Mortality in Norwegian men and women with an incident myocardial infarction

In general, mortality is higher in men than in women. However, it is unsettled whether this is the case after myocardial infarction. Some studies have shown higher mortality in men,1,2 whereas other have shown higher mortality in women, especially at younger ages.3–5 We studied mortality according to age in men and women with an incident myocardial infarction (MI). The Norwegian Cardiovascular Disease Registry (NCDR) is a national health registry that was established in 2012. We used episodes registered with MI in 2016–2018 and with no MI registered in the three previous years. MI was defined as ICD-10 codes I21 or I22 as main We calculated person-years from date of MI episode to date of death or 28. February 2020, whichever came first. We estimated mortality in age-groups 0–49, 50–54, 55–59, 60–64, 65–69, 70–74, 75–79, 80–84, 85–89, ≥90. We used these age-groups as a factor variable in Cox proportional hazard analyses. Percutaneous coronary intervention (PCI, 1 = yes, 0 = no) and number of contributory diagnoses (0, 1, 2,…,5, 6, 7+) registered in NCDR were additional independent factor variables in these analyses. The percentage with PCI was 44 and 33 in men and women below 75 years, and 25 and 17 in men and women 75 or older. The average of contributory diagnoses was 1.6, and 1.5 below 75 and 2.4 and 2.3 in men and women 75 years or older.