Heavy cannabis use was linked to lower BDNF levels in first-episode psychosis patients but not in healthy volunteers
In antipsychotic-naive first-episode psychosis patients, heavy cannabis use was associated with lower brain-derived neurotrophic factor (BDNF) levels, a relationship not seen in healthy controls.
Quick Facts
What This Study Found
Among 70 drug-naive first-episode psychosis patients and 57 healthy volunteers, cannabis use was associated with reduced BDNF levels only in the psychosis group. Heavy cannabis use also correlated with younger age in patients. In healthy volunteers, cannabis use was linked to tobacco use but not to BDNF levels.
Key Numbers
70 first-episode psychosis patients (antipsychotic-naive). 57 healthy volunteers. High cannabis use was associated with lower BDNF in patients but not controls. High cannabis use also correlated with younger age in patients.
How They Did This
Cross-sectional study of 70 antipsychotic-naive first-episode psychosis patients and 57 healthy volunteers. Blood samples analyzed for BDNF by ELISA. Substance use, clinical diagnosis, and demographic variables collected via structured clinical interview.
Why This Research Matters
BDNF supports neuron health and plasticity. Finding that cannabis lowers BDNF specifically in psychosis patients suggests a biological mechanism by which cannabis may worsen outcomes in vulnerable individuals.
The Bigger Picture
The selective effect in psychosis patients, but not healthy volunteers, suggests that the biological context matters. The same exposure may have different neurobiological consequences depending on underlying vulnerability.
What This Study Doesn't Tell Us
Cross-sectional design cannot determine causation. Peripheral BDNF levels may not reflect brain BDNF. Cannabis use was self-reported. Relatively small sample sizes.
Questions This Raises
- ?Does cannabis-related BDNF reduction contribute to worse psychosis outcomes?
- ?Would BDNF levels recover if patients stopped using cannabis?
- ?Is the relationship specific to certain cannabis components like THC?
Trust & Context
- Key Stat:
- Cannabis-BDNF link found in psychosis patients but not healthy controls
- Evidence Grade:
- Cross-sectional study with a meaningful comparison group, but small sample and cannot establish causation.
- Study Age:
- 2020 study. Adds to growing evidence on differential effects of cannabis in psychosis-vulnerable populations.
- Original Title:
- Cannabis use influence on peripheral brain-derived neurotrophic factor levels in antipsychotic-naïve first-episode psychosis.
- Published In:
- European archives of psychiatry and clinical neuroscience, 270(7), 851-858 (2020)
- Authors:
- Toll, A, Bergé, D, Burling, K, Scoriels, L, Treen, D, Monserrat, C, Marmol, F, Duran, X, Jones, P B, Pérez-Solà, V, Fernandez-Egea, E, Mané, A
- Database ID:
- RTHC-02881
Evidence Hierarchy
A snapshot of a population at one point in time.
What do these levels mean? →Frequently Asked Questions
What is BDNF?
Brain-derived neurotrophic factor (BDNF) is a protein that supports nerve cell growth, survival, and plasticity. Low BDNF levels have been linked to several psychiatric and neurological conditions.
Why were these patients antipsychotic-naive?
Studying patients before they started antipsychotic medication eliminates the confounding effect of these drugs, which can independently affect BDNF levels.
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Cite This Study
https://rethinkthc.com/research/RTHC-02881APA
Toll, A; Bergé, D; Burling, K; Scoriels, L; Treen, D; Monserrat, C; Marmol, F; Duran, X; Jones, P B; Pérez-Solà, V; Fernandez-Egea, E; Mané, A. (2020). Cannabis use influence on peripheral brain-derived neurotrophic factor levels in antipsychotic-naïve first-episode psychosis.. European archives of psychiatry and clinical neuroscience, 270(7), 851-858. https://doi.org/10.1007/s00406-020-01117-y
MLA
Toll, A, et al. "Cannabis use influence on peripheral brain-derived neurotrophic factor levels in antipsychotic-naïve first-episode psychosis.." European archives of psychiatry and clinical neuroscience, 2020. https://doi.org/10.1007/s00406-020-01117-y
RethinkTHC
RethinkTHC Research Database. "Cannabis use influence on peripheral brain-derived neurotrop..." RTHC-02881. Retrieved from https://rethinkthc.com/research/toll-2020-cannabis-use-influence-on
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.