A Retrospective Cohort Study of Hospitalised Patients With First‐Episode Substance‐Induced Psychosis and First‐Episode Psychosis: Comparing Long‐Acting Injectable Antipsychotic Use and Post‐Discharge Outcomes
John D. Eun, Matt Iles‐Shih, Suelynn Ren, Kevin A. Hallgren, Adam KuczynskiABSTRACT
Introduction
Clinicians may not recommend long‐acting injectable antipsychotics (LAI‐APs) for patients diagnosed with first‐episode substance‐induced psychosis (FESIP), despite the risk of transition from FESIP to schizophrenia and the effectiveness of LAI‐AP in early psychosis. We compared LAI‐AP use and post‐discharge outcomes between patients with first‐episode psychosis (FEP) and those with FESIP during their index psychiatric hospitalisation.
Methods
We conducted a retrospective cohort study using electronic health record data from patients aged 18–39 who were discharged from inpatient psychiatry units at a public academic hospital between 2021 and 2024. Outcomes included administration of any LAI‐AP during the index hospitalisation, documented recommendation of any LAI‐AP, psychiatric rehospitalisation and emergency department (ED) encounters after discharge.
Results
The cohort included 90 patients with FEP and 84 patients with FESIP. Only one (1.2%) patient with FESIP received an LAI‐AP compared with 10 (11.1%) with FEP (OR = 0.10, 95% CI = 0.002–0.71); LAI‐AP was recommended to one (1.2%) patient with FESIP compared with 30 (33.3%) with FEP (OR = 0.02, 95% CI = 0.0006–0.16). Rehospitalisation occurred in 41 (45.6%) patients with FEP and 38 (45.2%) with FESIP; post‐discharge ED encounters occurred in 50 (55.6%) and 52 (61.9%) patients, respectively. Time to first rehospitalisation and ED encounter after discharge did not differ between the groups.
Conclusions
Despite similar post‐discharge outcomes between patients with FEP and FESIP, administration or recommendation of an LAI‐AP was rarer among those with FESIP. Our findings highlight uncertainty in treatment decision‐making and support further research to guide early intervention strategies in patients with substance‐induced psychosis.