Incidence and outcome of first myocardial infarction according to gender and age in Denmark over a 35-year period (1978-2012)

Abstract

Aims: To examine temporal changes in incidence and 1-year mortality of first myocardial infarction (MI) in different age groups for both genders in Denmark over a 35-year period (1978-2012).

Methods and results: Patients aged 30 years or older admitted with first MI in Denmark from 1978 to 2012 were included (n = 316 790). Overall, first MI incidence per 100 000 person-years (/105 p.y.) decreased significantly from 500 to 297/105 p.y. for males and from 229 to 156/105 p.y. for females. The decline was greatest among men aged 70-79 from 1460 to 643/105 p.y. (-56%). The majority of age groups also experienced declining incidence. However, men aged 30-39 and ≥90 years as well as females aged 30-49 and ≥90 years had increasing incidence during the study period. Moreover, the incidence decreased from 1978 to 1996 among males aged 40-49 and females aged 50-59 years, but increased in the remainder of the study period. One-year case-fatality declined significantly from 50 to 9% of MI male patients, and from 53 to 15% of MI female patients when comparing 1978 to 2012. Statistical analysis with Poisson models demonstrated that the mortality rate increased with age and decreased with time and indicated no significant difference between genders.

Conclusions: During the period from 1978 to 2012, there was a significant decline in MI incidence among most age groups for both genders; however, an incidence increase was observed in men under 50 and women under 60 years, and ≥90 years for both genders. One-year case-fatality decreased constantly during the study period.