Evaluating Cardiotoxicity and Factors Associated with In-Hospital Mortality Among Emergency Department Patients with Substance Use Disorder: An 11-year retrospective study.

OBJECTIVE

Substance use disorder (SUD)-related emergencies are increasing globally, with cardiotoxicity contributing substantially to morbidity and mortality. This study evaluated cardiotoxicity patterns and factors associated with in-hospital mortality among adults with SUD presenting to the emergency department (ED).

METHODS

This retrospective observational study was conducted from January 2014 to December 2024 at Sultan Qaboos University Hospital, University Medical City, Muscat, Oman. Adults aged ≥18 years with SUD and positive urine drug screening (UDS) were included if they had elevated troponin (>14 ng/L), electrocardiographic abnormalities or echocardiographic structural dysfunction. Clinical, laboratory, imaging, management and outcome data were analysed.

RESULTS

A total of 4,400 ED medical records were reviewed; 478 patients had SUD and 78 (16.3%) met the inclusion criteria (mean age = 40.8 ± 12.3 years, 92.3% male). Opiate-class positivity on UDS was the most frequent finding (62.8%), followed by methamphetamine (29.5%). Sinus tachycardia (41.0%) and ST-T changes (15.4%) were the most common electrocardiographic abnormalities. Elevated troponin was present in 87.2%. Overall, in-hospital mortality was 15.4%. Hypokinesia (odds ratio [OR] = 5.12, 95% confidence interval [CI]: 1.08-24.22; P = 0.040) and left ventricular impairment (OR = 6.14, 95% CI: 0.95-39.88; P = 0.057) showed the strongest mortality associations.

CONCLUSION

Among ED patients with SUD, positive UDS and cardiotoxicity, structural cardiac dysfunction was associated with higher in-hospital mortality. These findings support early cardiovascular assessment, including electrocardiography, troponin testing and selective echocardiography, in high-risk patients with substance-related toxicity.