title: Comparison of Long-Term Mortality of Patients Aged ≤40 Versus >40 Years With Acute Myocardial Infarction.
abstract: Young patients with acute myocardial infarction (MI) have a more favorable prognosis than older patients with MI. However, there are limited data comparing the prognosis of young patients with MI with young population controls. Comparison with an age-matched background population could unmask residual mortality risk in young patients with MI 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 to 2005, of which 601 patients were ≤40 years (young MI). The relative survival ratio (RSR) was calculated as the ratio of the observed survival of patients with MI divided by the expected survival, estimated from the background population (n = 3,771,700) matched for age, gender, and follow-up year. An RSR of <1.0 or >1.0 indicates poorer or better survival, respectively, than the background population. The 12-year all-cause and cardiovascular mortality of young versus older patients was 12.8% versus 50.7% (p <0.001) and 9.2% versus 34.5% (p <0.001), respectively. The adjusted hazard ratio (95% confidence interval) for all-cause and cardiovascular mortality comparing young with older patients was 0.20 (0.16 to 0.27) and 0.27 (0.20 to 0.36), respectively. The RSR (95% confidence interval) of young and older patients was, respectively, 0.969 (0.950 to 0.980) and 0.804 (0.797 to 0.811) at 1 year, 0.942 (0.918 to 0.960) and 0.716 (0.707 to 0.726) at 5 years, and 0.908 (0.878 to 0.938) and 0.638 (0.620 to 0.654) at 9 years. In conclusion, despite a fivefold lower long-term mortality than older patients with MI, young patients with MI remain at significantly greater risk of long-term mortality than an age-matched background population.
authors.affiliation: National University Heart Centre, National University of Singapore, Singapore, Singapore.
authors.forename: Mingxue
authors.initials: M
authors.lastname: Jing
authors.affiliation: Department of Cardiology, National Heart Centre, Singapore, Singapore; Center for Quantitative Medicine, Duke-NUS Graduate Medical School, Singapore, Singapore.
authors.forename: Fei
authors.initials: F
authors.lastname: Gao
authors.affiliation: Department of Cardiology, National Heart Centre, Singapore, Singapore.
authors.forename: Qifeng
authors.initials: Q
authors.lastname: Chen
authors.affiliation: National University Heart Centre, National University of Singapore, Singapore, Singapore.
authors.forename: Leonardo P
authors.initials: LP
authors.lastname: de Carvalho
authors.affiliation: Department of Cardiology, National Heart Centre, Singapore, Singapore.
authors.forename: Ling-Ling
authors.initials: LL
authors.lastname: Sim
authors.affiliation: Department of Cardiology, National Heart Centre, Singapore, Singapore.
authors.forename: Tian-Hai
authors.initials: TH
authors.lastname: Koh
authors.affiliation: Department of Cardiology, Tan Tock Seng Hospital, Singapore, Singapore.
authors.forename: David
authors.initials: D
authors.lastname: Foo
authors.affiliation: Department of Cardiology, Khoo Teck Puat Hospital, Singapore, Singapore.
authors.forename: Hean-Yee
authors.initials: HY
authors.lastname: Ong
authors.affiliation: Department of Cardiology, Changi General Hospital, Singapore, Singapore.
authors.forename: Khim-Leng
authors.initials: KL
authors.lastname: Tong
authors.affiliation: National University Heart Centre, National University of Singapore, Singapore, Singapore.
authors.forename: Huay-Cheem
authors.initials: HC
authors.lastname: Tan
authors.affiliation: National University Heart Centre, National University of Singapore, Singapore, Singapore.
authors.forename: Tiong-Cheng
authors.initials: TC
authors.lastname: Yeo
authors.affiliation: Duke Clinical Research Institute, Durham, North Carolina.
authors.forename: Matthew T
authors.initials: MT
authors.lastname: Roe
authors.affiliation: Department of Cardiology, National Heart Centre, Singapore, Singapore.
authors.forename: Terrance
authors.initials: T
authors.lastname: Chua
authors.affiliation: National University Heart Centre, National University of Singapore, Singapore, Singapore. Electronic address: mark_chan@nuhs.edu.sg.
authors.forename: Mark Y
authors.initials: MY
authors.lastname: Chan
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D002318:Cardiovascular Diseases / Q000401:mortality*; D002423:Cause of Death; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009026:Mortality; D009203:Myocardial Infarction / Q000453:epidemiology*; D011379:Prognosis; D016016:Proportional Hazards Models; D012042:Registries; D012846:Singapore; D015996:Survival Rate