Pre- and post-treatment levels of plasma cytokines in drug-naive patients with first-episode psychosis: a meta-analysis

First-episode psychosis is defined by the first treatment contact, with no previous antipsychotic medication use, due to the occurrence of psychotic symptoms or a psychotic episode. Psychosis involves any diagnosis included in the schizophrenia disorder cluster. Schizophrenia and other psychotic disorders are severe mental disorders characterized by delusions, hallucinations, disorganized speech and behaviour, and other symptoms that cause poor clinical outcomes and severe impairment in psychosocial functioning. Aetiology of schizophrenic disorders remain not entirely elucidated. Among possible causes, immunological factors have been increasingly involved in the pathogenesis and course of schizophrenia. The inflammatory system may trigger or modulate the course of schizophrenic disorders. Modifications in cytokine levels in schizophrenia and related psychotic disorders have been repeatedly described. However, the effect of antipsychotics on cytokine levels in drug naive patients remains, incompletely explored yet. The aim of this meta-analysis will be to estimate the effect of antipsychotic treatment on plasma levels of candidate, relevant peripheral cytokines in drug-naive patients with first-episode psychosis.