Multiple relapses characterise the course of illness in most patients with schizophrenia, yet the nature of these episodes has not been extensively researched and clinicians may not always be aware of important implications. We critically review selected literature regarding the nature and underlying neurobiology of relapse. Relapse rates are very high when treatment is discontinued, even after a single psychotic episode; a longer treatment period prior to discontinuation does not reduce the risk of relapse; many patients relapse soon after treatment reduction and discontinuation; transition from remission to relapse may be abrupt and with few or no early warning signs; once illness recurrence occurs symptoms rapidly return to levels similar to the initial psychotic episode; while most patients respond promptly to re-introduction of antipsychotic treatment after relapse, the response time is variable and notably, treatment failure appears to emerge in about 1 in 6 patients. These observations are consistent with contemporary thinking on the dopamine hypothesis, including the aberrant salience hypothesis. Given the difficulties in identifying those at risk of relapse, the ineffectiveness of rescue medications in preventing full-blown psychotic recurrence and the potentially serious consequences, adherence and other factors predisposing to relapse should be a major focus of attention in managing schizophrenia. The place of antipsychotic treatment discontinuation in clinical practice and in placebo-controlled clinical trials needs to be carefully reconsidered.
Further clarification of factors predicting the outcome in schizophrenia is needed. The present review examines recent research into some of these predictors, focusing on insight, duration of untreated psychosis, cognition and early treatment response. It also addresses the need for standard outcome measures. There is good evidence that poor insight predicts poor outcome, although perhaps not simply as a consequence of poor compliance. Further support is provided for a link between duration of untreated psychosis and long-term outcome. The relationship between cognition and outcome is complex, with specific cognitive deficits apparently predicting particular outcome domains. Early treatment response is closely related to long-term outcome. Outcome studies may be flawed by sample selection bias, and a lack of standardized outcome measures. Several predictors are potentially modifiable, indicating that they should be targets for therapeutic intervention. More carefully designed studies are needed. Recently proposed criteria for remission are helpful, and should facilitate cross-sample comparisons.
Background: Childhood adversity is associated with cognitive impairments in schizophrenia. However, findings to date are inconsistent and little is known about the relationship between social cognition and childhood trauma. We investigated the relationship between childhood abuse and neglect and cognitive function in patients with a first-episode of schizophrenia or schizophreniform disorder (n = 56) and matched healthy controls (n = 52). To the best of our knowledge, this is the first study assessing this relationship in patients and controls exposed to similarly high levels of trauma.Methods: Pearson correlational coefficients were used to assess correlations between Childhood Trauma Questionnaire abuse and neglect scores and cognition. For the MCCB domains displaying significant (p < 0.05) correlations, within group hierarchical linear regression, was done to assess whether abuse and neglect were significant predictors of cognition after controlling for the effect of education.Results: Patients and controls reported similarly high levels of abuse and neglect. Cognitive performance was poorer for patients compared with controls for all cognitive domains except working memory and social cognition. After controlling for education, exposure to childhood neglect remained a significant predictor of impairment in social cognition in both patients and controls. Neglect was also a significant predictor of poorer verbal learning in patients and of attention/vigilance in controls. However, childhood abuse did not significantly predict cognitive impairments in either patients or controls.Conclusion: These findings are cross sectional and do not infer causality. Nonetheless, they indicate that associations between one type of childhood adversity (i.e. neglect) and social cognition are present and are not illness-specific.
Schizophrenia is a neuropsychiatric disorder characterized by dissociation of thoughts, idea, identity, and emotions. It has no central pathophysiological mechanism and precise diagnostic markers. Despite its high heritability, there are also environmental factors implicated in the development of schizophrenia. Epigenetic factors are thought to mediate the effects of environmental factors in the development of the disorder. Epigenetic modifications like DNA methylation are a risk factor for schizophrenia. Targeted gene approach studies attempted to find candidate gene methylation, but the results are contradictory. Genome-wide methylation studies are insufficient in literature and the available data do not cover different populations like the African populations. The current genome-wide studies have limitations related to the sample and methods used. Studies are required to control for these limitations. Integration of DNA methylation, gene expression, and their effects are important in the understanding of the development of schizophrenia and search for biomarkers. There are currently no precise and functional biomarkers for the disorder. Several epigenetic markers have been reported to be common in functional and peripheral tissue. This makes the peripheral tissue epigenetic changes a surrogate of functional tissue, suggesting common epigenetic alteration can be used as biomarkers of schizophrenia in peripheral tissue.