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1.
BJPsych Open ; 9(4): e128, 2023 Jul 17.
Article in English | MEDLINE | ID: mdl-37458249

ABSTRACT

BACKGROUND: There are few data on the profile of those with serious mental illness (SMI) admitted to hospital for physical health reasons. AIMS: To compare outcomes for patients with and without an SMI admitted to hospital in England where the primary reason for admission was chronic obstructive pulmonary disease (COPD). METHOD: This was a retrospective, observational analysis of the English Hospital Episodes Statistics data-set for the period from 1 April 2018 to 31 March 2019, for patients aged 18-74 years with COPD as the dominant reason for admission. Patient with an SMI (psychosis spectrum disorder, bipolar disorder) were identified. RESULTS: Data were available for 54 578 patients, of whom 2096 (3.8%) had an SMI. Patients with an SMI were younger, more likely to be female and more likely to live in deprived areas than those without an SMI. The burden of comorbidity was similar between the two groups. After adjusting for covariates, SMI was associated with significantly greater risk of length of stay than the median (odds ratio 1.24, 95% CI 1.12-1.37, P ≤ 0.001) and with 30-day emergency readmission (odds ratio 1.51, 95% confidence interval 1.34-1.69, P ≤ 0.001) but not with in-hospital mortality. CONCLUSION: Clinicians should be aware of the potential for poorer outcomes in patients with an SMI even when the SMI is not the primary reason for admission. Collaborative working across mental and physical healthcare provision may facilitate improved outcomes for people with SMI.

2.
J Psychiatr Res ; 121: 62-67, 2020 02.
Article in English | MEDLINE | ID: mdl-31770658

ABSTRACT

Schizophrenia (SZ) and bipolar disorder (BD) are highly heritable, share symptomatology, and have a polygenic architecture. The impact of recent polygenic risk scores (PRS) for psychosis, which combine multiple genome-wide associated risk variations, should be assessed on heritable brain phenotypes also previously associated with the illnesses, for a better understanding of the pathways to disease. We have recently reported on the current SZ PRS's ability to predict 1st episode of psychosis case-control status and general cognition. Herein, we test its penetrance on white matter microstructure, which is known to be impaired in SZ, in BD and their relatives, using 141 participants (including SZ, BP, relatives of SZ or BP patients, and healthy volunteers), and two white matter integrity indexes: fractional anisotropy (FA) and mean diffusivity (MD). No significant correlation between the SZ PRS and FA or MD was found, thus it remains unclear whether white matter changes are primarily associated with SZ genetic risk profiles.


Subject(s)
Bipolar Disorder/genetics , Bipolar Disorder/pathology , Schizophrenia/genetics , Schizophrenia/pathology , White Matter/pathology , Adult , Bipolar Disorder/diagnostic imaging , Diffusion Tensor Imaging , Family , Genetic Predisposition to Disease , Genome-Wide Association Study , Humans , Multifactorial Inheritance , Schizophrenia/diagnostic imaging , White Matter/diagnostic imaging
3.
Br J Psychiatry ; 214(2): 63-73, 2019 02.
Article in English | MEDLINE | ID: mdl-30251622

ABSTRACT

BACKGROUND: Obesity is a major challenge for people with schizophrenia.AimsWe assessed whether STEPWISE, a theory-based, group structured lifestyle education programme could support weight reduction in people with schizophrenia. METHOD: In this randomised controlled trial (study registration: ISRCTN19447796), we recruited adults with schizophrenia, schizoaffective disorder or first-episode psychosis from ten mental health organisations in England. Participants were randomly allocated to the STEPWISE intervention or treatment as usual. The 12-month intervention comprised four 2.5 h weekly group sessions, followed by 2-weekly maintenance contact and group sessions at 4, 7 and 10 months. The primary outcome was weight change after 12 months. Key secondary outcomes included diet, physical activity, biomedical measures and patient-related outcome measures. Cost-effectiveness was assessed and a mixed-methods process evaluation was included. RESULTS: Between 10 March 2015 and 31 March 2016, we recruited 414 people (intervention 208, usual care 206) with 341 (84.4%) participants completing the trial. At 12 months, weight reduction did not differ between groups (mean difference 0.0 kg, 95% CI -1.6 to 1.7, P = 0.963); physical activity, dietary intake and biochemical measures were unchanged. STEPWISE was well-received by participants and facilitators. The healthcare perspective incremental cost-effectiveness ratio was £246 921 per quality-adjusted life-year gained. CONCLUSIONS: Participants were successfully recruited and retained, indicating a strong interest in weight interventions; however, the STEPWISE intervention was neither clinically nor cost-effective. Further research is needed to determine how to manage overweight and obesity in people with schizophrenia.Declaration of interestR.I.G.H. received fees for lecturing, consultancy work and attendance at conferences from the following: Boehringer Ingelheim, Eli Lilly, Janssen, Lundbeck, Novo Nordisk, Novartis, Otsuka, Sanofi, Sunovion, Takeda, MSD. M.J.D. reports personal fees from Novo Nordisk, Sanofi-Aventis, Lilly, Merck Sharp & Dohme, Boehringer Ingelheim, AstraZeneca, Janssen, Servier, Mitsubishi Tanabe Pharma Corporation, Takeda Pharmaceuticals International Inc.; and, grants from Novo Nordisk, Sanofi-Aventis, Lilly, Boehringer Ingelheim, Janssen. K.K. has received fees for consultancy and speaker for Novartis, Novo Nordisk, Sanofi-Aventis, Lilly, Servier and Merck Sharp & Dohme. He has received grants in support of investigator and investigator-initiated trials from Novartis, Novo Nordisk, Sanofi-Aventis, Lilly, Pfizer, Boehringer Ingelheim and Merck Sharp & Dohme. K.K. has received funds for research, honoraria for speaking at meetings and has served on advisory boards for Lilly, Sanofi-Aventis, Merck Sharp & Dohme and Novo Nordisk. D.Sh. is expert advisor to the NICE Centre for guidelines; board member of the National Collaborating Centre for Mental Health (NCCMH); clinical advisor (paid consultancy basis) to National Clinical Audit of Psychosis (NCAP); views are personal and not those of NICE, NCCMH or NCAP. J.P. received personal fees for involvement in the study from a National Institute for Health Research (NIHR) grant. M.E.C. and Y.D. report grants from NIHR Health Technology Assessment, during the conduct of the study; and The Leicester Diabetes Centre, an organisation (employer) jointly hosted by an NHS Hospital Trust and the University of Leicester and who is holder (through the University of Leicester) of the copyright of the STEPWISE programme and of the DESMOND suite of programmes, training and intervention fidelity framework that were used in this study. S.R. has received honorarium from Lundbeck for lecturing. F.G. reports personal fees from Otsuka and Lundbeck, personal fees and non-financial support from Sunovion, outside the submitted work; and has a family member with professional links to Lilly and GSK, including shares. F.G. is in part funded by the National Institute for Health Research Collaboration for Leadership in Applied Health Research & Care Funding scheme, by the Maudsley Charity and by the Stanley Medical Research Institute and is supported by the by the Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King's College London.


Subject(s)
Obesity/therapy , Patient Education as Topic/methods , Psychotic Disorders/therapy , Schizophrenia/therapy , Adult , Biomarkers/blood , Cost-Benefit Analysis , Eating/psychology , Exercise , Female , Humans , Life Style , Male , Obesity/blood , Obesity/complications , Psychotherapy, Group , Psychotic Disorders/blood , Psychotic Disorders/complications , Schizophrenia/blood , Schizophrenia/complications , Weight Loss
4.
Genes Brain Behav ; 18(4): e12510, 2019 04.
Article in English | MEDLINE | ID: mdl-30079586

ABSTRACT

CACNA1C-rs1006737 and ZNF804A-rs1344706 polymorphisms are among the most robustly associated with schizophrenia (SCZ) and bipolar disorder (BD), and recently with brain phenotypes. As these patients show abnormal verbal fluency (VF) and related brain activation, we asked whether the latter was affected by these polymorphisms (alone and in interaction)-to better understand how they might induce risk. We recently reported effects on functional VF-related (for ZNF804A-rs1344706) and structural (for both) connectivity. We genotyped and fMRI-scanned 54 SCZ, 40 BD and 80 controls during VF. With SPM, we assessed the main effect of CACNA1C-rs1006737, and its interaction with ZNF804A-rs1344706, and their interaction with diagnosis, on regional brain activation and functional connectivity (psychophysiological interactions-PPI). Using public data, we reported effects of CACNA1C-rs1006737 and diagnosis on brain expression. The CACNA1C-rs1006737 risk allele was associated with increased activation, particularly in the bilateral prefronto-temporal cortex and thalamus; decreased PPI, especially in the left temporal cortex; and gene expression in white matter and the cerebellum. We also found unprecedented evidence for epistasis (interaction between genetic polymorphisms) in the caudate nucleus, thalamus, and cingulate and temporal cortical activation; and CACNA1C up-regulation in SCZ and BD parietal cortices. Some effects were dependent on BD/SCZ diagnosis. All imaging results were whole-brain, voxel-wise, and familywise-error corrected. Our results support evidence implicating CACNA1C and ZNF804A in BD and SCZ, adding novel imaging evidence in clinical populations, and of epistasis-which needs further replication. Further scrutiny of the inherent neurobiological mechanisms may disclose their potential as putative drug targets.


Subject(s)
Bipolar Disorder/genetics , Brain/physiopathology , Calcium Channels, L-Type/genetics , Epistasis, Genetic , Kruppel-Like Transcription Factors/genetics , Polymorphism, Single Nucleotide , Schizophrenia/genetics , Adult , Brain/diagnostic imaging , Brain/metabolism , Connectome , Humans , Male , Middle Aged
5.
Health Technol Assess ; 22(65): 1-160, 2018 11.
Article in English | MEDLINE | ID: mdl-30499443

ABSTRACT

BACKGROUND: Obesity is twice as common in people with schizophrenia as in the general population. The National Institute for Health and Care Excellence guidance recommends that people with psychosis or schizophrenia, especially those taking antipsychotics, be offered a healthy eating and physical activity programme by their mental health care provider. There is insufficient evidence to inform how these lifestyle services should be commissioned. OBJECTIVES: To develop a lifestyle intervention for people with first episode psychosis or schizophrenia and to evaluate its clinical effectiveness, cost-effectiveness, delivery and acceptability. DESIGN: A two-arm, analyst-blind, parallel-group, randomised controlled trial, with a 1 : 1 allocation ratio, using web-based randomisation; a mixed-methods process evaluation, including qualitative case study methods and logic modelling; and a cost-utility analysis. SETTING: Ten community mental health trusts in England. PARTICIPANTS: People with first episode psychosis, schizophrenia or schizoaffective disorder. INTERVENTIONS: Intervention group: (1) four 2.5-hour group-based structured lifestyle self-management education sessions, 1 week apart; (2) multimodal fortnightly support contacts; (3) three 2.5-hour group booster sessions at 3-monthly intervals, post core sessions. Control group: usual care assessed through a longitudinal survey. All participants received standard written lifestyle information. MAIN OUTCOME MEASURES: The primary outcome was change in weight (kg) at 12 months post randomisation. The key secondary outcomes measured at 3 and 12 months included self-reported nutrition (measured with the Dietary Instrument for Nutrition Education questionnaire), objectively measured physical activity measured by accelerometry [GENEActiv (Activinsights, Kimbolton, UK)], biomedical measures, adverse events, patient-reported outcome measures and a health economic assessment. RESULTS: The trial recruited 414 participants (intervention arm: 208 participants; usual care: 206 participants) between 10 March 2015 and 31 March 2016. A total of 341 participants (81.6%) completed the trial. A total of 412 participants were analysed. After 12 months, weight change did not differ between the groups (mean difference 0.0 kg, 95% confidence interval -1.59 to 1.67 kg; p = 0.964); physical activity, dietary intake and biochemical measures were unchanged. Glycated haemoglobin, fasting glucose and lipid profile were unchanged by the intervention. Quality of life, psychiatric symptoms and illness perception did not change during the trial. There were three deaths, but none was related to the intervention. Most adverse events were expected and related to the psychiatric illness. The process evaluation showed that the intervention was acceptable, with participants valuing the opportunity to interact with others facing similar challenges. Session feedback indicated that 87.2% of participants agreed that the sessions had met their needs. Some indicated the desire for more ongoing support. Professionals felt that the intervention was under-resourced and questioned the long-term sustainability within current NHS settings. Professionals would have preferred greater access to participants' behaviour data to tailor the intervention better. The incremental cost-effectiveness ratio from the health-care perspective is £246,921 per quality-adjusted life-year (QALY) gained and the incremental cost-effectiveness ratio from the societal perspective is £367,543 per QALY gained. CONCLUSIONS: Despite the challenges of undertaking clinical research in this population, the trial successfully recruited and retained participants, indicating a high level of interest in weight management interventions; however, the STEPWISE intervention was neither clinically effective nor cost-effective. Further research will be required to define how overweight and obesity in people with schizophrenia should be managed. The trial results suggest that lifestyle programmes for people with schizophrenia may need greater resourcing than for other populations, and interventions that have been shown to be effective in other populations, such as people with diabetes mellitus, are not necessarily effective in people with schizophrenia. TRIAL REGISTRATION: Current Controlled Trials ISRCTN19447796. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 65. See the NIHR Journals Library website for further project information.


Subject(s)
Behavior Therapy , Life Style , Psychotic Disorders , Schizophrenia , Technology Assessment, Biomedical , Weight Loss/physiology , Adult , Cost-Benefit Analysis , Diet, Healthy , England/epidemiology , Exercise , Female , Humans , Male , Obesity/epidemiology , State Medicine
6.
Eur Neuropsychopharmacol ; 27(5): 494-503, 2017 05.
Article in English | MEDLINE | ID: mdl-28392151

ABSTRACT

Bipolar disorder (BPD) is associated with altered regional brain function during the performance of cognitive tasks. The relative contribution of genetic and environmental risk factors for BPD to these changes has not yet been quantified. We sought to address this issue in a functional neuroimaging study of people who varied in their risk for BPD. Functional magnetic resonance imaging was used to study 124 subjects (29 twin and 9 sibling pairs with at least one member with BPD, and 24 healthy twin pairs) performing a working memory task. We assessed the influence of risk for BPD on regional brain function during the task in a two stage process. Firstly, we identified areas where there were group differences in activation. Secondly, we estimated the heritability and phenotypic correlation of activation and BPD using genetic modeling. BPD was associated with increased activation in the anterior cingulate, orbitofrontal, medial prefrontal, and left precentral cortices, and in the precuneus. Within these regions, activation in the orbitofrontal cortex rendered the most significant heritability estimate (h2=0.40), and was significantly correlated with BPD phenotype (rph=0.29). A moderate proportion of the genetic influences (rg=0.69) acting on both BPD and on the degree of orbitofrontal activation were shared. These findings suggest that genetic factors that confer vulnerability to BPD alter brain function in BPD.


Subject(s)
Bipolar Disorder/genetics , Bipolar Disorder/pathology , Brain/pathology , Diseases in Twins , Family Health , Adult , Bipolar Disorder/diagnostic imaging , Brain/diagnostic imaging , Female , Gene-Environment Interaction , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Middle Aged , Oxygen/blood , Psychiatric Status Rating Scales , Risk Factors , Twins/genetics , Twins, Dizygotic , Twins, Monozygotic
7.
Trials ; 17(1): 475, 2016 Sep 29.
Article in English | MEDLINE | ID: mdl-27681572

ABSTRACT

BACKGROUND: People with schizophrenia are two to three times more likely to be overweight than the general population. The UK National Institute of Health and Care Excellence (NICE) recommends an annual physical health review with signposting to, or provision of, a lifestyle programme to address weight concerns and obesity. The purpose of this randomised controlled trial is to assess whether a group-based structured education programme can help people with schizophrenia to lose weight. METHODS: Design: a randomised controlled trial of a group-based structured education programme. SETTING: 10 UK community mental health trusts. PARTICIPANTS: 396 adults with schizophrenia, schizoaffective, or first-episode psychosis who are prescribed antipsychotic medication will be recruited. Participants will be overweight, obese or be concerned about their weight. INTERVENTION: participants will be randomised to either the intervention or treatment as usual (TAU). The intervention arm will receive TAU plus four 2.5-h weekly sessions of theory-based lifestyle structured group education, with maintenance contact every 2 weeks and 'booster' sessions every 3 months. All participants will receive standardised written information about healthy eating, physical activity, alcohol and smoking. OUTCOMES: the primary outcome is weight (kg) change at 1 year post randomisation. Secondary outcomes, which will be assessed at 3 and 12 months, include: the proportion of participants who maintained or reduced their weight; waist circumference; body mass index; objectively measured physical activity (wrist accelerometer); self-reported diet; blood pressure; fasting plasma glucose, lipid profile and HbA1c (baseline and 1 year only); health-related quality of life (EQ-5D-5L and RAND SF-36); (adapted) brief illness perception questionnaire; the Brief Psychiatric Rating Scale; the Client Service Receipt Inventory; medication use; smoking status; adverse events; depression symptoms (Patient Health Questionnaire-9); use of weight-loss programmes; and session feedback (intervention only). Outcome assessors will be blind to trial group allocation. Qualitative interviews with a subsample of facilitators and invention-arm participants will provide data on intervention feasibility and acceptability. Assessment of intervention fidelity will also be performed. DISCUSSION: The STEPWISE trial will provide evidence for the clinical and cost-effectiveness of a tailored intervention, which, if successful, could be implemented rapidly in the NHS. TRIAL REGISTRATION: ISRCTN19447796 , registered on 20 March 2014.

8.
BJPsych Bull ; 40(3): 156-61, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27280038

ABSTRACT

This paper describes the need for commissioners and service providers to consider the development of a whole-system approach to providing rehabilitation services for patients with complex psychosis, in the context of the current economic pressures and emergence of a competitive market in this area of mental health. The practical and organisational arrangements for the management of risk with such services are described, taking into account the varying provision of rehabilitation services across the UK and considering how these can be developed against the care clustering system and interfaces with other mental health services.

9.
Br J Psychiatry ; 208(6): 539-47, 2016 06.
Article in English | MEDLINE | ID: mdl-26989096

ABSTRACT

BACKGROUND: Twin studies have lacked statistical power to apply advanced genetic modelling techniques to the search for cognitive endophenotypes for bipolar disorder. AIMS: To quantify the shared genetic variability between bipolar disorder and cognitive measures. METHOD: Structural equation modelling was performed on cognitive data collected from 331 twins/siblings of varying genetic relatedness, disease status and concordance for bipolar disorder. RESULTS: Using a parsimonious AE model, verbal episodic and spatial working memory showed statistically significant genetic correlations with bipolar disorder (rg = |0.23|-|0.27|), which lost statistical significance after covarying for affective symptoms. Using an ACE model, IQ and visual-spatial learning showed statistically significant genetic correlations with bipolar disorder (rg = |0.51|-|1.00|), which remained significant after covarying for affective symptoms. CONCLUSIONS: Verbal episodic and spatial working memory capture a modest fraction of the bipolar diathesis. IQ and visual-spatial learning may tap into genetic substrates of non-affective symptomatology in bipolar disorder.


Subject(s)
Bipolar Disorder/genetics , Cognitive Dysfunction/genetics , Endophenotypes , Memory Disorders/genetics , Memory, Episodic , Models, Genetic , Adolescent , Adult , Aged , Bipolar Disorder/physiopathology , Cognitive Dysfunction/physiopathology , Female , Humans , Male , Memory Disorders/physiopathology , Memory, Short-Term/physiology , Middle Aged , Siblings , Spatial Memory/physiology , Twins , Young Adult
10.
Soc Cogn Affect Neurosci ; 11(5): 746-57, 2016 05.
Article in English | MEDLINE | ID: mdl-26714573

ABSTRACT

Individual differences in cognitive ability and social behaviour are influenced by the variability in the structure and function of the limbic system. A strong heritability of the limbic cortex has been previously reported, but little is known about how genetic factors influence specific limbic networks. We used diffusion tensor imaging tractography to investigate heritability of different limbic tracts in 52 monozygotic and 34 dizygotic healthy adult twins. We explored the connections that contribute to the activity of three distinct functional limbic networks, namely the dorsal cingulum ('medial default-mode network'), the ventral cingulum and the fornix ('hippocampal-diencephalic-retrosplenial network') and the uncinate fasciculus ('temporo-amygdala-orbitofrontal network'). Genetic and environmental variances were mapped for multiple tract-specific measures that reflect different aspects of the underlying anatomy. We report the highest heritability for the uncinate fasciculus, a tract that underpins emotion processing, semantic cognition, and social behaviour. High to moderate genetic and shared environmental effects were found for pathways important for social behaviour and memory, for example, fornix, dorsal and ventral cingulum. These findings indicate that within the limbic system inheritance of specific traits may rely on the anatomy of distinct networks and is higher for fronto-temporal pathways dedicated to complex social behaviour and emotional processing.


Subject(s)
Cerebral Cortex/anatomy & histology , Diffusion Tensor Imaging/methods , Limbic System/anatomy & histology , Nerve Net/anatomy & histology , Registries , Twins/genetics , Adult , Female , Humans , Inheritance Patterns , Male , Middle Aged , Neural Pathways/anatomy & histology , Young Adult
11.
J Neurosci ; 35(37): 12625-34, 2015 Sep 16.
Article in English | MEDLINE | ID: mdl-26377454

ABSTRACT

Acquisition of language skills depends on the progressive maturation of specialized brain networks that are usually lateralized in adult population. However, how genetic and environmental factors relate to the age-related differences in lateralization of these language pathways is still not known. We recruited 101 healthy right-handed subjects aged 9-40 years to investigate age-related differences in the anatomy of perisylvian language pathways and 86 adult twins (52 monozygotic and 34 dizygotic) to understand how heritability factors influence language anatomy. Diffusion tractography was used to dissect and extract indirect volume measures from the three segments of the arcuate fasciculus connecting Wernicke's to Broca's region (i.e., long segment), Broca's to Geschwind's region (i.e., anterior segment), and Wernicke's to Geschwind's region (i.e., posterior segment). We found that the long and anterior arcuate segments are lateralized before adolescence and their lateralization remains stable throughout adolescence and early adulthood. Conversely, the posterior segment shows right lateralization in childhood but becomes progressively bilateral during adolescence, driven by a reduction in volume in the right hemisphere. Analysis of the twin sample showed that genetic and shared environmental factors influence the anatomy of those segments that lateralize earlier, whereas specific environmental effects drive the variability in the volume of the posterior segment that continues to change in adolescence and adulthood. Our results suggest that the age-related differences in the lateralization of the language perisylvian pathways are related to the relative contribution of genetic and environmental effects specific to each segment. SIGNIFICANCE STATEMENT: Our study shows that, by early childhood, frontotemporal (long segment) and frontoparietal (anterior segment) connections of the arcuate fasciculus are left and right lateralized, respectively, and remain lateralized throughout adolescence and early adulthood. In contrast, temporoparietal (posterior segment) connections are right lateralized in childhood, but become progressively bilateral during adolescence. Preliminary twin analysis suggested that lateralization of the arcuate fasciculus is a heterogeneous process that depends on the interplay between genetic and environment factors specific to each segment. Tracts that exhibit higher age effects later in life (i.e., posterior segment) appear to be influenced more by specific environmental factors.


Subject(s)
Aging/physiology , Cerebral Cortex/physiology , Gene-Environment Interaction , Language Development , Nerve Net/physiology , Adolescent , Adult , Axons/ultrastructure , Broca Area/physiology , Cerebral Cortex/ultrastructure , Child , Diffusion Tensor Imaging , Dominance, Cerebral/physiology , Female , Humans , Male , Models, Neurological , Organ Size , Quantitative Trait, Heritable , Twins, Dizygotic , Twins, Monozygotic , Wernicke Area/physiology , Young Adult
12.
Hum Brain Mapp ; 34(9): 2244-58, 2013 Sep.
Article in English | MEDLINE | ID: mdl-22438288

ABSTRACT

The genes for the dopamine transporter (DAT) and the D-Amino acid oxidase activator (DAOA or G72) have been independently implicated in the risk for schizophrenia and in bipolar disorder and/or their related intermediate phenotypes. DAT and G72 respectively modulate central dopamine and glutamate transmission, the two systems most robustly implicated in these disorders. Contemporary studies have demonstrated that elevated dopamine function is associated with glutamatergic dysfunction in psychotic disorders. Using functional magnetic resonance imaging we examined whether there was an interaction between the effects of genes that influence dopamine and glutamate transmission (DAT and G72) on regional brain activation during verbal fluency, which is known to be abnormal in psychosis, in 80 healthy volunteers. Significant interactions between the effects of G72 and DAT polymorphisms on activation were evident in the striatum, parahippocampal gyrus, and supramarginal/angular gyri bilaterally, the right insula, in the right pre-/postcentral and the left posterior cingulate/retrosplenial gyri (P < 0.05, FDR-corrected across the whole brain). This provides evidence that interactions between the dopamine and the glutamate system, thought to be altered in psychosis, have an impact in executive processing which can be modulated by common genetic variation.


Subject(s)
Brain Mapping , Brain/physiology , Carrier Proteins/genetics , Dopamine Plasma Membrane Transport Proteins/genetics , Epistasis, Genetic/physiology , Genetic Predisposition to Disease/genetics , Adult , Dopamine/genetics , Female , Genotype , Glutamic Acid/genetics , Healthy Volunteers , Humans , Image Processing, Computer-Assisted , Intracellular Signaling Peptides and Proteins , Magnetic Resonance Imaging , Male , Polymorphism, Single Nucleotide , Psychotic Disorders/genetics , Reverse Transcriptase Polymerase Chain Reaction , Schizophrenia/genetics , Synaptic Transmission/genetics , Verbal Learning
13.
Hum Brain Mapp ; 33(1): 143-53, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21391259

ABSTRACT

BACKGROUND: The D-Amino acid oxidase activator (G72 or DAOA) is believed to play a key role in the regulation of central glutamatergic transmission which is seen to be altered in psychosis. It is thought to regulate D-amino acid oxidase (DAO), which metabolizes D-serine, a co-agonist of NMDA-type glutamate receptors and to be involved in dendritic arborization. Linkage, genetic association and expression studies have implicated the G72 gene in both schizophrenia and bipolar disorder. AIMS: To examine the influence of G72 variation on brain function in the healthy population. METHOD: Fifty healthy volunteers were assessed using functional magnetic resonance imaging while performing a verbal fluency task. Regional brain activation and task-dependent functional connectivity during word generation was compared between different rs746187 genotypes. RESULTS: G72 rs746187 genotype had a significant effect on activation in the left postcentral and supramarginal gyri (FWE P < 0.05), and on the task-dependent functional coupling of this region with the retrosplenial cingulate gyrus (FWE P < 0.05). CONCLUSIONS: Our results may reflect an effect of G72 on glutamatergic transmission, mediated by an influence on D-amino acid oxidase activity, on brain areas particularly relevant to the hypoglutamatergic model of psychosis.


Subject(s)
Brain/physiology , Carrier Proteins/genetics , Glutamic Acid/metabolism , Polymorphism, Single Nucleotide , Verbal Behavior/physiology , Adult , Brain Mapping , Female , Genotype , Humans , Intracellular Signaling Peptides and Proteins , Magnetic Resonance Imaging , Male , Middle Aged , Nerve Net/physiology , Neuroimaging
14.
Hum Mol Genet ; 20(24): 4786-96, 2011 Dec 15.
Article in English | MEDLINE | ID: mdl-21908516

ABSTRACT

Studies of the major psychoses, schizophrenia (SZ) and bipolar disorder (BD), have traditionally focused on genetic and environmental risk factors, although more recent work has highlighted an additional role for epigenetic processes in mediating susceptibility. Since monozygotic (MZ) twins share a common DNA sequence, their study represents an ideal design for investigating the contribution of epigenetic factors to disease etiology. We performed a genome-wide analysis of DNA methylation on peripheral blood DNA samples obtained from a unique sample of MZ twin pairs discordant for major psychosis. Numerous loci demonstrated disease-associated DNA methylation differences between twins discordant for SZ and BD individually, and together as a combined major psychosis group. Pathway analysis of our top loci highlighted a significant enrichment of epigenetic changes in biological networks and pathways directly relevant to psychiatric disorder and neurodevelopment. The top psychosis-associated, differentially methylated region, significantly hypomethylated in affected twins, was located in the promoter of ST6GALNAC1 overlapping a previously reported rare genomic duplication observed in SZ. The mean DNA methylation difference at this locus was 6%, but there was considerable heterogeneity between families, with some twin pairs showing a 20% difference in methylation. We subsequently assessed this region in an independent sample of postmortem brain tissue from affected individuals and controls, finding marked hypomethylation (>25%) in a subset of psychosis patients. Overall, our data provide further evidence to support a role for DNA methylation differences in mediating phenotypic differences between MZ twins and in the etiology of both SZ and BD.


Subject(s)
Bipolar Disorder/genetics , Epigenesis, Genetic , Genetic Predisposition to Disease , Schizophrenia/genetics , Twins, Monozygotic/genetics , CpG Islands/genetics , DNA Methylation/genetics , Demography , Female , Gene Regulatory Networks/genetics , Genome, Human/genetics , Humans , Male , Promoter Regions, Genetic , Reproducibility of Results , Young Adult
15.
Bipolar Disord ; 13(3): 260-71, 2011 May.
Article in English | MEDLINE | ID: mdl-21676129

ABSTRACT

OBJECTIVES: Gamma oscillations have been proposed to play an important role in neural information coding. There have been a limited number of electrophysiology studies in evoked gamma band responses (GBRs) in bipolar disorder (BPD). It is also unclear whether GBR deficits, if present, are potential endophenotypes for BPD as little is known about the heritability of GBRs. The present study aimed to examine whether GBRs derived from two auditory tasks, the oddball task and the dual-click paradigm, are potential BPD endophenotypes. METHODS: A total of 308 subjects were included in this study: 198 healthy controls, 59 BPD patients (22 monozygotic BPD twins and 37 BPD patients from 31 families), and 51 unaffected relatives. The evoked gamma responses were calculated using a Morlet wavelet transformation. Structural equation modelling was applied to obtain the genetic (heritability) and environment estimates in each GBR variable and their (genetic) overlap with BPD. RESULTS: The heritability estimates of GBR to standard stimuli were 0.51 and 0.35 to target stimuli in the oddball task. However, neither response type was impaired in BPD patients or their unaffected relatives. The heritability estimates of GBR to S1 stimuli were 0.54 and 0.50 to S2 stimuli in the dual-click paradigm. BPD patients had reduced gamma power and suppression to S1 stimuli but their unaffected relatives did not. CONCLUSIONS: Evoked GBRs are heritable traits. However, GBR deficits are not observed in clinically unaffected relatives nor associated with BPD. Gamma responses do not appear to satisfy criteria for being BPD endophenotypes.


Subject(s)
Bipolar Disorder/genetics , Bipolar Disorder/physiopathology , Brain Mapping , Environment , Evoked Potentials, Auditory/genetics , Acoustic Stimulation/methods , Adolescent , Adult , Discrimination, Psychological , Diseases in Twins , Electroencephalography/methods , Evoked Potentials, Auditory/physiology , Family , Family Health , Female , Humans , Linear Models , Male , Middle Aged , Neuropsychological Tests , Twins, Dizygotic/genetics , Twins, Monozygotic/genetics , Young Adult
16.
Neuroimage ; 49(1): 939-46, 2010 Jan 01.
Article in English | MEDLINE | ID: mdl-19699306

ABSTRACT

Perception of fearful faces is associated with functional activation of cortico-limbic structures, which has been found altered in individuals with psychiatric disorders such as schizophrenia, autism and major depression. The objective of this study was to isolate the brain response to the features of standardized fearful faces by incorporating principal component analysis (PCA) into the analysis of neuroimaging data of healthy volunteers and individuals with schizophrenia. At the first stage, the visual characteristics of morphed fearful facial expressions (FEEST, Young et al., 2002) were classified with PCA, which produced seven orthogonal factors, with some of them related to emotionally salient facial features (eyes, mouth, brows) and others reflecting non-salient facial features. Subsequently, these PCA-based factors were included into the functional magnetic resonance imaging (fMRI) analysis of 63 healthy volunteers and 32 individuals with schizophrenia performing a task that involved implicit processing of FEEST stimuli. In healthy volunteers, significant neural response was found to visual characteristics of eyes, mouth or brows. In individuals with schizophrenia, PCA-based analysis enabled us to identify several significant clusters of activation that were not detected by the standard approach. These clusters were implicated in processing of visual and emotional information and were attributable to the perception of eyes and brows. PCA-based analysis could be useful in isolating brain response to salient facial features in psychiatric populations.


Subject(s)
Facial Expression , Fear/psychology , Schizophrenia/physiopathology , Schizophrenic Psychology , Adult , Brain/physiopathology , Echo-Planar Imaging , Female , Humans , Image Processing, Computer-Assisted , Male , Oxygen/blood , Principal Component Analysis
17.
Schizophr Res ; 115(2-3): 237-44, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19786340

ABSTRACT

BACKGROUND: Genetic factors are important in the aetiology of psychotic disorders, but it is unclear how far they influence aspects of illness history within psychoses. AIMS: To investigate the extent, and type of familial aggregation for a range of illness history variables in psychosis. METHODS: Two-hundred-and-twenty-four proband-wise twin pairs (106 monozygotic, 118 same-sex dizygotic), where probands had psychosis, were ascertained from the Maudsley Twin Register in London. We investigated the following illness history variables, rated using the OPCRIT checklist: age at onset; chronicity of course; mode of onset; psychotic/affective predominance; pre-morbid social adjustment; and the presence of a psychosocial precipitant. We used Mx statistical modelling software to analyse correlations of variables within pairs of monozygotic twins concordant for psychosis; and relationships between variables in probands and risk of psychosis in monozygotic and dizygotic co-twins. RESULTS: There was a high monozygotic within-pair correlation for age at onset (intra-class correlation=0.9); moderate correlations for chronicity of course (polychoric correlation=0.4) and psychotic/affective predominance (polychoric correlation=0.5); and lower non-significant correlations for other variables. No variables consistently predicted risk of psychosis in co-twins. CONCLUSIONS: Illness history variables in psychosis show a broad range of familial aggregation. It is likely that familial influences are predominantly modifying effects, independent of susceptibility factors for psychosis.


Subject(s)
Diseases in Twins/genetics , Genetic Predisposition to Disease , Psychotic Disorders/genetics , Psychotic Disorders/psychology , Age Factors , Checklist , Diseases in Twins/psychology , Humans , Models, Statistical , Phenotype , Psychiatric Status Rating Scales , Risk Assessment , Sex Factors , Twin Studies as Topic , Twins/genetics
18.
Hum Brain Mapp ; 30(10): 3287-98, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19479729

ABSTRACT

During verbal-fluency tasks, impairments in performance and functional abnormalities in the inferior frontal cortex have been observed in both schizophrenia patients and their unaffected relatives. We sought to examine whether such functional abnormalities are a specific marker of genetic vulnerability to schizophrenia. We studied a sample of 132 subjects, comprising 39 patients with schizophrenia, 10 unaffected monozygotic (MZ) cotwins of schizophrenia probands, 28 patients with bipolar disorder, 7 unaffected MZ cotwins of bipolar disorder probands and 48 healthy controls. Blood oxygen level-dependent response was measured using functional magnetic resonance imaging during the performance of an overt verbal-fluency task with two levels of task difficulty, in a cytoarchitectonic region of interest encompassing Brodmann areas 44 and 45 bilaterally. Patients with schizophrenia and the unaffected MZ cotwins of schizophrenia probands showed increased activation in the inferior frontal cortex relative to healthy controls and bipolar patients. Increased engagement of the inferior frontal cortex during verbal-fluency may thus be a marker of genetic vulnerability to schizophrenia.


Subject(s)
Bipolar Disorder/pathology , Brain Mapping , Frontal Lobe/physiopathology , Schizophrenia/genetics , Schizophrenia/pathology , Verbal Behavior/physiology , Adult , Diseases in Twins , Female , Frontal Lobe/blood supply , Humans , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Male , Markov Chains , Middle Aged , Neuropsychological Tests , Oxygen/blood , Schizophrenia/complications , Speech Disorders/etiology , Speech Disorders/pathology
19.
Br J Psychiatry ; 194(3): 285-6, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19252161

ABSTRACT

We analysed Stroop (neuropsychological screening test) measures of response inhibition in 18 twin pairs discordant for bipolar I disorder compared with 17 healthy control pairs, as well as 40 singletons with bipolar disorder with psychotic features and a family history of psychosis, 46 of their first-degree relatives without bipolar disorder or psychosis and 48 controls. In both studies, individuals with bipolar disorder showed Stroop deficits and their first-degree relatives showed intact performance. In the twin patients, an interference score was associated with depressive symptoms. Having a first-degree relative with bipolar disorder, even a familial, psychotic form, did not confer risk for enhanced susceptibility to interference in our studies.


Subject(s)
Bipolar Disorder/genetics , Diseases in Twins/genetics , Genetic Predisposition to Disease/genetics , Pedigree , Psychotic Disorders/genetics , Bipolar Disorder/diagnosis , Bipolar Disorder/psychology , Case-Control Studies , Cognition Disorders/diagnosis , Cognition Disorders/genetics , Cognition Disorders/psychology , Diseases in Twins/psychology , Genetic Predisposition to Disease/psychology , Humans , Neuropsychological Tests , Psychotic Disorders/diagnosis , Psychotic Disorders/psychology
20.
Biol Psychiatry ; 65(6): 473-80, 2009 Mar 15.
Article in English | MEDLINE | ID: mdl-19054502

ABSTRACT

BACKGROUND: Catechol-O-methyltransferase (COMT) is essential for dopamine metabolism in the brain, and normal variation in the COMT Val158Met polymorphism can influence regional brain function during cognitive tasks. How this is affected when central dopamine function is perturbed is unclear. We addressed this by comparing the effects of COMT Val158Met genotype on cortical activation during a task of executive functions in healthy and schizophrenic subjects. METHODS: We studied 90 subjects comprising 48 healthy volunteers (15 Met158/Met158, 20 Val158/Met158, and 13 Val158/Val158) and 42 patients with DSM-IV schizophrenia (13 Met158/Met158, 17 Val158/Met158, and 12 Val158/Val158). Subjects were studied with functional magnetic resonance imaging while performing a verbal fluency task, with performance recorded online. Main effects of genotype and diagnosis and their interaction on cortical activation and functional connectivity were assessed using SPM5. RESULTS: In the right peri-Sylvian cortex, the Met158 allele of the COMT Val158Met polymorphism was associated with greater activation than the Val158 allele in control subjects; the converse applied in patients (Z = 4.3; false discovery rate p = .04). There was also a strong trend for a group x genotype interaction on functional connectivity between this right peri-Sylvian region and the left anterior insula/operculum (Z = 3.4; p < .001, uncorrected). These findings were independent of between-group differences in task performance, medication, demographic factors, or IQ. CONCLUSIONS: Frontotemporal function during verbal generation is modulated by variation in COMT genotype. This effect is altered in schizophrenia, which may reflect the perturbation of central dopamine function associated with the disorder.


Subject(s)
Catechol O-Methyltransferase/genetics , Cerebral Cortex/physiopathology , Schizophrenia/genetics , Schizophrenia/physiopathology , Schizophrenic Psychology , Adult , Case-Control Studies , Cognition , Female , Genotype , Humans , Language Tests , Male , Neural Pathways/physiopathology , Polymorphism, Single Nucleotide
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