Abstract Body (Do not enter title and authors here): Background:
Substance use disorder (SUD) is increasingly prevalent among young adults, often leading to severe cardiovascular complications. The specific impact of acute coronary syndrome (ACS) on young adults with SUD is not well-documented. We aimed to investigate the impact of ACS on young adults with SUD by comparing demographics, comorbidities, and in-hospital outcomes between those with and without ACS.

Methods:
We used the 2020 National Inpatient Sample (NIS) database to identify hospitalizations of young adults (18-44 years) with SUD and categorized them into those with and without ACS using ICD-10 codes. We compared demographics, comorbidities, all-cause mortality (ACM), and cardiogenic shock between the two groups. Multivariable regression analysis was performed to compare outcomes.

Results:
A total of 4,132,379 weighted hospitalizations of young adults with SUD were included in our study, of which 0.7% (n=30,955) had ACS. The population in the ACS group was older (median age 37 years vs. 32 years), more often had males (71.5% vs. 52.2%) and blacks (26.3% vs. 20.6%), and less often consisted of whites (56.7% vs 64.5%) compared to the no-ACS group. The ACS group had higher rates of hyperlipidemia, hypertension, diabetes, obesity, and peripheral vascular disease compared to the no-ACS group. Interestingly, tobacco and alcohol use disorders were more common in the no-ACS group (Table 1). The ACS group was also associated with higher hospital costs. Patients with ACS suffered significantly higher odds of ACM (aOR 10.16, 95% CI 8.96-11.53) as compared to those without ACS. Over the five years from 2016 to 2020, the rates of ACS admissions among young adults with SUD remained largely unchanged. (all p<0.001).

Conclusion:
In this large nationwide analysis, ACS was associated with a significantly higher risk of ACM in young adults with SUD. Further research is essential to validate this data and develop effective strategies to improve outcomes for this vulnerable population.