(25) Epidemiology of Select Clinical Events of Interest Following a Myocardial Infarction

Publication Number: 699

Background: Adverse clinical events are associated with myocardial infarction (MI), but the rates of these events following MI and the time between an MI and these events reported in the literature are highly variable or unknown in certain populations.

Objectives: To determine the incidence rate of ischemic stroke, atrial fibrillation (AF), and heart failure (HF) within 90 days after an incident MI as well as the average duration of time for these events to occur after MI.

Methods: This was a descriptive, retrospective study using administrative medical and pharmacy claims data from a commercially insured U.S. population (IQVIA PharMetrics® Plus). This study included adults who experienced an MI between January 2016 and December 2020 and had at least one year of enrollment in the database prior to the MI. Individuals were followed starting on the day after their MI and up until 90 days after their MI for the occurrence of ischemic stroke, AF, and HF. Baseline patient characteristics were ascertained using all available data prior to the MI, including demographic variables, comorbidities, and select medication use. The incidence rates of each outcome following MI and the duration of days between MI and the outcomes were calculated in the overall cohort and within pre-defined subgroups.

Results: A total of 457,068 individuals had an MI during the study period and were eligible for inclusion in the study. Ischemic stroke after an MI occurred in 34,656 individuals, AF after an MI occurred in 18,917 individuals, and HF after an MI occurred in 27,544 individuals. Incidence rates of ischemic stroke, AF, and HF occurring within 90 days of MI were 355.4 (95% [Confidence Interval] CI: 351.7, 359.2), 233.1 (95% CI: 229.8, 236.4), and 409.7 (95% CI: 404.9, 414.6) per 1000 person-years, respectively. For all three outcomes, incidence rates were higher in subgroups of individuals who were aged ≥65 years, individuals with a history of peripheral artery disease, and individuals with a history of diabetes. Of those individuals who experienced an outcome of interest, it took on average 19, 21, and 20 days to experience stroke, AF, and HF following their MI, respectively.

Conclusions: This study highlights the demographics, comorbidities, medication use, and incidence of select clinical events occurring among a cohort of real-world patients in the acute phase after an MI. This study adds to the scientific evidence demonstrating the burden of clinical events experienced within a short period of time after an MI.