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The following is a summary of “Effects of 6-week olanzapine treatment on serum IL-2, IL-4, IL-8, IL-10, and TNF-α levels in drug-naive individuals with first-episode schizophrenia,” published in the October 2024 issue of Psychiatry by Zhao et al.

Schizophrenia involves inflammation, with interleukin (IL)-2, IL-4, IL-8, IL-10, and tumor necrosis factor-alpha (TNF-α) linked to its pathogenesis, but data on cytokine levels after antipsychotic treatment are inconsistent. 

Researchers conducted a retrospective study to examine inflammatory factor changes and their relationship to clinical symptom improvements before and after olanzapine treatment in drug-naive patients with first-episode schizophrenia. 

They recruited 142 hospitalized patients with first-episode schizophrenia and 100 healthy controls. Blood samples were collected to measure serum levels of IL-2, IL-4, IL-8, IL-10, and TNF-α using an enzyme cycling assay. Clinical symptoms were assessed at baseline and after 6 weeks of olanzapine treatment using the Positive and Negative Syndrome Scale (PANSS). 

The results showed that individuals with schizophrenia had lower IL-8 and higher IL-10 levels than healthy controls (P<0.001). Positive correlations were found between serum IL-2 and IL-10 levels and each PANSS subscale (all P<0.05). A negative correlation was observed between IL-8 levels and the PANSS negative score (r = − 0.172, P=0.040). After 6 weeks of treatment, patients had lower IL-8 levels (P<0.001) and higher IL-10 and TNF-α levels (all P<0.05) compared to baseline. IL-10 was identified as an independent risk factor for outcomes (P=0.02, OR = 2.327). Serum IL-2, IL-10, and TNF-α levels were lower, and IL-8 was higher (P<0.001) in healthy controls compared to both the “response” and “no-response” treatment groups. 

The study concluded that serum IL-2, IL-8, IL-10, and TNF-α levels may play a role in the pathophysiology of schizophrenia and are associated with the effects of olanzapine treatment. 

Source: bmcpsychiatry.biomedcentral.com/articles/10.1186/s12888-024-06163-7