Cannabis use at the end of a first-episode psychosis program quadrupled relapse risk | Research

The takeaway

Among 143 people completing a coordinated specialty care program for first-episode psychosis, those still using cannabis at their last visit had four times the odds of relapse and one-third the odds of continuing psychiatric care.

Psychiatrists, first-episode psychosis program staff, and early intervention researchers

4x relapse risk with cannabis use at exit (aOR 4.06)

What the researchers found

Cannabis use at last program contact was associated with a fourfold higher risk of relapse (aOR 4.06, 95% CI 1.56-10.56) and significantly lower rates of outpatient psychiatric follow-up (aOR 0.32, 95% CI 0.12-0.94) in the 12 months after ending coordinated specialty care. Prior emergency/hospitalization during the program also predicted relapse (aOR 4.69).

Why it matters

The transition out of first-episode psychosis programs is a vulnerable period. Identifying cannabis use as a strong predictor of both relapse and disengagement from care provides a clear clinical target.

The numbers in context

143 individuals; cannabis use at last contact: relapse aOR 4.06 (95% CI 1.56-10.56); outpatient follow-up aOR 0.32 (95% CI 0.12-0.94); prior ED/hospitalization: relapse aOR 4.69 (95% CI 1.78-12.34); no racial/ethnic differences in outcomes

How the study worked

Retrospective analysis of 143 individuals with first-episode psychosis who received coordinated specialty care (CSC) between 2014 and 2021. Electronic health records and linked insurance claims data were used to identify relapse (ED visits or hospitalization) and outpatient follow-up in the 12 months after program exit.

What this study cannot tell us

Small sample from a single urban safety-net program; cannot determine if cannabis caused worse outcomes or if people at higher relapse risk are more likely to use cannabis; retrospective design; cannabis use assessed only at last contact, not continuously

How to read the evidence

Small single-center retrospective study with appropriate multivariable adjustment, but limited by sample size and inability to establish causation.

When this study was published

2024 publication analyzing 2014-2021 data

The bigger picture

This study reinforces that cannabis use during first-episode psychosis treatment is not just a concurrent problem but a strong predictor of worse outcomes after treatment ends, particularly reduced engagement in ongoing care.

Questions still open

Would cannabis cessation interventions integrated into first-episode psychosis programs reduce post-program relapse? Is there a threshold of cannabis use below which risk is not elevated?

Common questions

How strongly did cannabis predict relapse after first-episode psychosis treatment?

People still using cannabis at their last program visit had four times the odds of relapse (psychiatric emergency visits or hospitalization) in the following year compared to those not using cannabis, after adjusting for other factors.

Did cannabis use also affect follow-up care?

Yes. Cannabis users had only about one-third the odds of continuing outpatient psychiatric care after leaving the program. This double impact of higher relapse risk combined with lower care engagement makes cannabis use at program exit a particularly concerning finding.

Read the original research

Predictors of relapse and engagement in care one year after ending services in an urban safety net coordinated specialty care program for first episode psychosis.

Schizophrenia research, 264, 140-146

View on PubMed ↗Publisher’s paper ↗

Citation

Hyatt, Andrew; Mullin, Brian; Hasler, Victoria; Madore, Drew; Progovac, Ana M; Cook, Benjamin Lê; DeLisi, Lynn E. (2024). Predictors of relapse and engagement in care one year after ending services in an urban safety net coordinated specialty care program for first episode psychosis.. Schizophrenia research, 264, 140-146. https://doi.org/10.1016/j.schres.2023.12.022