Abstract Body (Do not enter title and authors here): Background: Previous studies have highlighted the impact of sex differences on the outcomes of patients admitted for ST-elevation myocardial infarction (STEMI). However, there is limited evidence as to whether there is a difference in the outcomes between females and male STEMI patients who have a concomitant diagnosis of chronic kidney disease (CKD) and end-stage renal disease (ESRD).

Research Question: Does sex affect the outcomes for STEMI patients with concomitant CKD and ESRD?

Methods: This is a retrospective population-based cohort study that uses the National Inpatient Sample database. CKD patients in the United States hospitalized for STEMI were identified using the International Classification of Diseases, Ninth and Tenth Revision (ICD-9 and 10) codes. Inclusion criteria were adult patients who were hospitalized from 2012 to 2020. A subset of patients with ESRD were also identified. Multivariate regression analysis was performed, with the model adjusted for age and comorbidities. The primary outcome of interest was in-hospital mortality. Secondary outcomes evaluated included ischemic stroke, major bleeding complications, pressor requirement, permanent pacemaker implantation, percutaneous coronary intervention, coronary artery bypass grafting, surgery, pericardiocentesis, mechanical circulatory support, and mechanical ventilation.

Results: A total of 1,283,255 STEMI patients without CKD, 158,715 STEMI patients with CKD, and 22,690 STEMI patients with ESRD were identified and analyzed. Among patients with STEMI and CKD, females demonstrated higher in-hospital mortality compared to male counterparts (16.7% vs 12.7%, aOR=1.13, 95% CI: 1.05-1.21, p<0.01). Females were also more likely to develop ischemic stroke (4.0% vs 3.0%, aOR=1.16, 95% CI: 1.01-1.34, p=0.04). While there was no sex difference in the in-hospital mortality and most secondary outcomes among STEMI patients with ESRD, female patients in this group were less likely to receive coronary artery bypass grafting (5.0% vs 8.7%, aOR=0.54, 95% CI: 0.42-0.70, p<0.001) and mechanical circulatory support (12.8% vs 17.8%, aOR=0.69, 95% CI: 0.58-0.83, p<0.001).

Conclusion: Increased in-hospital mortality rates were shown for females admitted for STEMI with CKD. However, for STEMI patients with ESRD, there was no significant difference between males and females with respect to mortality rates. Further research needs to be conducted to better explain this said difference in outcomes.