Cannabis users with first psychosis had more excitement symptoms initially but responded better to treatment | Research

The takeaway

Among 175 antipsychotic-naive first-episode psychosis patients, those with recent cannabis use showed higher excitement symptoms and worse functioning at baseline, but had better treatment response for excitement and positive symptoms at 10-week follow-up.

Psychiatrists treating first-episode psychosis, early intervention services, and researchers studying cannabis-psychosis subtypes.

Better treatment response

What the researchers found

Acute cannabis users had higher excitement symptoms and worse functioning at baseline. However, at 10-week follow-up, they showed higher response rates for excitement and positive symptoms than non-users. More days of recent cannabis use predicted worse functionality at baseline but not at follow-up, suggesting the acute cannabis effects resolved with treatment.

Why it matters

Studying antipsychotic-naive patients eliminates a major confound in psychosis research. The finding that cannabis-related symptoms resolve well with treatment suggests they may represent a pharmacologically modifiable component of the psychotic presentation.

The numbers in context

175 patients at baseline, 99 at follow-up. All antipsychotic-naive. Acute cannabis users: higher excitement symptoms, worse baseline functioning. Better 10-week response for excitement and positive symptoms. Cannabis effects on functioning resolved by follow-up.

How the study worked

Prospective cohort study in Sao Paulo, Brazil. 175 antipsychotic-naive first-episode psychosis patients assessed at baseline, 99 reassessed at 10-week follow-up. Cannabis exposure variables: acute use, lifetime use, age at first use.

What this study cannot tell us

Significant attrition (175 to 99 at follow-up). Self-reported cannabis use. Short 10-week follow-up. Brazilian population may not generalize. Cannot determine whether the better response reflects a different illness subtype or resolution of acute cannabis effects.

How to read the evidence

Rated moderate because this is a prospective study of antipsychotic-naive patients (eliminating a key confound), though attrition and short follow-up are limitations.

When this study was published

Published in 2019.

The bigger picture

The better treatment response in cannabis-using FEP patients is consistent with the theory that cannabis-precipitated psychosis may be a distinct and potentially more treatable subtype, at least in the short term.

Questions still open

Would the treatment advantage persist with longer follow-up? Does cannabis cessation improve outcomes further? Could excitement symptoms at FEP presentation serve as a clinical marker for recent cannabis use?

Common questions

Does cannabis use affect psychosis treatment response?

In this study, patients with recent cannabis use at their first psychotic episode actually responded better to treatment at 10 weeks, particularly for excitement and positive symptoms.

Should clinicians look for cannabis use in first psychosis?

Higher excitement symptoms at first psychotic presentation may indicate recent cannabis use. This is clinically relevant because these symptoms appear to respond well to standard treatment.

Read the original research

Cannabis acute use impacts symptoms and functionality in a cohort of antipsychotic naïve First Episode of Psychosis individuals.

Schizophrenia research. Cognition, 16, 12-16

View on PubMed ↗Publisher’s paper ↗

Citation

Coutinho, Luccas S; Honorato, Hianna; Higuchi, Cinthia H; Cavalcante, Daniel A; Belangeiro, Sintia; Noto, Mariane; Bressan, Rodrigo A; Cordeiro, Quirino; Noto, Cristiano; Gadelha, Ary. (2019). Cannabis acute use impacts symptoms and functionality in a cohort of antipsychotic naïve First Episode of Psychosis individuals.. Schizophrenia research. Cognition, 16, 12-16. https://doi.org/10.1016/j.scog.2018.10.002