Cannabis use patterns predicted worse outcomes in first-episode psychosis despite early intervention | Research

The takeaway

In patients with first-episode psychosis, continued cannabis use predicted worse symptom and functional trajectories, and early intervention services did not fully offset cannabis-related disadvantages.

Early psychosis intervention teams, addiction psychiatrists, and mental health service planners.

Continued cannabis use predicted worse FEP outcomes even with early intervention

What the researchers found

Cannabis use patterns were characterized among FEP patients, and continued use was associated with worse symptomatic and functional outcomes. Early intervention services improved overall outcomes but did not fully compensate for the negative trajectory associated with ongoing cannabis use.

Why it matters

Cannabis use is extremely common in first-episode psychosis populations. If ongoing use undermines even the best available treatment (early intervention services), addressing cannabis use must be a core component of FEP care.

The numbers in context

RAISE study dataset. Cannabis use patterns characterized. Continued use associated with worse symptom and functional trajectories. Early intervention services partially but not fully offset cannabis-related disadvantages.

How the study worked

Longitudinal analysis of the Recovery After an Initial Schizophrenia Episode (RAISE) dataset. Characterized cannabis use patterns and examined their relationship with clinical outcomes, including interactions with early intervention services.

What this study cannot tell us

Observational longitudinal data from a clinical trial context. Cannabis use patterns self-reported. Confounding by illness severity (sicker patients may use more cannabis). Treatment engagement may differ between cannabis users and non-users.

How to read the evidence

Longitudinal data from a well-characterized clinical trial cohort. Observational analysis limits causal claims.

When this study was published

Published 2023.

The bigger picture

Early intervention for psychosis has been one of the most important advances in mental health care. The finding that cannabis use limits its effectiveness adds urgency to integrating substance use treatment within early psychosis programs.

Questions still open

Would integrated cannabis cessation within early psychosis intervention improve outcomes? At what point after psychosis onset does cannabis cessation produce the best results?

Common questions

Does cannabis use affect recovery from psychosis?

In this study, continued cannabis use during treatment for first-episode psychosis was associated with worse symptom improvement and poorer functional outcomes over time. Early intervention services helped overall but could not fully compensate for the negative effects of ongoing cannabis use.

Should people with psychosis stop using cannabis?

This data suggests continued cannabis use after a first psychotic episode is associated with worse recovery. Integrating cannabis use reduction into psychosis treatment appears important, though the study cannot prove that stopping cannabis alone would improve outcomes.

Read the original research

Relationship between patterns of cannabis use and functional and symptomatic trajectories in first-episode psychosis.

European archives of psychiatry and clinical neuroscience, 273(4), 765-778

View on PubMed ↗Publisher’s paper ↗

Citation

Wright, Abigail C; Browne, Julia; Cather, Corinne; Meyer-Kalos, Piper; Mueser, Kim T. (2023). Relationship between patterns of cannabis use and functional and symptomatic trajectories in first-episode psychosis.. European archives of psychiatry and clinical neuroscience, 273(4), 765-778. https://doi.org/10.1007/s00406-022-01441-5