Cannabis use was linked to elevated inflammatory marker sgp130 in schizophrenia but not bipolar disorder

What the researchers found

Screening 13 plasma inflammatory markers, cannabis users in the schizophrenia group had significantly elevated soluble gp130 (sgp130) compared to non-users (p=0.002, surviving multiple testing correction). This was not found in bipolar disorder. Nominal increases were also seen in IL-1RA, YKL40, CatS, sTNFR1, and BDNF in cannabis-using schizophrenia patients. The differences were not reflected in peripheral immune cell mRNA expression, suggesting a non-immune-cell origin.

Why it matters

sgp130 is an inhibitor of IL-6 trans-signaling, a pro-inflammatory pathway implicated in schizophrenia. If cannabis increases sgp130 specifically in schizophrenia, it may explain why some patients report symptomatic benefit from cannabis: through anti-inflammatory modulation.

The numbers in context

401 SCZ patients; 242 BD patients; sgp130 significantly elevated in cannabis-using SCZ (p=0.002); not in BD; nominal increases in IL-1RA, YKL40, CatS, sTNFR1, BDNF in SCZ cannabis users.

How the study worked

Cross-sectional comparison of 13 plasma inflammatory markers between cannabis users and non-users within schizophrenia (n=401) and bipolar disorder (n=242) groups, with multiple testing correction.

What this study cannot tell us

Cross-sectional; self-reported cannabis use (no dose/frequency data); cannot determine if sgp130 elevation is protective or reactive; medication effects not fully controlled; multiple testing limits interpretation of nominally significant markers.

How to read the evidence

Moderate: large clinical sample with multiple testing correction, but cross-sectional and self-reported cannabis use.

When this study was published

Published 2020.

The bigger picture

The diagnosis-specificity is the key finding. Cannabis appears to interact with the immune system differently in schizophrenia versus bipolar disorder, suggesting the endocannabinoid-immune interaction is modulated by the underlying disease state.

Questions still open

• Is the sgp130 elevation clinically protective in schizophrenia? Would targeting IL-6 trans-signaling directly replicate the anti-inflammatory benefit without cannabis risks?

Common questions

Read the original research

Cannabis Use Is Associated With Increased Levels of Soluble gp130 in Schizophrenia but Not in Bipolar Disorder.

Frontiers in psychiatry, 11, 642

Citation

Szabo, Attila; Akkouh, Ibrahim A; Ueland, Thor; Lagerberg, Trine Vik; Dieset, Ingrid; Bjella, Thomas; Aukrust, Pål; Le Hellard, Stephanie; Stavrum, Anne-Kristin; Melle, Ingrid; Andreassen, Ole A; Djurovic, Srdjan. (2020). Cannabis Use Is Associated With Increased Levels of Soluble gp130 in Schizophrenia but Not in Bipolar Disorder.. Frontiers in psychiatry, 11, 642. https://doi.org/10.3389/fpsyt.2020.00642

Explore the wider topic

• How THC Affects Your Amygdala: The Brain's Threat Detector and Cannabis
• The Anandamide Connection: Your Body's Natural Bliss Molecule
• How Long for Cannabinoid Receptors to Return to Normal
• Cannabis and the Developing Brain: What Every Teenager (and Parent) Should Know
• Why Can't I Enjoy Anything Without Weed? The Science Behind It
• Dopamine Recovery After Quitting Weed: What the Science Says
• The Endocannabinoid System Explained Simply: What It Does and Why It Matters
• Your Endocannabinoid System Explained: Why Withdrawal Happens
• Your Nervous System After Quitting Weed: Fight or Flight
• Using Weed Under 18: What It Does to Your Developing Brain
• What THC Does to Your Brain: Why Withdrawal Happens
• THC and Your Prefrontal Cortex: What Cannabis Does to Your Decision-Making Brain
• Weed, Cortisol, and Stress: What Cannabis Does to Your Stress Hormones
• Weed and Memory: What the Science Says About THC and Your Hippocampus
• Weed and Motivation: Is Amotivational Syndrome Real?
• Weed and Your Nervous System: What THC Actually Does to Your Brain and Body
• How Weed Rewires Your Reward System (And How to Reset It)