Syndrome inflammatoire chez les schizophrènes toxicomanes
Schizophrenia is a psychosis which presents a frequent comorbidity with substance use disorders (SUD) and with various immune alterations. Using meta-analysis, we have demonstrated previously establishment of an inflammatory syndrome in schizophrenia patients, illustrated by elevated circulating levels of IL-6 (a pro-inflammatory cytokine), sIL-2R (marker of immune activation) and IL-1RA (an anti-inflammatory cytokine). SUD is also associated with dysregulation of inflammatory cytokines, but the effects may depend on the type of substance of abuse. The goal of this project was: 1) To measure plasma concentrations of inflammatory cytokines in schizophrenia patients with comorbid SUD, before, during and after treatment with an atypical antipsychotic, quetiapine; and 2) To perform correlation studies between plasma concentrations of inflammatory cytokines and clinical symptoms, including positive and negative symptoms, cognition, depression and substance use. Relative to normal controls, patients with a dual diagnosis showed increased plasma concentrations of IL-6, IL-1RA, sIL-2R, and IL-8 at baseline, IL-1RA increases being the most important. Quetiapine treatment did not influence plasma cytokine concentrations, except sIL-2R which increased further. Moderate positive correlations were found between IL-6 and depression, IL-6 and alcohol, IL-1RA and cognition, IL-8 and depression, IL-8 and alcohol and between sIL-2R and cannabis. This study demonstrates that the immune and inflammatory response is activated in schizophrenia patients with comorbid SUD. Furthermore, SUD may play a facilitating or potentiating role in the increases in peripheral levels of IL-1RA. Ongoing studies in different patient populations with schizophrenia with or without SUD, and patients with SUD alone will help elucidate the role of different substances of abuse in the inflammatory syndrome in schizophrenia, as well as the clinical and therapeutic relevance of this syndrome.
IL-6 IL-1RA sIL-2R IL-8 IL-17 Schizophrenia Drug addiction Quetiapine clinical Symptoms Cognition and Depression