Ramsey DJ, Goff DC, Wear ML, Labarthe DR, Nichaman MZ.
Sex and ethnic differences in use of myocardial revascularization procedures in Mexican-Americans and non-Hispanic whites: the Corpus Christi Heart Project.
J Clin Epidemiol 1997;50(5):603-9.

This study is a valuable contribution to the literature on differences in cardiac care between Hispanic patients and white patients. The present report is part of the Corpus Christi Heart Project, a population-based surveillance program based in Nueces County, Texas for patients hospitalized for coronary heart disease. The population of this county is 43% non-Hispanic white and 52% of Hispanic origin (of these 92% are Mexican-American). For the purpose of this study, ethnicity was either self-reported or determined by information in the hospital records.

Study participants were residents of Nueces County, between the ages of 25 and 74 years, and were admitted with a definite or possible MI to any of the seven acute care hospitals or any of the three hospitals performing percutaneous transluminal coronary angioplasty (PTCA) or aortocoronary bypass surgery (ACBS) between May 1, 1988 and April 30, 1990. Data were collected and analyzed in three stages: (1) age-adjusted rates of use of PTCA and ACBS in the general population were computed by direct standardization to the 1990 Texas population; (2) rates of cardiac catheterization were examined among patients hospitalized for MI; and (3) rates of PTCA and ACBS were determined among patients who received catheterization during a hospitalization for MI. The first stage of analysis was conducted to identify potential subgroup differences that could be explained by differences in health status (need for the procedures) or barriers to access. In the second and third stages, a relatively homogenous group of patients, with extensive clinical data on disease status, was examined to evaluate the appropriateness of any observed gender or ethnic differences in the receipt of revascularization procedures.

In the analysis of cardiac catheterization after MI, ethnic differences were present. After potential confounders were controlled for, “Mexican-Americans received catheterization 18% less often than non-Hispanic whites (p=0.11).” These ethnic disparities were also present in the third stage of analysis. Non-Hispanic whites received PTCA (23 versus 13%, p< 0.01), but not ACBS, more frequently than Mexican-Americans. The differences persisted after adjustment for disease severity and other potential confounders: Mexican-Americans were 35% less likely to receive PTCA but not less likely to receive ACBS as compared to non-Hispanic whites.

A limitation of the study is that the investigators did not control for socio-economic status and medical insurance coverage, both of which are significant barriers to receipt of cardiac care. Since the Mexican-American population in the study area is “known to have lower per capita income and lower educational attainment than non-Hispanic whites,” the observed ethnic differences may be explained by class differences in the study population.