics compared with 36% of Caucasians and 42% of African Americans) and less likely to have non-Q wave myocardial infarctions (54% of Hispanics compared with 70% of Caucasians and 69% of African Americans). There were no racial differences in the use of thrombolytic therapy, PTCA, CABG, or medications other than aspirin, but Caucasians were more likely to receive aspirin (95% versus 88% of African Americans and 85% of Hispanics) and African Americans were less likely to receive catheterization (51% versus 63% of Caucasians and 57% of Hispanics). There were various racial patterns for comorbidities. The in-hospital death rate was highest among Hispanics (21.6% versus 10.6% in Caucasians and 14.3% on African Americans), but the median mortality rate (22 months) was similar across racial groups. (The authors note that “the Hispanic population included older men with large infarctions and an increased incidence of cardiogenic shock, which accounts for the poor survival in this particular group.”)

Patients older than 65 years of age had a higher mortality rate, were less likely to be given thrombolytics or to undergo catheterization or angioplasty, were more likely to have lateral or nonlocalized non-Q wave infarctions, and had a higher comorbidity count.

Among patients with ST segment elevation, thrombolytic therapy was used less for Hispanics (30%) than African Americans (46%) and Caucasians (56%). The most common reason for not using this therapy was the patient having had greater than 12 hours of chest pain, but the next most frequent reasons differed by racial group: for Caucasians, missing ECG and cancer; for African Americans, stroke, hypertension and cancer; and for Hispanics, shock, primary PTCA and missing ECG.

Those who received catheterization were younger, less often African American, more often treated with thrombolytic agents, hospitalized longer, less likely to have heart failure, and more often discharged on aspirin, beta-blockers, and calcium channel blockers. Those who did not receive catheterization were more likely to be discharged on ACE inhibitors. In-hospital mortality, when selected for cardiac catheterization, was lower than for noninvasive therapy (4.8% versus 24.1%), and this survival benefit persisted long term (13.8% versus 43.2%).

Subsequent treatment plans (PTCA, CABG and medical therapy) also differed in several ways, most notably in that these patients were younger and had lower mortality rates. No racial patterns were noted.

Multivariate analyses that controlled for age, race, comorbidity count, thrombolytic use and heart failure found that those over 70 years of age and those with heart failure were less likely to be catheterized, but there were no significant race differences. A similar analysis indicated that increasing age, Hispanic (versus Caucasian) race, and higher comorbidity increased the odds of in-hospital death. Finally, among those with ST segment elevation, Hispanics were less likely than Caucasians to receive thrombolytic therapy.

The authors offer few explanations for these patterns. With regard to thrombolytic agent use, they could not draw conclusions about the benefits of thrombolytic treatment due to the small numbers of patients in each racial/age group. Hispanics tended to have more problematic comorbid diseases (including diabetes and CVD). But, “among Hispanics meeting ECG criteria for thrombolytic therapy, there was no survival benefit to treatment. Bypass grafting was chosen for a significant percentage of Hispanics, which reflects recent practice in the choice of revascularization procedure for diabetics. In contrast, those African Americans with ST segment elevation who were given thrombolytic agents had a low mortality. (However,) the database on comorbid disease may be incomplete and thus not accurately display potential explanation for increased mortality within a racial group.”

With regard to catheterization, the authors again do not draw firm conclusions. “Although some patients undoubtedly underwent catheterization and revascularization during a subsequent admission, it is unlikely that the lower rate of catheterization among African Americans would be completely offset by an excess of these procedures in the months after discharge. (However it is possible) that procedures were obtained outside of the VA medical center.”