Immune dysfunction and childhood trauma in schizophrenia spectrum disorders

Abstract

Schizophrenia spectrum disorders (SSS) is a group of disorders in which patients suffer from various symptoms such as delusions and hallucinations, as well as cognitive symptoms, depressive symptoms and negative symptoms (such as social withdrawal behaviour and apathy). The cause and underlying mechanisms involved in SSS are not precisely known. One hypothesis is that dysfunction of the immune system of the brain plays a role in the onset or perpetuation of symptoms. Some studies suggest that antipsychotics may affect the immune system of the brain positively and that this mechanism contributes to their working mechanism.The first part of this thesis consists of animal studies in which the effects of antipsychotics on immune dysfunction in the brains of rats were investigated using positron emission tomography (PET) scans. We found no or small effects, but methodological limitations make it difficult to draw conclusions.The second part of the study investigated the association between childhood trauma, immune dysfunction and negative and depressive symptoms in SSS patients. We found that childhood trauma leads to more severe depressive and negative symptoms and that childhood sexual abuse is more common in women.Based on the studies conducted, necessary elements of follow-up research were identified. Existing PET tracers are not specific enough to investigate immune dysfunction of the brain. Therefore, research into new PET tracers is important. In addition, it is important to look at men and women with SSS separately, because of the male-female differences in SSS patients.