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

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.

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.

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 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.

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.