Process of Care and Outcome after Acute Myocardial Infarction for Patients with Mental Illness in the VA Health Care System: Are There Disparities?

Objective. To compare process of care and outcome after acute myocardial infarction, for patients with and without mental illness, cared for in the Veterans Health Administration (VA) health care system.

Data Sources/Setting. Primary clinical data from 81 VA hospitals.

Study Design. This was a retrospective cohort study of 4,340 veterans discharged with clinically confirmed acute myocardial infarction. Of these, 859 (19.8 percent) met the definition of mental illness. Measures were age-adjusted in-hospital and 90-day cardiac procedure use; age-adjusted relative risks (RR) of use of thrombolytic therapy, beta-blockers, angiotensin converting enzyme (ACE) inhibitors, or aspirin at discharge; risk-adjusted 30-day and one-year mortality.

Results. Patients with mental illness were marginally less likely than those without mental illness to undergo in-hospital angiography (age-adjusted RR 0.90 [95 percent confidence interval: 0.83, 0.98]), but there was no significant difference in the age-adjusted RR of coronary artery bypass graft surgery in the 90 days after admission (0.85 [0.69,1.05]), or in the receipt of medications of known benefit. For example, ideal candidates with and without mental illness were equally likely to receive beta-blockers at the time of discharge (age-adjusted RR 0.92 [0.82, 1.02]). The risk-adjusted odds ratio (OR) for death in patients with mental illness versus those without mental illness within 30 days was 1.00 (0.75,1.32), and for death within one year was 1.25 (1.00,1.53).

Conclusions. Veterans Health Administration patients with mental illness were marginally less likely than those without mental illness to receive diagnostic angiography, and no less likely to receive revascularization or medications of known benefit after acute myocardial infarction. Mortality at one year may have been higher, although this finding did not reach statistical significance. These findings are consistent with other studies showing reduced health care disparities in the VA for other vulnerable groups, and suggest that an integrated health care system with few financial barriers to health care access may attenuate some health care disparities. Further work should address how health care organizational features might narrow disparities in health care for vulnerable groups.