Objective: To investigate changes between 1987 and 1990 in the care and outcomes associated with acute myocardial infarction (AMI) in elderly patients.
Design: Retrospective cohort study using a longitudinal database created from Medicare administrative files.
Patients: Cohorts comprising a total of 856,847 AMI patients insured by Medicare between 1987 and 1990.
Main outcome measures: Annual rates of mortality at 30 days and 1 year following AMI, and the use of coronary angiography, coronary artery bypass graft surgery, and percutaneous transluminal coronary angioplasty during the first 90 days after a new AMI.
Results: Between 1987 and 1990, mortality rates decreased 10% overall from 26% to 23% at 30 days (P < .001) and from 40% to 36% at 1 year following AMI (P < .001). Declines in mortality and adjusted risks of 1-year mortality were similar in men and women and in blacks and whites, but mortality declines were more evident in those younger than 85 years. Meanwhile, the proportion of elderly AMI patients having angiography within the first 90 days after their index admission increased from 24% to 33% (P < .001); proportions increased for both genders and all races. The proportion of patients undergoing revascularization procedures increased from 13% to 21%; while rates of bypass surgery increased from 8% to 11%, rates of angioplasty doubled from 5% to 10% (all P < .001).
Conclusions: Between 1987 and 1990, survival of elderly patients following AMI improved significantly. While changes in patient treatment may be responsible, the increased use of thrombolytic therapy appears to be only a partial explanation. Also, while the use of coronary angiography and revascularization procedures increased dramatically, the degree to which it caused the improvement in survival could not be determined.