Long-Term Mortality of Older Patients With Acute Myocardial Infarction Treated in US Clinical Practice

Background: There is limited information about the long-term survival of older patients after myocardial infarction (MI).

Methods And Results: CRUSADE (Can rapid risk stratification of unstable angina patients suppress adverse outcomes with early implementation of the ACC/AHA guidelines) was a registry of MI patients treated at 568 US hospitals from 2001 to 2006. We linked MI patients aged ≥65 years in CRUSADE to their Medicare data to ascertain long-term mortality (defined as 8 years post index event). Long-term unadjusted Kaplan-Meier mortality curves were examined among patients stratified by revascularization status. A landmark analysis conditioned on surviving the first year post-MI was conducted. We used multivariable Cox regression to compare mortality risks between ST-segment-elevation myocardial infarction and non-ST-segment-elevation myocardial infarction patients. Among 22 295 MI patients ≥ age 65 years (median age 77 years), we observed high rates of evidence-based medication use at discharge: aspirin 95%, β-blockers 94%, and statins 81%. Despite this, mortality rates were high: 24% at 1 year, 51% at 5 years, and 65% at 8 years. Eight-year mortality remained high among patients who underwent percutaneous coronary intervention (49%), coronary artery bypass graft (46%), and among patients who survived the first year post-MI (59%). Median survival was 4.8 years (25th, 75th percentiles 1.1, 8.5); among patients aged 65-74 years it was 8.2 years (3.3, 8.9) while for patients aged ≥75 years it was 3.1 years (0.6, 7.6). Eight-year mortality was lower among ST-segment-elevation myocardial infarction than non-ST-segment-elevation myocardial infarction patients (53% versus 67%); this difference was not significant after adjustment (hazard ratio 0.94, 95% confidence interval, 0.88-1.00).

Conclusions: Long-term mortality remains high among patients with MI in routine clinical practice, even among revascularized patients and those who survived the first year.