Abstract Body (Do not enter title and authors here):
Introduction: ST-segment elevation myocardial infarction (STEMI) requires urgent intervention, yet significant disparities in outcomes persist. While sex and racial/ethnic disparities in STEMI mortality are documented, and socioeconomic status (SES) is a known predictor, the independent impact of sex, race/ethnicity, and SES on key in-hospital outcomes (mortality, length of stay [LOS], total charges) within a large, contemporary national cohort remains incompletely characterized.

Methods: We analyzed the National Inpatient Sample (NIS)(2018-2022) for adults with STEMI. Van Walraven Weighted Elixhauser Comorbidity index was used to survey linear and logistic regression models with 38 covariates to assess associations between sex, race (White [reference], Black, Hispanic, Asian), national income quartiles (lowest quartile [reference]), and in-hospital outcomes: mortality, length of stay (LOS), and total charges.

Results: Among 1,013,435 adults with STEMI, significant disparities emerged. Females (OR:1.24; 95%CI:1.20-1.29; p<0.001), Black (OR:1.10; 95%CI:1.04-1.17; p=0.01), Hispanic (OR:1.15; 95%CI:1.08-1.22; p<0.001), and Asian patients (OR:1.10; 95%CI:1.002-1.2001; p=0.04) showed higher mortality odds versus males and Whites, respectively. Higher income quartiles had lower mortality odds: second lowest quartile (OR:0.90; 95%CI:0.86-0.95; p<0.001), second highest (OR:0.83; 95%CI:0.78-0.87; p<0.001), highest quartile (OR:0.77; 95%CI:0.73-0.81; p<0.001). Females had shorter LOS (β:-0.09 days; 95%CI:-0.16 to -0.03; p<0.001), while Black (β:0.32 days; 95%CI:0.19-0.45; p<0.001) and Hispanic patients (β:0.37 days; 95%CI:0.26-0.50; p<0.001) had longer LOS. Total charges were lower for females (β:-$11,326; 95%CI:-$13,161 to -$9,490; p<0.001) and Black patients (β:-$4,623; 95%CI:-$8,357 to -$889; p=0.01), but higher for Hispanics (β:$25,796; 95%CI:$21,177-$30,417; p<0.001) and Asians (β:$8,711; 95%CI:$2,047-$15,377; p=0.01). Income quartiles did not predict LOS or charges (all p>0.05).

Conclusion: Significant sex, racial, and income-based disparities persist in STEMI mortality, hospitalization duration, and costs, underscoring urgent needs for equity-focused interventions.