Medical cannabis dispensary users had high rates of mental illness when properly assessed

When 100 medical cannabis dispensary users were assessed with structured clinical interviews, lifetime mental illness prevalence was high, with particularly elevated rates of anxiety disorders and substance abuse/dependence.

Yau, Jade C et al.·BMC psychiatry·2019·Moderate EvidenceCross-Sectional
RTHC-02361Cross SectionalModerate Evidence2019RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Cross-Sectional
Evidence
Moderate Evidence
Sample
Not reported

What This Study Found

Using the MINI structured clinical interview, lifetime prevalence of mental illness was high. Current psychiatric disorder rates were low for mood disorders but high for anxiety disorders and substance abuse/dependence. Cannabis use patterns differed between psychiatric conditions. Many subjects endorsed psychological symptoms on standardized measures (stress, fatigue, sleep disturbance, depression, somatic symptoms, pain).

Key Numbers

100 medical cannabis users. Structured MINI interview administered to all. Multiple standardized questionnaires completed. High lifetime mental illness prevalence. Low current mood disorder rates. High anxiety and substance disorder rates.

How They Did This

Cross-sectional study of 100 medical cannabis users recruited from a community dispensary. All completed the MINI structured clinical interview plus standardized questionnaires (Perceived Stress Scale-10, PROMIS Fatigue and Sleep scales, Beck Depression Inventory, PHQ-15, Brief Pain Inventory).

Why This Research Matters

Most studies of dispensary users rely on self-report checklists. Using validated clinical instruments provides a more rigorous picture of mental health in this population.

The Bigger Picture

Whether cannabis use contributes to mental health problems or people with mental health problems are drawn to cannabis cannot be determined from this design, but the high co-occurrence is clinically important either way.

What This Study Doesn't Tell Us

Cross-sectional design. Single dispensary. No control group. Cannot determine causation. Selection bias (dispensary users who agreed to participate). Sample may not represent all medical cannabis users.

Questions This Raises

  • ?Are dispensary users getting appropriate mental health care alongside their cannabis use?
  • ?Should dispensaries screen for psychiatric conditions?

Trust & Context

Key Stat:
High anxiety disorder and substance abuse rates
Evidence Grade:
Rigorous clinical assessment instruments, but cross-sectional single-site design without a control group.
Study Age:
2019 study.
Original Title:
Characterization of mental health in cannabis dispensary users, using structured clinical interviews and standardized assessment instruments.
Published In:
BMC psychiatry, 19(1), 335 (2019)
Database ID:
RTHC-02361

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study

A snapshot of a population at one point in time.

What do these levels mean? →

Frequently Asked Questions

Do medical cannabis users have mental health problems?

In this study of 100 dispensary users assessed with clinical interviews, lifetime mental illness rates were high, particularly for anxiety disorders and substance abuse/dependence. Whether cannabis contributed to or resulted from these conditions is unknown.

How was mental health assessed in this study?

Unlike most dispensary studies that use self-report checklists, this study used the MINI structured clinical interview (the same tool used in clinical drug trials) plus multiple validated questionnaires.

Read More on RethinkTHC

Cite This Study

RTHC-02361·https://rethinkthc.com/research/RTHC-02361

APA

Yau, Jade C; Yu, Shu Min; Panenka, William J; Pearce, Hadley; Gicas, Kristina M; Procyshyn, Ric M; MacCallum, Caroline; Honer, William G; Barr, Alasdair M. (2019). Characterization of mental health in cannabis dispensary users, using structured clinical interviews and standardized assessment instruments.. BMC psychiatry, 19(1), 335. https://doi.org/10.1186/s12888-019-2324-z

MLA

Yau, Jade C, et al. "Characterization of mental health in cannabis dispensary users, using structured clinical interviews and standardized assessment instruments.." BMC psychiatry, 2019. https://doi.org/10.1186/s12888-019-2324-z

RethinkTHC

RethinkTHC Research Database. "Characterization of mental health in cannabis dispensary use..." RTHC-02361. Retrieved from https://rethinkthc.com/research/yau-2019-characterization-of-mental-health

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.