Elsevier

American Heart Journal

Volume 146, Issue 6, December 2003, Pages 1030-1037
American Heart Journal

Clinical investigations
Universal health insurance coverage does not eliminate inequities in access to cardiac procedures after acute myocardial infarction

https://doi.org/10.1016/S0002-8703(03)00448-4Get rights and content

Abstract

Background

It remains unclear whether socioeconomic status (SES) influences access to invasive cardiac procedures after acute myocardial infarction (AMI) in a universal health care system. The objective of this study was to evaluate the effect of SES on access to cardiac procedure after AMI in a universal health care system.

Methods

This was an observational cohort study of all patients with a first AMI in the province of Quebec, Canada, between 1985 to 1995. Information on treatment was obtained from the discharge and physicians' claims databases. SES was obtained from census data by linking postal codes. SES-independent predictors of use were identified, then incorporated in hierarchical models to predict use in low, medium, and high SES areas. The main outcome measures were rates of cardiac catheterization, percutaneous coronary intervention (PCI), and coronary artery bypass graft surgery (CABG) as a function of SES.

Results

SES data were available for 62,364 individuals with a first AMI. Of these, 65% were men and the mean age was 64 ± 13 years. Rates of cardiac procedures rose with an increase in several SES measures. After adjustment for individual-level predictors of use of cardiac catheterization, average rent, (odds ratio per $100 difference: 1.57, 95% credible interval: 1.36 to 1.80) and proportion of renters, (odds ratio, 2.2; 95% CI: 1.21 to 3.73) in the area were independent SES predictors. Patients in low SES areas (median family income: $ 30,809 CDN) were less likely to undergo cardiac catheterization than patients in high SES areas ($92,169 CDN) (men: 33%; compared with 47%; women: 18%; compared with 47%). However, among patients with cardiac catheterization, SES was not associated with the use of revascularization procedures. For example, PCI rates for men within 90 days after AMI were 26%, compared with 25% in low and high SES areas, respectively. CABG rates were 15%, compared with 19%.

Conclusions

We found that in the universal health care system of Canada, access to cardiac catheterization after AMI varied according to SES. Among those with cardiac catheterization, SES did not appear to influence further use of revascularization procedures.

Section snippets

Study population

We used the Quebec Discharge Summary database to identify all patients admitted with a diagnosis of a first AMI between January 1, 1985, to December 31, 1995. As previously described, patients were identified for inclusion in the AMI cohort if hospitalized for a main diagnosis of AMI (ICD9 code 410) for the first time as ascertained by the absence of a hospitalization for AMI for at least the previous 3 years.9 This database was linked to the physicians' claims database to obtain information on

Study population

Between January 1, 1985, and December 31, 1995, a total of 85,435 patients were admitted with a first AMI to an acute care hospital in the province of Quebec. These patients represent close to the totality of individuals with a first AMI in the province of Quebec. Twenty-seven percent of patients had missing or invalid postal codes or SES data were not available in the 1991 census. These patients were from low populated areas. These patients were excluded from the current analysis, leaving

Discussion

We found that in the universal health care system of Canada, access to cardiac catheterization post-AMI varied according to SES both in 1989 and 1994. After adjustment for the available individual-level predictors of use of cardiac catheterization, the variability was mostly explained by SES variables. As a result, the probability of cardiac catheterization for a patient living in a low SES area was considerably lower than that of a patient in a high SES area, independent of age, comorbidities,

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  • Cited by (75)

    • Socioeconomic Status, Mortality, and Access to Cardiac Services After Acute Myocardial Infarction in Canada: A Systematic Review and Meta-analysis

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    Dr Pilote is an Investigator of the Canadian Institutes of Health Research.

    Supported in part by the Fonds de la recherche en santé du Québec (grant 990726-104).

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