Breaking Point Toward Decreasing Prevalence of Myocardial Infarction Owing to Relative Stronger Decrease in Incidence...

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.