Sex Differences in Mortality After Myocardial Infarction: A German Nationwide Cohort Study.

BACKGROUND: Acute myocardial infarction (AMI) remains one of the leading causes of death in Germany, accounting for 41 258 deaths in 2024. The evidence on sex differences in mortality after AMI is mixed, especially for outcomes beyond the acute phase. We used data from a large nationwide database to study sex differences in 12-month mortality after AMI in Germany. METHODS: ). Adults who had a principal inpatient discharge diagnosis of incident AMI in 2023 were included in the analysis. The endpoint was all-cause mortality within 12 months. Cox models were fitted with sequential adjustment for age, infarction type, comorbidities, and prior cardiovascular medication. RESULTS: 62 884 women and 113 019 men were included in the analysis. The women were older and had more comorbidities. The crude 12-month mortality was higher in women than in men (21.0% vs 17.8%; 251 vs 207 per 1000 person-years). After adjustment for age, however, the reverse was true: mortality was lower in women than in men (hazard ratio [HR] 0.88; 95% CI 0.86-0.90). This remained the case in the fully adjusted model (HR 0.84; 95% confidence interval [CI] 0.82-0.85). In exploratory stratified analyses, men and women under age 60 did not differ in mortality, while in older age groups and after non-ST-segment elevation myocardial infarction (NSTEMI), mortality was lower in women (but not after ST-segment elevation myocardial infarction [STEMI]). CONCLUSION: Multivariable analysis revealed a slightly lower 12-month mortality among women after the diagnosis of an acute myocardial infarction. Because the adjustment included variables that may act as mediators on the causal pathway between sex and mortality, the adjusted estimates should be interpreted with caution.