Serum Interleukin-6 in Schizophrenia: Associations with Clinical and Sociodemographic Characteristics.

backgroundRecently a significant part of schizophrenia studies have been focused on the role of cytokines, especially interleukin-6 (IL-6). Some authors have suggested a pathogenetic role for IL-6 in schizophrenia and concluded that therapy that centers on suppressing IL-6 activity may prove beneficial for certain categories of patients with the disorder. However, many questions about whether the changes in IL-6 levels in schizophrenia are primary, related to symptoms or caused by therapy, are concomitant metabolic disorders, are related to smoking or other secondary factors remain unanswered.

aimTo assess the level of serum IL-6 in patients with schizophrenia in comparison with healthy controls, as well as to study its association with clinical and socio-demographic characteristics.

methodsSome 125 patients with schizophrenia and 95 healthy volunteers were examined. The evaluation of IL-6 was performed by enzyme immunoassay. All patients were assessed using standardized psychometric instruments. Information from patient medical records on the course of the disease and treatment was analyzed.

resultsThe level of IL-6 was significantly higher in the patients than in the healthy volunteers (z=2.58;

conclusionThe study confirmed that there are associations between the serum IL-6 level and schizophrenia, the age of the patient, duration of the disease and how late in one's life cycle it began manifesting itself, as well as a number of clinical characteristics. Considering that IL-6 is associated with a wide range of symptoms that are loosely controlled by antipsychotics, this biochemical marker needs to be studied to look into how closely its level tracks with an unfavorable course of schizophrenia. That would require further prospective studies.