Breaking Point Toward Decreasing Prevalence of Myocardial Infarction Owing to Relative Stronger Decrease in Incidence Than Increase in Survival Rate (A Danish Cohort Study [1994–2016])

The aim of this study was to examine whether myocardial infarction (MI) incidence rate continues to decrease and to determine whether the relative magnitude of a potentially decreasing incidence rate has surpassed increasing survival, demasking a breaking point in trends of MI prevalence proportion. This was a nationwide population-based cohort study using medical registries covering all hospitals in Denmark (1994 to 2016). We identified 193,870 persons with a first-time hospitalization for MI. Age-standardized incidence rates (per 100,000 persons) decreased from 154 (95% confidence interval [CI] 149 to 159) in 1994 to 90 (95% CI 86 to 93) in 2016 for females, and from 335 (95% CI 326 to 344) in 1994 to 205 (95% CI 199 to 211) in 2016 for males. Age-standardized prevalence proportion increased overall from 1994 to 2004 with a subsequent plateau. From 2006 to 2016, age-standardized prevalence proportion decreased by 0.09% (95% CI 0.07% to 0.11%) for females (from 1.07% to 0.98%) and by 0.20% (95% CI 0.17% to 0.23%) for males (from 2.85% to 2.65%). The age-standardized prevalence proportion decreased solely among persons aged 55 to 84 years. It remained stable among persons aged <55 years and increased among persons aged ≥85 years until 2012 with subsequent stable trends. We conclude that the continuous decreasing age-standardized incidence rate of MI over decades has, although with increasing survival, led to an overall breaking point toward a decreasing age-standardized prevalence proportion of MI since 2006.