Schizophrenia bulletin
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Schizophrenia bulletin · Sep 2015
Multicenter StudyPatterns of Gray Matter Abnormalities in Schizophrenia Based on an International Mega-analysis.
Analyses of gray matter concentration (GMC) deficits in patients with schizophrenia (Sz) have identified robust changes throughout the cortex. We assessed the relationships between diagnosis, overall symptom severity, and patterns of gray matter in the largest aggregated structural imaging dataset to date. We performed both source-based morphometry (SBM) and voxel-based morphometry (VBM) analyses on GMC images from 784 Sz and 936 controls (Ct) across 23 scanning sites in Europe and the United States. ⋯ We found no significant association between the component loadings and symptom severity in either analysis. This mega-analysis confirms that the commonly found GMC loss in Sz in the anterior temporal lobe, insula, and medial frontal lobe form a single, consistent spatial pattern even in such a diverse dataset. The separation of GMC loss into robust, repeatable spatial patterns across multiple datasets paves the way for the application of these methods to identify subtle genetic and clinical cohort effects.
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Schizophrenia bulletin · Sep 2013
Randomized Controlled Trial Multicenter StudyEffects of risperidone and olanzapine dose reduction on cognitive function in stable patients with schizophrenia: an open-label, randomized, controlled, pilot study.
Impact of dose reduction of atypical antipsychotics on cognitive function has not been investigated in stable patients with schizophrenia. In this open-label, 28-week, randomized controlled trial, stable patients with schizophrenia treated with risperidone or olanzapine were randomly assigned to the reduction group (dose reduced by 50% in 4 weeks and then maintained) or maintenance group (dose kept constant). Assessments at baseline and week 28 included the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), Positive and Negative Syndrome Scale (PANSS), and Drug-Induced Extrapyramidal Symptoms Scale (DIEPSS). ⋯ This 6-month pilot study suggests that risperidone or olanzapine dose reduction of 50% can improve cognitive function for stable patients with schizophrenia. Due to the open-label design, small sample size, and short study duration, however, there is a need to confirm the finding through double-blind, larger scale trials with longer follow-up periods. Moreover, potential risks of relapse following antipsychotic dose reduction should be thoroughly investigated in longer term studies.
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Schizophrenia bulletin · May 2013
Randomized Controlled Trial Multicenter StudyDopamine D2 receptor occupancy and cognition in schizophrenia: analysis of the CATIE data.
Antipsychotic drugs exert antipsychotic effects by blocking dopamine D2 receptors in the treatment of schizophrenia. However, effects of D2 receptor blockade on neurocognitive function still remain to be elucidated. The objective of this analysis was to evaluate impacts of estimated dopamine D2 receptor occupancy with antipsychotic drugs on several domains of neurocognitive function in patients with schizophrenia in the Clinical Antipsychotic Trials in Intervention Effectiveness (CATIE) trial. ⋯ These findings suggest a nonlinear relationship between prescribed antipsychotic doses and overall neurocognitive function and vigilance. This study shows that D2 occupancy above approximately 80% not only increases the risk for extrapyramidal side effects as consistently reported in the literature but also increases the risk for cognitive impairment.
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Schizophrenia bulletin · Oct 2006
Randomized Controlled Trial Multicenter Study Comparative StudyConduct disorder and antisocial personality disorder in persons with severe psychiatric and substance use disorders.
Conduct disorder (CD) and antisocial personality disorder (ASPD) are established risk factors for substance use disorders in both the general population and among persons with schizophrenia and other severe mental illnesses. Among clients with substance use disorders in the general population, CD and ASPD are associated with more severe problems and criminal justice involvement, but little research has examined their correlates in clients with dual disorders. ⋯ However, clients with Full ASPD had the most criminal justice involvement, especially with respect to violent charges and convictions. The results suggest that a late-onset ASPD subtype may develop in clients with severe mental illness secondary to substance abuse, but that much criminal behavior in clients with dual disorders may be due to the early onset of the full ASPD syndrome in this population and not the effects of substance use disorders.
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Schizophrenia bulletin · Jan 2004
Multicenter Study Clinical TrialEffectiveness of atypical antipsychotic medications in reducing violent behavior among persons with schizophrenia in community-based treatment.
This study prospectively compared the effectiveness of atypical antipsychotic medications to that of conventional neuroleptics in reducing violent behavior among patients with schizophrenia under "usual care" conditions in the community. Participants (n = 229) were adults with schizophrenia spectrum disorders receiving inpatient or outpatient services in public sector mental health systems in North Carolina. Subjects were followed for 2 years in an observational study using multiple methods of data collection at 6-month intervals to assess treatment, sociodemographic characteristics, clinical features, and violence outcomes. ⋯ A cumulative effect on reduced violence was attributable to consistent compliance with atypical antipsychotic medications over a 2-year period. Concurrent reductions in psychotic symptoms, substance abuse, and adverse medication side effects were found to mediate the association between adherence with atypicals and lower violence risk. Treatment with atypical antipsychotic medications should be considered as an important component of violence risk management for schizophrenia patients at risk for violent behavior.