The purpose of this study was to assess the prescription of cardiovascular medications at time of discharge from the hospital following a myocardial infarction (MI) and to determine whether gender or ethnic differences existed in the prescription of these medications. Additionally, this study assessed whether the receipt of specific therapies differed appropriately by the presence or absence of selected comorbid conditions. Data for this study were drawn from the Corpus Christi Heart Project, a population-based surveillance program initiated in 1987 to study hospitalized cases of coronary heart disease (CHD) among women and men in the bi-ethnic population of Mexican Americans and non-Hispanic whites residing in Corpus Christi, Texas. Mexican American and white patients aged 25-74 years who had been recruited from 1988 to 1990 were included.

Mexican Americans were more likely to have diabetes than whites, and Mexican American women were less likely to smoke than white women. There were no ethnic differences in (congestive heart failure) CHF or hypertension. The adjusted odds ratio (Mexican Americans/whites) of receiving a greater number of medications was not significant (OR=0.62; 95% confidence interval=0.33-1.15). Significant effects were found for gender (men versus women), age (per 10 years), hypertension, cholesterol (per 20 mg/dl), and current cigarette smoking. The odds ratio (Mexican Americans/whites) of receiving specific medications was significantly greater than 1 for ACE inhibitors (OR=1.73), insulin (OR=1.81), oral hypoglycemics (OR=2.15), and was significantly less than 1 for antiarrhythmics (OR=0.39), angicoagulants (OR=0.42), and lipid-lowering drugs (OR=0.46). Significant gender differences were observed for diuretics, aspirin, digitalis, and insulin.

The authors then assessed three medication classes in detail. With regard to cholesterol lowering drugs, cholesterol level was the only factor that increased the odds of using these drugs, while ethnicity (Mexican American/whites) was the only factor that decreased the odds (OR=0.44). With regard to beta-blockers, hypertension was related to increased odds of using these drugs, while age and congestive heart failure decreased the odds. Ethnicity and gender were not associated with use of beta-blockers in adjusted analyses. Finally, with regard to angiotensin converting enzyme inhibitors, congestive heart failure, hypertension, and ethnicity (OR=1.59) increased the odds of using these drugs.

Although there was no consistent gender difference, there were substantial differences by race. The authors suggest "the overall pattern of less frequent receipt of medications among Mexican Americans may reflect ethnic differences in SES, physician perceptions that Mexican Americans may be less able to afford medications, are less compliant with medical recommendations, or other biases. It remains possible that this ethnic difference is appropriate and is related to differences in unmeasured aspects of severity and other comorbid conditions and other indications and contraindications to the use of specific types of medications."