Abstract 224: Clinical Outcomes of Non‐Traumatic Subarachnoid Hemorrhage in Patients with Substance Use Disorder: A TriNetX Analysis
Authors: Jain A. , Wanniarachchige D. , Thorman I. , Sacknovitz A. , Al‐Mufti F. 
Published: January 2025

Introduction/Purpose
Subarachnoid hemorrhage (SAH), an accumulation of blood between the pia and arachnoid mater, is most often caused by non‐traumatic rupture of a cerebral aneurysm. Common risk factors that contribute to the development of SAH include hypertension, smoking, and substance use. There is a well‐documented association between the use of sympathomimetic agents and the development of SAH. However, there is a gap in understanding regarding the clinical outcomes of SAH patients with current and/or past use of other substances, which this study aims to address.

Methods
This retrospective cohort study used the TriNetX Research Network to analyze data from patients with a history of non‐traumatic SAH when at least 18 years of age. Substance use disorders were determined by the ICD‐10 codes F10 to F19, and included a total of 13 substances. Patients with each substance use disorder were compared to patients with no substance use disorders with Cox proportional hazard models. The outcomes of interest that were analyzed included mortality, vasospasm, hydrocephalus, and epilepsy.

Results
A total of 209,970 patients with non‐traumatic SAH were included in the study. In patients with non‐traumatic SAH, substance use disorders were associated with a significantly increased hazard of mortality for alcohol (HR=1.08, [1.04, 1.13]), opiates (HR=1.23, [1.14, 1.32]), stimulants (HR=1.17, [1.05, 1.30]), nicotine (HR=1.04, [1.01, 1.07]), inhalants (HR=1.19, [1.05, 1.36]), and other psychoactive substances (HR=1.221, [1.135, 1.313]). While nicotine dependence (HR=1.273, [1.210, 1.340]) and cannabis dependence (HR=1.255, [1.072, 1.399]) increased the hazard of vasospasm, alcohol (HR=0.916, [0.841, 0.997]) and sedatives (HR=0.705, [0.504, 0.987]) offered significant protection. Similarly, although nicotine dependence (HR=1.08, [1.043, 1.119]) increased the hazard of hydrocephalus, several substance use disorders – including alcohol (HR=0.816, [0.772, 0.863]), opioids (HR=0.830, [0.745, 0.924]), cannabis (HR=0.799, [0.723, 0.882]), sedatives (HR=0.673, [0.545, 0.830]), hallucinogens (HR=0.445, [0.277, 0.717]), and other psychoactive substances (HR=0.730, [0.661, 0.807]) – decreased the hazard of hydrocephalus.

Conclusions
Our study found that substance use disorders in patients with non‐traumatic SAH are associated with a significant increase in the hazard of mortality in alcohol, opioids, stimulants, nicotine, inhalants, and other psychoactive substances. While nicotine and cannabis dependence increased the hazard of vasospasm, alcohol and sedatives offered protection for these patients. Furthermore, while nicotine dependence increased the hazard of hydrocephalus, other substances, including alcohol, opioids, cannabis, sedatives, hallucinogens, and other psychoactive substances, decreased the hazard of hydrocephalus. The findings of our study illuminate the long‐term neurological impact of substance use disorders in patients with non‐traumatic SAH, and can help guide clinical decision‐making and public health education measures to target substance use disorders in the general population.