The objective of this study was to explain race/ethnic disparities in hospitalizations, utilization of high-technology diagnostic and revascularization services, and mortality of elderly ischemic heart disease (IHD) patients.
A longitudinal Medicare claims database of all Part A hospital and Part B physician services provided elderly patients admitted for IHD in 1997 is used to construct admission, utilization, and mortality rates for whites and blacks, Asians, Hispanics, and American Indians. Z-scores are used to test differences in rates between whites and minorities at the 99% confidence level. Logistic and proportional hazard models are used to predict the likelihood of revascularization and its effects on race/ethnic survival 2 years postdischarge.
The setting of this study was an acute hospital supplemented by all ambulatory Part B outpatient providers of care.
Participants included all 700,000 age 65+ Medicare beneficiaries in fee-for-service identified with IHD as a primary diagnosis on admission in 1997.
Measurements and Main Results:
Whites were 26% more likely to be admitted for IHD than blacks, 50% more likely than Asians, 5% more than American Indians, but 3% less likely than Hispanics. Once admitted, elderly blacks and American Indians undergo invasive diagnostic and surgical revascularization far less often than whites (P < 0.01), although blacks are equally as likely as whites to be admitted to an open heart hospital. Controlling for other factors, whites reduce their 2-year mortality by 20% by undergoing revascularization 41% of the time. Blacks gain only 11% as a result of much lower rates and gains to revascularization than whites. Asians and Hispanics were slightly more likely than whites to undergo revascularization but gain less than whites from the procedure.
Despite having similar Medicare health insurance coverage, elderly utilization and IHD mortality rates differ markedly not only between whites and minorities, but within minority groups themselves. A large, nationally representative survey of physicians and patients is needed to distinguish between systemwide “failures to refer” and patient “aversions to surgery” as explanations for lower black rates of surgical interventions.