Association between adverse childhood experiences and suicidal behavior in schizophrenia spectrum disorders: A systematic review and meta-analysis

Assessing and managing suicide behaviors is highly relevant to individuals with schizophrenia spectrum disorders. Our study aims to assess the association between adverse childhood experiences and suicidal behaviors in individuals with schizophrenia spectrum disorders. We included observational studies comparing the probability of suicide behaviors in adults with schizophrenia spectrum disorders exposed and unexposed to adverse childhood experiences. Odds ratio estimates were obtained by pooling data using a random-effects pairwise meta-analysis. Standardized criteria were used to assess the strength of the association of the pooled estimate. We found 21 eligible studies reporting outcomes for 6257 individuals from 11 countries. The primary outcome revealed an association between any suicidal behavior and adverse childhood experiences, which resulted "highly suggestive" according to validated Umbrella Criteria. Similarly, a positive association was confirmed for suicidal ideation and suicide attempt and for any subtype of adverse childhood experience. This meta-analysis showed that exposure to adverse childhood experiences strongly increases the probability of suicide behaviors in people with schizophrenia spectrum disorders

Cytokines in schizophrenia: hope or hype?

Although there is a cumulative evidence for the inflammation pathophysiology in schizophrenia, it has not been conclusively proven yet. One reason for this is the lack of studies that have controlled for major confounding factors such as obesity, smoking, antipsychotic use, and stress. The studies in which the major confounding factors were controlled were done in subjects in acute relapse and in treatment-resistant schizophrenia. To date, no studies have been done in stable outpatients with schizophrenia controlling for major confounding factors. Data on cerebrospinal fluid cytokines in large sample independent of confounding factors are also lacking. The efficacy signal from anti-inflammatory medications in schizophrenia has been modest. In this study, the inconsistent and nonvalidated cytokine findings independent of the confounding factors are discussed

Methodological Issues in Cytokine Measurement in Schizophrenia.

There is mounting evidence that inflammation is a major factor in the pathophysiology of schizophrenia. Inflammatory status is commonly ascertained by measuring peripheral cytokine concentrations. An issue concerning research on inflammation and schizophrenia relates to assay methodology. Enzyme-linked immunosorbent assay (ELISA) is the most widely used and the gold standard method used to measure cytokine concentrations. ELISA has a number of limitations. Both ELISA and multiplex are limited by not being able to distinguish between bioactive and inactive molecules and the matrix and heterophilic (auto-) antibody interference. Multiplex assays when combined with gene expression analysis and flow cytometry techniques such as fluorescence-activated cell sorting may be useful to detect abnormalities in specific immune pathways. Peripheral blood mononuclear cells cultures, to evaluate in vitro lipopolysaccharide-induced cytokine production, may be a better technology than measuring cytokines in the serum. The purpose of this paper is to shed light on major methodological issues that need to be addressed in order to advance the study of cytokines in schizophrenia. We make a few recommendations on how to address these issues