Cannabis use changes blood biomarker patterns in people with schizophrenia | Research

The takeaway

Schizophrenia patients who also had cannabis use disorder showed different blood biomarker patterns than those with schizophrenia alone, suggesting distinct underlying mechanisms in dual-diagnosis patients.

Psychiatrists treating dual-diagnosis patients, biomarker researchers, and anyone interested in the biological overlap between cannabis and psychosis.

Biomarkers elevated in schizophrenia were absent in dual-diagnosis patients

What the researchers found

Platelet serotonin 2A receptors, active Akt protein, anandamide, other lipid mediators, and pro-inflammatory IL-6 were all significantly increased in schizophrenia patients. However, patients with both schizophrenia and cannabis use disorder did not show these same elevations, suggesting cannabis use normalizes or alters these biomarkers.

Why it matters

If schizophrenia patients who use cannabis have fundamentally different biomarker profiles, they may need different treatment approaches. These findings could also explain why dual-diagnosis patients often have different clinical trajectories.

The numbers in context

Platelet 5-HT2A and phospho-Akt significantly increased in schizophrenia but not in dual diagnosis. Anandamide, PEA, DEA, and IL-6 significantly increased in schizophrenia but not in dual diagnosis. All comparisons were against age- and sex-matched controls.

How the study worked

Observational study evaluating blood biomarkers (platelet 5-HT2A receptors, Akt protein, endocannabinoids, IL-6) in subjects with schizophrenia, cannabis use disorder, dual diagnosis, or neither condition, matched by age and sex.

What this study cannot tell us

Observational design cannot determine causation. Sample sizes not specified in the abstract. Blood biomarkers may not reflect central nervous system processes. Medication use in schizophrenia patients could confound results.

How to read the evidence

Observational study with novel biomarker findings and matched controls, but lacking clear sample sizes and potential medication confounds.

When this study was published

Published in 2022.

The bigger picture

The idea that cannabis use might normalize some biomarkers that are elevated in schizophrenia is counterintuitive given that cannabis is considered a risk factor for psychosis. It suggests the biology of dual-diagnosis psychosis may differ from schizophrenia alone.

Questions still open

Does cannabis directly suppress these biomarkers, or do dual-diagnosis patients represent a biologically distinct subtype of schizophrenia? Could these blood biomarkers help distinguish different forms of psychosis?

Common questions

Does cannabis change the biology of schizophrenia?

This study found that blood biomarkers elevated in schizophrenia alone (serotonin receptors, Akt, anandamide, IL-6) were not elevated in patients who had both schizophrenia and cannabis use disorder, suggesting different underlying biology.

Could blood tests distinguish types of psychosis?

The distinct biomarker patterns between schizophrenia with and without cannabis use disorder suggest blood-based markers could potentially help differentiate these groups, though this needs further validation.

Read the original research

Cannabis use selectively modulates circulating biomarkers in the blood of schizophrenia patients.

Addiction biology, 27(6), e13233

View on PubMed ↗Publisher’s paper ↗

Citation

Ibarra-Lecue, Inés; Unzueta-Larrinaga, Paula; Barrena-Barbadillo, Rocío; Villate, Aitor; Horrillo, Igor; Mendivil, Begoña; Landabaso, Miguel A; Meana, J Javier; Etxebarria, Nestor; Callado, Luis F; Urigüen, Leyre. (2022). Cannabis use selectively modulates circulating biomarkers in the blood of schizophrenia patients.. Addiction biology, 27(6), e13233. https://doi.org/10.1111/adb.13233