How substance use and psychosis affect mortality among homeless adults in Vancouver
Among 437 homeless or precariously housed adults in Vancouver, both substance use disorders and psychotic disorders were associated with increased mortality over a 10-year follow-up.
Quick Facts
What This Study Found
Over 10 years of follow-up, participants with co-occurring substance use and psychotic disorders had higher mortality rates than those with either condition alone. Cannabis use was one of several substances assessed, though injection drug use carried the highest mortality risk.
Key Numbers
437 participants; 10-year follow-up period; mortality data linked through provincial vital statistics.
How They Did This
Prospective longitudinal cohort study following 437 homeless or precariously housed adults in Vancouver for up to 10 years, with structured diagnostic interviews at baseline.
Why This Research Matters
Homelessness, substance use, and mental illness often co-occur, but few studies track mortality outcomes over extended periods in this population. The findings highlight the compounding risks when multiple conditions overlap.
The Bigger Picture
This study underscores that addressing substance use or mental illness alone may not be sufficient. The intersection of homelessness, psychosis, and substance use creates compounding vulnerability that requires integrated approaches.
What This Study Doesn't Tell Us
Single city (Vancouver); cannabis use was one of many substances examined and not isolated as an independent risk factor; attrition challenges inherent to studying homeless populations.
Questions This Raises
- ?What specific interventions could reduce mortality in this high-risk population?
- ?How does the legalization of cannabis in Canada affect substance use patterns among homeless individuals?
Trust & Context
- Key Stat:
- 437 homeless adults followed for 10 years
- Evidence Grade:
- Moderate: longitudinal design with diagnostic interviews, but single-city sample and cannabis not isolated from other substances.
- Study Age:
- Published 2016.
- Original Title:
- Associations of substance use, psychosis, and mortality among people living in precarious housing or homelessness: A longitudinal, community-based study in Vancouver, Canada.
- Published In:
- PLoS medicine, 17(7), e1003172 (2020)
- Authors:
- Jones, Andrea A(2), Gicas, Kristina M(3), Seyedin, Sam, Willi, Taylor S, Leonova, Olga, Vila-Rodriguez, Fidel, Procyshyn, Ric M, Smith, Geoffrey N, Schmitt, Toby A, Vertinsky, A Talia, Buchanan, Tari, Rauscher, Alex, Lang, Donna J, MacEwan, G William, Lima, Viviane D, Montaner, Julio S G, Panenka, William J, Barr, Alasdair M, Thornton, Allen E, Honer, William G
- Database ID:
- RTHC-02634
Evidence Hierarchy
Follows a group of people over time to track how outcomes develop.
What do these levels mean? →Frequently Asked Questions
Did cannabis use specifically increase mortality risk?
The study assessed multiple substances together. Cannabis use was part of the broader substance use assessment, but injection drug use, not cannabis specifically, carried the highest mortality risk.
What increased mortality risk most?
The combination of psychotic disorders and substance use disorders together was associated with higher mortality than either condition alone.
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Cite This Study
https://rethinkthc.com/research/RTHC-02634APA
Jones, Andrea A; Gicas, Kristina M; Seyedin, Sam; Willi, Taylor S; Leonova, Olga; Vila-Rodriguez, Fidel; Procyshyn, Ric M; Smith, Geoffrey N; Schmitt, Toby A; Vertinsky, A Talia; Buchanan, Tari; Rauscher, Alex; Lang, Donna J; MacEwan, G William; Lima, Viviane D; Montaner, Julio S G; Panenka, William J; Barr, Alasdair M; Thornton, Allen E; Honer, William G. (2020). Associations of substance use, psychosis, and mortality among people living in precarious housing or homelessness: A longitudinal, community-based study in Vancouver, Canada.. PLoS medicine, 17(7), e1003172. https://doi.org/10.1371/journal.pmed.1003172
MLA
Jones, Andrea A, et al. "Associations of substance use, psychosis, and mortality among people living in precarious housing or homelessness: A longitudinal, community-based study in Vancouver, Canada.." PLoS medicine, 2020. https://doi.org/10.1371/journal.pmed.1003172
RethinkTHC
RethinkTHC Research Database. "Associations of substance use, psychosis, and mortality amon..." RTHC-02634. Retrieved from https://rethinkthc.com/research/jones-2020-associations-of-substance-use
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.