Brain structure and the relationship with neurocognitive functioning in schizophrenia and bipolar disorder : MRI studies

Brain structural abnormalities as well as neurocognitive dysfunction, are found in schizophrenia and in bipolar disorder. Based on the fact that both brain structure and neurocognitive functioning are significantly heritable and affected in both schizophrenia and bipolar disorder, relationships between them are expected. However, previous studies report inconsistent findings. Also, schizophrenia and bipolar disorder are classified as separate disease entities, but demonstrate overlap with regard to symptomatology and genetic liability. Few studies have directly compared brain structure abnormalities or relationships between brain structure and neurocognitive functioning between the diseases and, it remains unclear if findings are similar or different between patients with schizophrenia or bipolar disorder. The aims of the thesis were 1) to characterize brain structure and the relationships with neurocognitive performance in schizophrenia and bipolar disorder and healthy control subjects and, 2) to investigate these characteristics for differences and similarities between the subject groups. Two independent subject samples from two similar ongoing research projects at Karolinska Institutet in Sweden (HUBIN) and at the University of Oslo in Norway (TOP), were included. The participants were patients with schizophrenia or bipolar disorder, and healthy control subjects. All subjects were characterized using magnetic resonance imaging (MRI) of the brain and neuropsychological test methods. Brain cortical thickness and surface area measurements, as well as subcortical structure volumes were obtained using automated computer image analysis methods. Schizophrenia and bipolar disorder type 1 patients demonstrated cortical thinning in overlapping prefrontal and temporo-parietal brain regions compared with healthy controls, and schizophrenia and bipolar disorder patients demonstrated similar findings of subcortical volume abnormalities, compared to healthy controls. The identified abnormalities were more pronounced among schizophrenia patients. Cortical thickness and surface area in predominantly frontal and temporal regions, but also occipital regions, and several of the subcortical structure volumes, were related to neurocognitive performance in both patients and healthy controls. Between-group comparisons showed that some structure/function relationships were specific to schizophrenia and/or bipolar disorder. In conclusion, the results demonstrate numerous similar brain structure abnormalities in schizophrenia and bipolar disorder, consistent with a common underlying pathophysiology. Mostly similar brain structure/function relationships were found between patients and controls. Few relationships were found to be similar in schizophrenia and bipolar disorder, but different from healthy controls. Consequently, our findings do not indicate that the neurocognitive dysfunction found in both schizophrenia and bipolar disorder have common brain structural correlates. Some disease-specific relationships were found between brain structure and neurocognition, possibly reflecting disruptions in brain regions that contribute to specific cognitive functions and, could be of relevance to the pathophysiology in schizophrenia and bipolar disorder

Quality of clinical management of cardiometabolic risk factors in patients with severe mental illness in a specialist mental health care setting

Purpose Cardiometabolic disease in patients with severe mental illness is a major cause of shortened life expectancy. There is sparse evidence of real-world clinical risk prevention practice. We investigated levels of assessments of cardiometabolic risk factors and risk management interventions in patients with severe mental illness in the Norwegian mental health service according to an acknowledged international standard. Methods We collected data from 264 patients residing in six country-wide health trusts for: (a) assessments of cardiometabolic risk and (b) assessments of levels of risk reducing interventions. Logistic regressions were employed to investigate associations between risk and interventions. Results Complete assessments of all cardiometabolic risk variables were performed in 50% of the participants and 88% thereof had risk levels requiring intervention according to the standard. Smoking cessation advice was provided to 45% of daily smokers and 4% were referred to an intervention program. Obesity was identified in 62% and was associated with lifestyle interventions. Reassessment of psychotropic medication was done in 28% of the obese patients. Women with obesity were less likely to receive dietary advice, and use of clozapine or olanzapine reduced the chances for patients with obesity of getting weight reducing interventions. Conclusions Nearly nine out of the ten participants were identified as being at cardiometabolic high risk and only half of the participants were adequately screened. Women with obesity and patients using antipsychotics with higher levels of cardiometabolic side effects had fewer adequate interventions. The findings underscore the need for standardized recommendations for identification and provision of cardiometabolic risk reducing interventions in all patients with severe mental illness.publishedVersio

Impaired verbal learning is associated with larger caudate volumes in early onset schizophrenia spectrum disorders

Background Both brain structural abnormalities and neurocognitive impairments are core features of schizophrenia. We have previously reported enlargements in subcortical brain structure volumes and impairment of neurocognitive functioning as measured by the MATRICS Cognitive Consensus Battery (MCCB) in early onset schizophrenia spectrum disorders (EOS). To our knowledge, no previous study has investigated whether neurocognitive performance and volumetric abnormalities in subcortical brain structures are related in EOS. Methods Twenty-four patients with EOS and 33 healthy controls (HC) were included in the study. Relationships between the caudate nucleus, the lateral and fourth ventricles volumes and neurocognitive performance were investigated with multivariate linear regression analyses. Intracranial volume, age, antipsychotic medication and IQ were included as independent predictor-variables. Results The caudate volume was negatively correlated with verbal learning performance uniquely in the EOS group (r=-.454, p=.034). There were comparable positive correlations between the lateral ventricular volume and the processing speed, attention and reasoning and problem solving domains for both the EOS patients and the healthy controls. Antipsychotic medication was related to ventricular enlargements, but did not affect the brain structure-function relationship. Conclusion Enlargement of the caudate volume was related to poorer verbal learning performance in patients with EOS. Despite a 32% enlargement of the lateral ventricles in the EOS group, associations to processing speed, attention and reasoning and problem solving were similar for both the EOS and the HC groups

Cerebral cortical thickness and a history of obstetric complications in schizophrenia

Introduction: Magnetic resonance imaging (MRI) studies have demonstrated that patients with schizophrenia have thinner brain cortices compared with healthy control subjects. Neurodevelopment is vulnerable to obstetric complications (OCs) such as hypoxia and birth trauma, factors that are also related to increased risk of developing schizophrenia. With the hypothesis that OCs might explain the thinner cortices found in schizophrenia, we studied patients with schizophrenia and healthy controls subjects for association between number and severity of OCs and variation in cortical thickness. Methods: MRI scans of 54 adults with schizophrenia or schizoaffective disorder and 54 healthy controls were acquired at Karolinska Institutet, Stockholm, Sweden. Measures of brain cortical thickness were obtained using automated computer processing (FreeSurfer). OCs were assessed from obstetric records and scored blindly according to the McNeil-Sjostrom scale. At numerous cortical locations, putative effects of OCs on cortical thickness variation were tested for each trimester, for labour, for composite OC scores, severe OC scores, and hypoxia scores among patients and controls separately. Results: Number and severity of OCs varied among both patient and control subjects but were not associated with cortical thickness in either of the groups. Patients demonstrated thinner brain cortices but there were no significant differences in number and severity of OC scores across groups. Conclusion: In the present study, number and severity of obstetric complications were not associated with brain cortical thickness, in patients with schizophrenia or in healthy control subjects. The thinner brain cortices found in patients with schizophrenia were not explained by a history of OCs. (C) 2009 Elsevier Ltd. All rights reserved

Impaired verbal learning is associated with larger caudate volumes in early onset schizophrenia spectrum disorders

Background: Both brain structural abnormalities and neurocognitive impairments are core features of schizophrenia. We have previously reported enlargements in subcortical brain structure volumes and impairment of neurocognitive functioning as measured by the MATRICS Cognitive Consensus Battery (MCCB) in early onset schizophrenia spectrum disorders (EOS). To our knowledge, no previous study has investigated whether neurocognitive performance and volumetric abnormalities in subcortical brain structures are related in EOS. Methods: Twenty-four patients with EOS and 33 healthy controls (HC) were included in the study. Relationships between the caudate nucleus, the lateral and fourth ventricles volumes and neurocognitive performance were investigated with multivariate linear regression analyses. Intracranial volume, age, antipsychotic medication and IQ were included as independent predictor-variables. Results: The caudate volume was negatively correlated with verbal learning performance uniquely in the EOS group (r=-.454, p = .034). There were comparable positive correlations between the lateral ventricular volume and the processing speed, attention and reasoning and problem solving domains for both the EOS patients and the healthy controls. Antipsychotic medication was related to ventricular enlargements, but did not affect the brain structure-function relationship. Conclusion: Enlargement of the caudate volume was related to poorer verbal learning performance in patients with EOS. Despite a 32% enlargement of the lateral ventricles in the EOS group, associations to processing speed, attention and reasoning and problem solving were similar for both the EOS and the HC groups

Quality of clinical management of cardiometabolic risk factors in patients with severe mental illness in a specialist mental health care setting

Purpose Cardiometabolic disease in patients with severe mental illness is a major cause of shortened life expectancy. There is sparse evidence of real-world clinical risk prevention practice. We investigated levels of assessments of cardiometabolic risk factors and risk management interventions in patients with severe mental illness in the Norwegian mental health service according to an acknowledged international standard. Methods We collected data from 264 patients residing in six country-wide health trusts for: (a) assessments of cardiometabolic risk and (b) assessments of levels of risk reducing interventions. Logistic regressions were employed to investigate associations between risk and interventions. Results Complete assessments of all cardiometabolic risk variables were performed in 50% of the participants and 88% thereof had risk levels requiring intervention according to the standard. Smoking cessation advice was provided to 45% of daily smokers and 4% were referred to an intervention program. Obesity was identified in 62% and was associated with lifestyle interventions. Reassessment of psychotropic medication was done in 28% of the obese patients. Women with obesity were less likely to receive dietary advice, and use of clozapine or olanzapine reduced the chances for patients with obesity of getting weight reducing interventions. Conclusions Nearly nine out of the ten participants were identified as being at cardiometabolic high risk and only half of the participants were adequately screened. Women with obesity and patients using antipsychotics with higher levels of cardiometabolic side effects had fewer adequate interventions. The findings underscore the need for standardized recommendations for identification and provision of cardiometabolic risk reducing interventions in all patients with severe mental illness

Quality of clinical management of cardiometabolic risk factors in patients with severe mental illness in a specialist mental health care setting

Purpose: Cardiometabolic disease in patients with severe mental illness is a major cause of shortened life expectancy. There is sparse evidence of real-world clinical risk prevention practice. We investigated levels of assessments of cardiometabolic risk factors and risk management interventions in patients with severe mental illness in the Norwegian mental health service according to an acknowledged international standard. Methods: We collected data from 264 patients residing in six country-wide health trusts for: (a) assessments of cardiometabolic risk and (b) assessments of levels of risk reducing interventions. Logistic regressions were employed to investigate associations between risk and interventions. Results: Complete assessments of all cardiometabolic risk variables were performed in 50% of the participants and 88% thereof had risk levels requiring intervention according to the standard. Smoking cessation advice was provided to 45% of daily smokers and 4% were referred to an intervention program. Obesity was identified in 62% and was associated with lifestyle interventions. Reassessment of psychotropic medication was done in 28% of the obese patients. Women with obesity were less likely to receive dietary advice, and use of clozapine or olanzapine reduced the chances for patients with obesity of getting weight reducing interventions. Conclusions: Nearly nine out of the ten participants were identified as being at cardiometabolic high risk and only half of the participants were adequately screened. Women with obesity and patients using antipsychotics with higher levels of cardiometabolic side effects had fewer adequate interventions. The findings underscore the need for standardized recommendations for identification and provision of cardiometabolic risk reducing interventions in all patients with severe mental illness