The effect of dementia on outcomes and process of care for Medicare beneficiaries admitted with acute myocardial infarction.

OBJECTIVES

To determine differences in mortality after admission for acute myocardial infarction (AMI) and in use of noninvasive and invasive treatments for AMI between patients with and without dementia.

DESIGN

Retrospective chart review.

SETTING

Cooperative Cardiovascular Project.

PATIENTS

Medicare patients admitted for AMI (N=129,092) in 1994 and 1995.

MEASUREMENTS

Dementia noted on medical chart as history of dementia, Alzheimer's disease, chronic confusion, or senility. Outcome measures included mortality at 30 days and 1-year postadmission; use of aspirin, beta-blocker, angiotensin-converting enzyme (ACE) inhibitor, thrombolytic therapy, cardiac catheterization, coronary angioplasty, and cardiac bypass surgery compared by dementia status.

RESULTS

Dementia was associated with higher mortality at 30 days (relative risk (RR)=1.16, 95% confidence interval (CI)=1.09-1.22) and at 1-year postadmission (RR=1.18, 95% CI=1.13-1.23). There were few to no differences in the use of aspirin and beta-blockers between patients with and without a history of dementia. Patients with a history of dementia were less likely to receive ACE inhibitors during the stay (RR=0.89, 95% CI=0.86-0.93) or at discharge (RR=0.90, 95% CI=0.86-0.95), thrombolytic therapy (RR=0.82, 95% CI=0.74-0.90), catheterization (RR=0.51, 95% CI=0.47-0.55), coronary angioplasty (RR=0.58, 95% CI=0.51-0.66), and cardiac bypass surgery (RR=0.41, 95% CI=0.33-0.50) than patients without a history of dementia.

CONCLUSION

The results imply that the presence of dementia had a major effect on mortality and care patterns for this condition.