A test of self-medication hypothesis for drug use in homeless persons: the role of severe mental illness

ABSTRACT

The purpose of this study was to test the self-medication hypothesis of drug use in a sample of homeless persons. A serial mediation model was tested to examine the effects of recent victimization on trauma-related symptom severity, and the effects of trauma-related symptom severity on severity of severe mental illness (SMI) symptoms, and finally the effects of severity of SMI symptoms on illicit drug use. The final sample for the study included 164 participants who were assessed prospectively at both baseline and 6-month post-baseline. It was hypothesized that SMI would mediate the pathways for self-medication. Structural Equations Modelling analyses revealed that current trauma-related symptom severity mediated the relationship between recent victimization and severity of SMI symptoms. Furthermore, SMI symptom severity mediated the relationship between current trauma-related symptom severity, and illicit drug use providing indirect support for the self-medication hypothesis. The findings underscore the importance of assessing and providing for trauma-informed care to persons with SMI seeking services for co-occurring substance use disorders.

KEYWORDS:

• Homelessness
• victimization
• PTSD
• SMI
• drug use

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by Substance Abuse and Mental Health Services Administration [Grant Number TI025617].

Notes on contributors

Pallavi Nishith

Pallavi Nishith, Ph.D. has a primary appointment as Staff Psychologist at Places for People, Inc. In this role she provides clinical services in treating trauma related Posttraumatic Stress Disorder (PTSD) in persons diagnosed with a serious mental illness (SMI) using cognitive behavioral therapy (CBT) models of treatment. In addition, she also provides training, and conducts research in the areas of trauma and PTSD in SMI.

Jin Huang

Dr Jin Huang is a professor of social work at Saint Louis University. His research focuses on financial and social support for disadvantaged populations.

Gary A. Morse

Gary A. Morse, Ph.D., is Director, Illume: The Behavioral Health Center of Excellence, Places for People. His research includes burnout prevention interventions for mental health staff and implementation of evidence-based practices for under-served populations with mental health and/or substance use concerns.

Nathaniel Dell

Nathaniel Dell, AM, MSW, LCSW, is Vice President of Knowledge Translation & Impact, Places for People.

Allison Murphy

Allison Murphy, MSW, LCSW is Team Leader, Evaluation, at Places for People. Allison has 5 years of experience in the field including working with those with SMI, substance use, and the unhoused population.

Kim T. Mueser

Kim T. Mueser, Ph.D. is a clinical psychologist and Professor at the Center for Psychiatric Rehabilitation at Boston University. Dr Mueser’s clinical and research interests include family psychoeducation, the treatment of co-occurring psychiatric and substance use disorders, psychiatric rehabilitation for serious mental illnesses, and the treatment of posttraumatic stress disorder.