Long-term cardiovascular risk and costs for myocardial infarction survivors in a US commercially insured population
Objective To quantify clinical and cost long-term outcomes in cardiovascular stable post-myocardial-infarction patients.
Research design and methods Subjects with a history of myocardial infarction (MI) who were 50–64 years old and MI- and stroke-free for ≥12 months (index date) were identified in a large US claims database. Individuals were followed for up to 5 years (mean: 2.0 years) after their index date.
Main outcome measures Rates of MI, stroke, all-cause death, and a composite of these were analyzed via Cox regression models, adjusted for covariates. Results are reported for the overall population and the subgroups of those with type 2 diabetes, additional prior MI, and non-end-stage renal disease. As a secondary endpoint healthcare costs were evaluated at baseline and during each year of follow-up.
Results Over the follow-up period, which averaged 2 years, 7.6% of all 13,492 subjects (10.5% vs. 5.4% with and without the selected risk factors, respectively) experienced at least one of the outcome events. The cumulative incidence rates over the entire follow-up period for the primary composite outcome were 20.8% and 12.2% for those with and without the selected atherothrombotic risk factors, respectively. The cardiovascular-related per-person-per-year healthcare costs during follow-up were higher in those with ≥1 additional risk factor compared to those without: $15,247 versus $7521. Costs were elevated over baseline costs throughout follow-up.
Limitations Administrative claims data lack clinical detail. Generalizability of results is limited to the US commercially insured population of a similar age to that included in this study.
Conclusions High risk MI survivors who have been event free for ≥1 year remained at substantial risk of CV events and had increased healthcare costs for up to 5 years post-MI. These long-term risks have not been previously demonstrated in a working-age US population and suggest an unmet need for continuing secondary prevention long-term post-MI.
