Comparison of Long-term Mortality of Patients Aged ≤ 40 Years versus > 40 Years with Acute Myocardial Infarction

Abstract Young patients with acute myocardial infarction (MI) have a more favourable prognosis than older patients with MI. However, there are limited data comparing the prognosis of young MI patients with young population controls. Comparison with an age-matched background population could unmask residual mortality risk in young MI patients that would otherwise not be apparent when merely comparing the mortality risk of young and older patients with MI. We studied 15,151 patients with AMI from 2000-2005, of which 601 patients were ≤40 years of age (young MI). The relative survival ratio (RSR) was calculated as the ratio of the observed survival of MI patients divided by the expected survival, estimated from the background population (n=3,771,700) matched for age, sex and follow-up year. A RSR of 1.0 indicates poorer or better survival, respectively, than the background population. The 12-year all-cause and cardiovascular mortality of young vs. older patients was 12.8% vs 50.7% (P