Does cannabis use affect how long psychosis goes untreated?

A study of 62 first-episode psychosis patients found that cannabis use did not affect the duration of untreated psychosis, but both cannabis use and longer untreated periods were independently associated with more dissociative symptoms at onset and over time.

Ricci, Valerio et al.·International journal of environmental research and public health·2021·Preliminary EvidenceProspective Cohort
RTHC-03456Prospective CohortPreliminary Evidence2021RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Prospective Cohort
Evidence
Preliminary Evidence
Sample
Not reported

What This Study Found

Cannabis use did not significantly affect the duration of untreated psychosis (DUP). However, both cannabis use and longer DUP were independently associated with higher dissociative symptoms at onset and over the 6-month follow-up period. Longer DUP was associated with worse overall symptoms as expected.

Key Numbers

62 FEP patients; cannabis did not affect DUP length; both cannabis and longer DUP independently associated with dissociative symptoms; effects persisted over 6 months

How They Did This

Prospective study of 62 FEP patients with and without CUD from Italian psychiatric hospitals (2014-2019). Divided by DUP duration. Assessed at treatment initiation, 3 months, and 6 months using PANSS, GAF, and DES-II.

Why This Research Matters

Duration of untreated psychosis is one of the strongest predictors of long-term outcomes. Finding that cannabis independently contributes to dissociative symptoms, separate from DUP effects, suggests cannabis adds a distinct burden on top of treatment delay.

The Bigger Picture

The convergence of cannabis use and treatment delay on dissociative symptoms through independent pathways suggests that early intervention programs need to address both factors. Reducing DUP alone may not fully resolve the additional dissociative burden created by cannabis use.

What This Study Doesn't Tell Us

Small sample (62 patients). Potential selection bias in treatment-seeking population. DUP is inherently difficult to measure accurately. Cannot determine if dissociative symptoms preceded or resulted from cannabis use.

Questions This Raises

  • ?Would addressing cannabis use during the untreated period improve outcomes independently of reducing DUP?
  • ?Do dissociative symptoms serve as a marker for cannabis-influenced psychosis?
  • ?Could screening for dissociation help identify cannabis-related cases?

Trust & Context

Key Stat:
Cannabis and DUP: independent effects on dissociation
Evidence Grade:
Prospective design with 6-month follow-up but small sample and potential measurement challenges.
Study Age:
Published in 2021; the role of dissociation as a marker of cannabis-influenced psychosis is an emerging research area.
Original Title:
Duration of Untreated Disorder and Cannabis Use: An Observational Study on a Cohort of Young Italian Patients Experiencing Psychotic Experiences and Dissociative Symptoms.
Published In:
International journal of environmental research and public health, 18(23) (2021)
Database ID:
RTHC-03456

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-ControlFollows or compares groups over time
This study
Cross-Sectional / Observational
Case Report / Animal Study

Enrolls participants and follows them forward in time.

What do these levels mean? →

Frequently Asked Questions

Does cannabis delay treatment for psychosis?

In this study, cannabis use did not affect how long psychosis went untreated before treatment began. However, both cannabis use and longer untreated periods independently contributed to more dissociative symptoms.

Why do dissociative symptoms matter?

Dissociation, including feeling detached from reality, may indicate a more complex form of psychosis. This study found it was elevated by both cannabis use and treatment delay, suggesting it could be a marker for worse outcomes.

Read More on RethinkTHC

Cite This Study

RTHC-03456·https://rethinkthc.com/research/RTHC-03456

APA

Ricci, Valerio; Martinotti, Giovanni; Ceci, Franca; Chiappini, Stefania; Di Carlo, Francesco; Burkauskas, Julius; Susini, Ottavia; Luciani, Debora; Quattrone, Diego; De Berardis, Domenico; Pettorruso, Mauro; Maina, Giuseppe; Di Giannantonio, Massimo. (2021). Duration of Untreated Disorder and Cannabis Use: An Observational Study on a Cohort of Young Italian Patients Experiencing Psychotic Experiences and Dissociative Symptoms.. International journal of environmental research and public health, 18(23). https://doi.org/10.3390/ijerph182312632

MLA

Ricci, Valerio, et al. "Duration of Untreated Disorder and Cannabis Use: An Observational Study on a Cohort of Young Italian Patients Experiencing Psychotic Experiences and Dissociative Symptoms.." International journal of environmental research and public health, 2021. https://doi.org/10.3390/ijerph182312632

RethinkTHC

RethinkTHC Research Database. "Duration of Untreated Disorder and Cannabis Use: An Observat..." RTHC-03456. Retrieved from https://rethinkthc.com/research/ricci-2021-duration-of-untreated-disorder

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.