Sex Differences in Mortality after Myocardial Infarction: A Retrospective Cohort Study

BACKGROUND: We aimed to examine sex differences in mortality after myocardial infarction. METHODS: This retrospective cohort study included all first admitted patients 50 years or older with acute myocardial infarction hospitalized in Rajaei hospital of Karaj city, Iran, between 23 th March 2013 and 1 th January 2020. Data was retrieved from the hospital information system (HIS) database, including patient’s demographic and socioeconomic characteristics, medical history, acute myocardial infarction (AMI) type, treatment and procedures, and outcome of hospitalization. Simple and multivariate cox regression models were used to assess the association of gender with in-hospital mortality after AMI. Results were presented as crude and adjusted hazard ratios along with their 95% confidence interval (HR (95% CI).RESULTS: Results from the multivariable Cox regression analysis revealed that females had a higher risk of death than males after ST segment Elevation MI (STEMI) (adjusted HR (95% CI): 1.64 (1.15 – 2.36), P=0.007). However, in subgroup analysis by age groups, this significant increased risk was observed only in female patients aged 50 to 64 years than their male counterparts. There was no significant differences between males and females after non-STEMI and unspecified MI.CONCLUSIONS: Based on our findings, women aged 50 to 64 years may be more likely to die during hospitalization after STEMI than men.