Middle-Aged Women and Post-Myocardial Infarction Mortality: A Vulnerable Group? Real-World Evidence from a Brazilian Public Health System Cohort

Abstract

Background

Cardiovascular diseases are the leading cause of death in Brazil, with acute myocardial infarction (MI) accounting for a significant share of these fatalities. Women tend to experience MI at older ages and in the presence of more comorbidities — factors that may negatively impact prognosis. Locally generated evidence is essential to guide targeted strategies within the public health care system.

Objective

To assess the influence of age and sex on post-MI mortality among patients treated within the Brazilian Unified Health System.

Methods

This retrospective cohort study included patients residing in Curitiba who were hospitalized for MI (International Classification of Diseases, 10th Revision code I21) between 2008 and 2015. Mortality data were obtained from the Brazilian Mortality Information System. In-hospital mortality, as well as mortality at 6 and 12 months and at the end of follow-up, were analyzed. Age (both as a continuous and categorical variable) and sex, as well as their interaction, were included in the analysis. Statistical significance was set at 5% (p < 0.05).

Results

The sample included 4,896 patients (mean age 62 ± 12.4 years; 34.1% women), with an average follow-up of 50.9 months. Overall mortality was 29.5%. On average, women experienced MI 5 years later than men (65.1 vs. 60.3 years; p < 0.001) and had higher follow-up mortality (p < 0.001). However, in the multivariate analysis, only age remained significantly associated with mortality. Age-stratified analysis revealed a higher risk of death among women aged 45-54.9 years (p = 0.004).

Conclusion

Older age contributes to the worse post-MI prognosis observed among women compared to men. However, women in early middle age showed an increased risk of death, representing a potentially vulnerable group requiring specific attention.