Background: The variations in proinflamatory cytokine levels have been associated with schizophrenia (SCH), duration of illness,
psychopathology and treatment. The aim of the study was to investigate serum levels of interleukin-6 (IL-6) and tumor necrosis factoralpha
(TNF-α) in schizophrenic patients during exacerbation and remission, and its association with course of illness and therapy.
Subjects and methods: We measured serum levels of IL-6 and TNF-α in 43 schizophrenic patients in exacerbation and remission
and compared them to 29 healthy controls, matched by sex, age, body mass index (BMI) and smoking habits. The severity of
psychopathology was assessed using the Positive and Negative Syndrome Scale (PANSS).
Results: There was no difference in levels of IL-6 and TNF-α in exacerbation compared to remission in schizophrenic patients.
IL-6 was higher and TNF-α was lower in schizophrenic patients in both exacerbation and remission in comparison with healthy
controls. TNF-α in exacerbation was in negative correlation with IL-6 in remission. No statistical significance was found between
levels of cytokines and sex, age, BMI, smoking habits, antipsychotic medication, duration of treatment and duration of illness. IL-6
levels were in positive correlation with the age of onset and the duration of untreated psychosis. In schizophrenic patients on
adjunctive treatment with mood stabilizers, TNF-α levels increased in remission.
Conclusion: Our results suggest that the connection between schizophrenia, cytokines and medication is multifaceted, and not
necessarily linear. Adjunct mood stabilizers not only ameliorate psychopathology, but might convey immunomodulatory effects as
well. Further longitudinal studies could elucidate potential beneficial effect of combined therapy in treatment of SCH
