Effects of Substance Use Disorder on In-Hospital Outcomes of Young Patients Presenting With a Cardiovascular Event: A Nationwide Analysis

Background Substance use is widely prevalent among young adults and is associated with increased cardiovascular morbidity and mortality such as sudden cardiac arrest, acute coronary syndrome, arrhythmias, and cardiomyopathy. However, they are limited studies analyzing the impact of substance use disorder on in-hospital outcomes among young patients with cardiovascular events. Methods All patients aged 18-39 years admitted primarily for major cardiovascular events including acute myocardial infarction (AMI), arrhythmia, cardiac arrest, acute ischemic stroke, and venous thromboembolic events in 2019 were identified in the National Inpatient Sample database. They were then categorized into those with and without concomitant substance use disorder (SUD). The primary outcome was in-hospital mortality. Unadjusted and adjusted analysis was performed on appropriate variables of interest. Results Of 57,985 hospitalizations with cardiac events, 12,115 (20%) of young adults had concomitant SUD. SUD was significantly associated with cardiac arrest (OR 3.3; CI 2.4-4.4), atrial fibrillation (OR 1.5; CI 1.3-1.7), AMI (OR 1.3; CI 1.2-1.6), heart failure (OR 2.6; CI 2.4-3.0) (all p<0.05) despite a lower prevalence of traditional cardiovascular risk factors than non-users. Logistic regression showed acute kidney injury (aOR 1.5; CI 1.3-1.8; p<0.001) and inpatient mortality (aOR 1.6; CI 1.2-2.2; p<0.001) were also significantly higher in young patients presenting with cardiac events and concomitant SUD. There was no difference in the length of stay or incidence of gastrointestinal bleed between the two groups. Conclusion In young patients presenting with a cardiovascular event, concurrent substance use disorder was associated with increased in-hospital mortality despite significantly lower comorbidities.