Showing papers by "Robin M. Murray published in 2007"
TL;DR: It is suggested that the degree of lateralization of perisylvian pathways is heterogeneous in the normal population and, paradoxically, bilateral representation, not extreme lateralization, might ultimately be advantageous for specific cognitive functions.
Abstract: Lateralization of language to the left hemisphere is considered a key aspect of human brain organization. We used diffusion tensor MRI to perform in vivo virtual dissection of language pathways to assess the relationship between brain asymmetry and cognitive performance in the normal population. Our findings suggest interhemispheric differences in direct connections between Broca's and Wernicke's territories, with extreme leftward lateralization in more than half of the subjects and bilateral symmetrical distribution in only 17.5% of the subjects. Importantly, individuals with more symmetric patterns of connections are better overall at remembering words using semantic association. Moreover, preliminary analysis suggests females are more likely to have a symmetrical pattern of connections. These findings suggest that the degree of lateralization of perisylvian pathways is heterogeneous in the normal population and, paradoxically, bilateral representation, not extreme lateralization, might ultimately be advantageous for specific cognitive functions.
593 citations
TL;DR: The debate between the protagonists and prohibitionists has recently been re-ignited, but unfortunately this debate continues mainly in ignorance of the new understanding of the effects of cannabis on the brain and of studies that have quantified the extent of the risks of long-term use.
Abstract: Cannabis has been known for at least 4,000 years to have profound effects on the mind--effects that have provoked dramatically divergent attitudes towards it. Some societies have regarded cannabis as a sacred boon for mankind that offers respite from the tribulations of everyday life, whereas others have demonized it as inevitably leading to 'reefer madness'. The debate between the protagonists and prohibitionists has recently been re-ignited, but unfortunately this debate continues mainly in ignorance of our new understanding of the effects of cannabis on the brain and of studies that have quantified the extent of the risks of long-term use.
323 citations
TL;DR: The causes of and pathways to clinical psychotic disorder can be studied long before the disorder becomes clinically relevant, and individuals with a persistently high level of either of the two identified symptom dimensions over 20 years experienced significant deficiencies in social achievement and functioning.
299 citations
TL;DR: Within the patient group, the propensity to experience auditory hallucinations was associated with relatively increased fractional anisotropy in superior longitudinal fasciculi and in the anterior cingulum, whereas within the healthy comparison subjects, this was not the case.
Abstract: Objective: Cognitive models propose that the symptoms and psychological impairments associated with schizophrenia arise as a consequence of impaired communication between brain regions, especially the prefrontal cortex and the temporal and parietal lobes. Functional imaging and electrophysiological data have provided evidence of functional dysconnectivity, but it is unclear whether this reflects an underlying problem with anatomical connectivity. This study used diffusion tensor imaging to examine the integrity of the major white matter fasciculi, which connects the frontal and temporal-parietal cortices, and the corpus callosum in patients with schizophrenia. Method: A 1.5-T magnetic resonance scanner was used to acquire diffusion tensor images giving whole brain coverage at an isotropic 2.5-mm voxel size. Fractional anisotropy was measured in 33 patients with schizophrenia and 40 healthy comparison subjects with an automated voxel-based method of analysis. Results: There was reduced fractional anisotropy in patients with schizophrenia in regions corresponding to the superior longitudinal fasciculi bilaterally and in the genu of the corpus callosum. However, within the patient group, the propensity to experience auditory hallucinations was associated with relatively increased fractional anisotropy in superior longitudinal fasciculi and in the anterior cingulum. Conclusions: Schizophrenia is associated with altered white matter integrity in the tracts connecting the frontal cortex with the temporal and parietal cortices and with the contralateral frontal and temporal lobes. The severity of these changes may vary with the pattern of symptoms associated with the disorder. Abstract Teaser
271 citations
01 Apr 2007
TL;DR: Cases of psychotic disorder could be prevented by discouraging cannabis use among vulnerable youths, and cannabis use appears to be neither a sufficient nor a necessary cause for psychosis.
Abstract: Background:Controversy remains as to whether cannabis acts as a causal risk factor for schizophrenia or other functional psychotic illnesses. Aims: To examine critically the evidence that cannabis causes psychosis using established criteria of causality. Method: We identified five studies that included a well-defined sample drawn from population-based registers or cohorts and used prospective measures of cannabis use and adult psychosis. Results: On an individual level, cannabis use confers an overall twofold increase in the relative risk for later schizophrenia. At the population level, elimination of cannabis use would reduce the incidence of schizophrenia by approximately 8%, assuming a causal relationship. Cannabis use appears to be neither a sufficient nor a necessary cause for psychosis. It is a component cause, part of a complex constellation of factors leading to psychosis. Conclusions: Cases of psychotic disorder could be prevented by discouraging cannabis use among vulnerable youths. Research is...
239 citations
TL;DR: Separation from, and death of, a parent before the age of 16 were both strongly associated with a two- to threefold increased risk of psychosis and the strength of these associations were similar for White British and Black Caribbean (but not Black African) subjects.
Abstract: Background. Numerous studies have reported high rates of psychosis in the Black Caribbean and Black African populations in the UK. However, few studies have investigated the role of specific risk factors in different ethnic groups. We sought to investigate the relationship between long-term separation from, and death of, a parent before the age of 16 and risk of adult psychosis in different ethnic groups. Method. All patients with a first episode of psychosis who made contact with psychiatric services in defined catchment areas in London and Nottingham, UK and a series of community controls were included in the AESOP (Aetiology and Ethnicity in Schizophrenia and Other Psychoses) study. Data relating to clinical and social variables, including parental separation and loss, were collected from patients and controls. Results. Separation from, and death of, a parent before the age of 16 were both strongly associated with a two- to threefold increased risk of psychosis. The strength of these associations were similar for White British and Black Caribbean (but not Black African) subjects. Separation from (but not death of) a parent was more common among Black Caribbean controls than White British controls. Conclusions. Early separation may have a greater impact in the Black Caribbean population, because it is more common, and may contribute to the excess of psychosis in this population.
238 citations
TL;DR: The results suggest that questionnaire screening of community samples of children for the putative antecedents of schizophrenia spectrum disorders is feasible and accuracy of identification will only be established by follow-up studies.
201 citations
TL;DR: A variant on the neurodevelopment and dopamine hypotheses of schizophrenia is proposed, whereby an early dysfunction in GSK-3 regulation has neurodevelopmental consequences that predispose to disease and the Wnt and insulin signalling pathways become targets for therapy.
200 citations
TL;DR: SERFs at individual and neighbourhood levels were implicated in the aetiology of psychosis, but it was unable to determine whether these associations were causal.
Abstract: BackgroundThe incidence of schizophrenia varies by individual-level characteristics and neighbourhood-level attributes. Few specific socio-environmental risk factors (SERFs) have been identified at the neighbourhood level. Cross-level interactions are poorly understood. We investigated these issues using data from the Aetiology and Ethnicity in Schizophrenia and Other Psychoses (AESOP) study.MethodAll incidence cases of ICD-10 schizophrenia (F20) and other non-affective psychoses (F21–29), aged 16–64 years, across 33 wards in Southeast London were identified over a 2-year period (1997–1999). Census data provided the denominator for each ward. Multilevel Poisson regression simultaneously modelled individual- and neighbourhood-level SERFs, including socio-economic deprivation, voter turnout (proxy for social capital), ethnic fragmentation (segregation) and ethnic density.ResultsA total of 218 subjects were identified during 565 576 person-years at risk. Twenty-three per cent of variance in incidence of schizophrenia across wards could be attributed to neighbourhood-level risk factors [95% confidence interval (CI) 9·9–42·2]. Thus, 1% increases in voter turnout [incidence rate ratio (IRR) 0·95, 95% CI 0·92–0·99] and ethnic segregation (IRR 0·95, 95% CI 0·92–0·99) were both independently associated with a reduced incidence of 5%, independent of age, sex, ethnicity, deprivation and population density. This was similar for other non-affective psychoses. There was some evidence that ethnic minority individuals were at greater risk of schizophrenia in areas with smaller proportions of minority groups (p=0·07).ConclusionSERFs at individual and neighbourhood levels were implicated in the aetiology of psychosis, but we were unable to determine whether these associations were causal. Individual risk may be mediated by social capital, which could operate as a protective factor, perhaps moderating social stress in the onset of psychoses.
198 citations
TL;DR: The results suggest that, although free from major physical disability, VPT young adults perform worse than controls on tasks involving selective aspects of executive processing, such as mental flexibility and response inhibition.
Abstract: Individuals born very preterm (VPT) are at increased risk of perinatal brain injury and long-term cognitive and behavioral problems. Executive functioning, in particular, has been shown to be impaired in VPT children and adolescents. This study prospectively assessed executive function in young adults who were born VPT (<33 weeks of gestation) [n = 61; mean age, 22.25 (+/-1.07) years; range, 20.62-24.78 years] and controls [n = 64; mean age, 23.20 (+/-1.48) years; range, 19.97-25.46 years]. Tests used comprised the Wechsler Abbreviated Scale of Intelligence (WASI), the Hayling Sentence Completion Test (HSCT), the Controlled Oral Word Association Test (COWAT), the Animal and Object test, the Trail-Making Test (TMT), and the Test of Attentional Performance (TAP). VPT participants showed specific executive function impairments in tasks involving response inhibition and mental flexibility, even when adjusting for IQ, gender, and age. No significant associations were observed between executive function test scores and perinatal variables or neonatal ultrasound classification. The results suggest that, although free from major physical disability, VPT young adults perform worse than controls on tasks involving selective aspects of executive processing, such as mental flexibility and response inhibition.
186 citations
TL;DR: The dopamine hypothesis has been the major pathophysiological theory of psychosis in recent decades as mentioned in this paper, and molecular imaging studies have provided in vivo evidence of increased dopamine synaptic availability and increased presynaptic dopamine synthesis in the striata of people with psychotic illnesses.
Abstract: The dopamine hypothesis has been the major pathophysiological theory of psychosis in recent decades. Molecular imaging studies have provided in vivo evidence of increased dopamine synaptic availability and increased presynaptic dopamine synthesis in the striata of people with psychotic illnesses. These studies support the predictions of the dopamine hypothesis, but it remains to be determined whether dopaminergic abnormalities pre-date or are secondary to the development of psychosis. We selectively review the molecular imaging studies of the striatal dopaminergic system in psychosis and link this to models of psychosis and the functional subdivisions of the striatum to make predictions for the dopaminergic system in the prodromal phase of psychosis.
TL;DR: Evidence indicates that, although the neurochemical origins of schizophrenia do not necessarily lie in dopamine dysregulation, this operates as the final common pathway underlying positive psychotic symptoms and may also play a role in negative and cognitive symptoms.
TL;DR: Combined cognitive-behavioural therapy and motivational interviewing seems a promising psychological intervention to achieve a cessation of cannabis use in patients suffering from schizophrenia.
Abstract: Purpose of reviewCannabis is the world's most commonly used illicit drug. In this review, we consider the recent literature on the effects of cannabis on mental health and on cognition.Recent findingsCannabis use in adolescence increases the risk of later schizophrenia-like psychoses, especially in
TL;DR: All four event-related potential indices are potentially valid endophenotypes for schizophrenia, but P50 suppression and P300 amplitude show the closest genetic relationship to schizophrenia.
Abstract: Objective: Several components of event-related potentials—P50 suppression, P300 amplitude and latency, and mismatch negativity—have been proposed as potential endophenotypes for schizophrenia on the basis of family studies. The present study used a twin design to estimate the extent of genetic overlap between these indices and the liability to schizophrenia. Method: The authors measured mismatch negativity, P300, and P50 suppression in 16 monozygotic twin pairs concordant for schizophrenia, nine monozygotic twin pairs discordant for schizophrenia, and 78 healthy comparison twin pairs. The study design was based on a power calculation. Structural equation modeling was used to quantify the genetic and environmental contributions to the phenotypic covariance between schizophrenia and each of the event-related potential indices. Results: Significant phenotypic correlation with schizophrenia was found for each of the event-related potential components. Genetic factors were the main source of the phenotypic cor...
TL;DR: Suicide is significantly increased in unselected bipolar patients but actual case fatality is not as high as previously claimed, and a history of alcohol abuse and deterioration in function predict suicide in bipolar disorder.
Abstract: Background. The high risk of suicide in bipolar disorder is well recognized, but may have been overestimated. There is conflicting evidence about deaths from other causes and little known about risk factors for suicide. We aimed to estimate suicide and mortality rates in a cohort of bipolar patients and to identify risk factors for suicide.Method. All patients who presented for the first time with a DSM-IV diagnosis of bipolar I disorder in a defined area of southeast London over a 35-year period (1965–1999) were identified. Mortality rates were compared with those of the 1991 England and Wales population, indirectly standardized for age and gender. Univariate and multivariate analyses were used to test potential risk factors for suicide.Results. Of the 239 patients in the cohort, 235 (98·3%) were traced. Forty-two died during the 4422 person-years of follow-up, eight from suicide. The standardized mortality ratio (SMR) for suicide was 9·77 [95% confidence interval (CI) 4·22–19·24], which, although significantly elevated compared to the general population, represented a lower case fatality than expected from previous literature. Deaths from all other causes were not excessive for the age groups studied in this cohort. Alcohol abuse [hazard ratio (HR) 6·81, 95% CI 1·69–27·36, p=0·007] and deterioration from pre-morbid level of functioning up to a year after onset (HR 5·20, 95% CI 1·24–21·89, p=0·024) were associated with increased risk of suicide.Conclusions. Suicide is significantly increased in unselected bipolar patients but actual case fatality is not as high as previously claimed. A history of alcohol abuse and deterioration in function predict suicide in bipolar disorder.
TL;DR: Neighbourhood variation in the incidence of non-affective psychoses could not be explained by individual-level risk, implicating neighbourhood-level socioenvironmental factors in their aetiology.
Abstract: Background
Urbanicity is a risk factor for schizophrenia, but it is unclear whether this risk is homogenous across urban areas.
TL;DR: The results suggest that impaired P50 gating is a putative endophenotype for psychotic bipolar disorder and thus might reflect the impact of susceptibility genes across psychosis and suggest the relationship to genetic liability in bipolar disorder is unknown.
TL;DR: Aggressive behaviour was associated with a diagnosis of mania and individual manic symptoms were also associated with aggression both for the whole sample and for those with schizophrenia, which is not an uncommon feature in those presenting with first episode psychosis.
Abstract: BACKGROUND: Aggressive behaviour is increased among those with schizophrenia but less is known about those with affective psychoses. Similarly, little is known about aggressive behaviour occurring at the onset of illness. METHOD: The main reasons for presentation to services were examined among those recruited to a UK-based first episode psychosis study. The proportion of individuals presenting with aggressive behaviour was determined and these individuals were compared to those who were not aggressive on a range of variables including sociodemographic, clinical, criminal history, service contact, and symptom characteristics. Among the aggressive group, those who were physically violent were distinguished from those who were not violent but who were still perceived to present a risk of violence to others. RESULTS: Almost 40% (n=194) of the sample were aggressive at first contact with services; approximately half of these were physically violent (n=103). Younger age, African-Caribbean ethnicity and a history of previous violent offending were independently associated with aggression. Aggressive behaviour was associated with a diagnosis of mania and individual manic symptoms were also associated with aggression both for the whole sample and for those with schizophrenia. Factors differentiating violent from non-violent aggressive patients included male gender, lower social class and past violent offending. CONCLUSIONS: Aggressive behaviour is not an uncommon feature in those presenting with first episode psychosis. Sociodemographic and past offending factors are associated with aggression and further differentiate those presenting with more serious violence. A diagnosis of mania and the presence of manic symptoms are associated with aggression. Language: en
TL;DR: Patients receiving treatment for schizophrenia or schizoaffective disorder show high rates of sexual dysfunction and hypogonadism, and sexual functioning was not related to prolactin or gonadal hormone levels.
Abstract: Sexual dysfunction is common in patients taking antipsychotics- more than twice as common as in healthy controls 1;2, and greater in patients taking antipsychotics than unmedicated schizophrenic patients and patients with affective disorders 3-5. The CATIE study has recently highlighted that sexual function is commonly impaired in patients taking atypical as well as typical antipsychotic treatment 6. A number of factors may play a role in impairing sexual dysfunction in patients taking antipsychotic treatment, including ‘negative’ and co-morbid depressive symptoms, the anticholinergic and adrenergic effects of antipsychotics, and higher rates of smoking and physical illness2;7. It has long been supposed, however, that prolactin elevation and low gonadal hormone levels are significant factors underlying the high rates of sexual dysfunction seen in patients treated with antipsychotics8-10. Prolactin may impair sexual function through its actions on the hypothalamic-pituitary-gonadal axis altering sex hormone release. Hyperprolactinemia is associated with hypogonadism and sexual dysfunction11, although a preliminary naturalistic study of women taking antipsychotics found high but similar rates of reproductive dysfunction in normoprolactinemic and hyperprolactinemic groups 12. Low sex hormone levels have been reported in patients taking antipsychotics 13-16. We have previously reported high rates of sexual dysfunction and high rates of hypogonadism in patients taking antipsychotics 1, but no previous studies have investigated the association between the two. We hypothesised that low sex hormone levels are associated with sexual dysfunction in patients taking antipsychotics.
We therefore set out to substantiate the finding that rates of sexual dysfunction are higher in patients taking antipsychotics than healthy controls in a larger sample and to test the hypothesis that sexual dysfunction is associated with prolactin, and gonadal hormone levels in patients taking antipsychotic treatment for schizophrenia or schizo-affective disorder.
TL;DR: Supporting evidence is provided that P300 amplitude and P50 suppression ratio are ERP endophenotypes for bipolar disorder.
Abstract: Background. Electrophysiological endophenotypes are far less explored in bipolar disorder as compared to schizophrenia. No previous twin study of event-related potentials (ERPs) in bipolar illness has been reported. This study uses a twin design and advanced genetic model fitting analyses aiming to (1) assess and quantify the relationship of a range of ERP components with bipolar disorder with psychotic features, and (2) examine the source of the relationship (due to genetic or environmental factors). Method. P300, P50 suppression and mismatch negativity (MMN) were recorded in 10 discordant monozygotic (MZ) bipolar twin pairs, six concordant MZ bipolar twin pairs and 78 control twin pairs. Statistical analyses were based on structural equation modelling. Results. Bipolar disorder was significantly associated with smaller P300 amplitude and decreased P50 suppression. Genetic correlations were the main source of the associations, estimated to be x0 . 33 for P300 amplitude and 0 . 46 for P50 ratio. Individual-specific environmental influences were not significant. MMN and P300 latency were not associated with the illness. Conclusions. The results provide supporting evidence that P300 amplitude and P50 suppression ratio are ERP endophenotypes for bipolar disorder.
TL;DR: The diagnostic criteria for schizophrenia in the fourth edition of the DSM-IV1 are based on the premise that it is a discrete illness entity, in particular, distinct from the affective psychoses as mentioned in this paper.
Abstract: The diagnostic criteria for schizophrenia in the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV1) are based on the premise that it is a discrete illness entity, in particular, distinct from the affective psychoses. This assumption has persisted for more than a century, even though patients with a diagnosis of schizophrenia show a wide diversity of symptoms and outcomes, and no biological or psychological feature has been found to be pathognomonic of the disorder. However, there has been sustained, and indeed growing, criticism of the concept. For example, writing about the diagnosis of schizophrenia more than a decade ago,2 one of Britain's most sophisticated nosological experts, Ian Brockington, enjoined “It is important to loosen the grip which the concept of ‘schizophrenia’ has on the minds of psychiatrists. Schizophrenia is an idea whose very essence is equivocal, a nosological category without natural boundaries, a barren hypothesis. Such a blurred concept is ‘not a valid object of scientific enquiry’.”3 Should Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition(DSM-V), persist with the neo-Kraepelinian concept of schizophrenia with all its defects, or should it deconstruct psychosis into its component dimensions? In this article, we will address the question by considering 2 main themes, firstly, the role of culture and ethnicity in the diagnosis of psychosis, and secondly, a life course approach to understanding psychosis. We will then discuss whether more progress would be achieved in DSM-V by abandoning the familiar categorical system and instead moving to a dimensional system which rates both developmental impairment and symptom factor scores. However, we will begin by briefly reviewing the recent history of the classification of the psychoses.
TL;DR: Volumetric thalamic abnormalities in schizophrenia occur in twin pairs concordant for schizophrenia, whereas the adhesio interthalamica is unlikely to be affected in schizophrenia.
Abstract: Context Abnormalities of the thalamus are thought to be central to the pathophysiology of schizophrenia. These abnormalities include altered structure and shape of the thalamus itself and possibly changes to the adhesio interthalamica (or massa intermedia), the gray matter bridge connecting the 2 thalamic lobes. However, it is not clear to what extent these abnormalities are determined by the genetic liability for schizophrenia. Objective To investigate thalamic volume and the presence of the adhesio interthalamica in monozygotic (MZ) twins concordant or discordant for schizophrenia. Design Study of MZ twins. Setting Patients were drawn from inpatient and outpatient clinics. Twin controls were recruited from a volunteer twin register and through media advertisements. Participants A total of 123 twins participated: 19 MZ twin pairs concordant for schizophrenia, 15 MZ schizophrenic twins and 16 MZ nonschizophrenic twins drawn from 17 pairs discordant for schizophrenia, and 27 MZ twin pairs without schizophrenia. Groups were matched for age, sex, handedness, level of education, parental socioeconomic status, and ethnicity. Main Outcome Measures The volume of the thalamus (including right and left hemispheres) was measured (in cubic centimeters) and the presence of the adhesio interthalamica was ascertained from structural magnetic resonance images. Results Concordant twin pairs displayed significantly reduced thalamic volume compared with control twins, even when covarying for effects of whole-brain volume, age, and sex. There was a significant linear decrease in thalamic volume (control greater than discordant nonschizophrenic greater than discordant schizophrenic greater than concordant). In all groups, right thalamus was larger than left thalamus. There was no difference across groups in the frequency of the adhesio interthalamica. Conclusions Volumetric thalamic abnormalities in schizophrenia occur in twin pairs concordant for schizophrenia. These abnormalities may mark the substantial genetic contribution to the illness seen in concordant twin pairs, whereas the adhesio interthalamica is unlikely to be affected in schizophrenia.
TL;DR: Incidence of psychosis in São Paulo was lower than expected for a large metropolis and almost 40% fulfilled criteria for schizophrenia or schizophreniform disorder.
Abstract: Background Little is known about the incidence of first-episode psychosis in urban centres of low- or middle-income countries.
Aims To estimate the incidence of psychosis in Sao Paulo, a large metropolis of Brazil.
Method Prospective survey of first-episode psychosis among residents aged 18–64 years resident in a defined area of Sao Paulo, over a 30-month period (July 20 2002–December 2004). Assessments were carried out withthe SCID–I, and diagnoses given according to DSM–IV criteria. Population at risk was drawn from the 2000 Census data.
Results There were 367 first-episode cases identified (51% women), and almost 40% fulfilled criteria for schizophrenia or schizophreniform disorder. The incidence rate for any psychosis was 15.8/100 000 person-years at risk (95% CI 14.3–17.6). Incidence of non-affective psychoses was higher among younger males.
Conclusions Incidence of psychosisin Sao Paulo was lower than expected for a large metropolis.
TL;DR: Findings show that selected neurocognitive deficits especially attention and executive function are impaired in the families of schizophrenic patients, which may represent “endophenotypes” denoting varying degrees of vulnerability to schizophrenia and may be of value in future molecular genetic studies.
Abstract: Some neuropsychological abilities, particularly those affecting memory, attention and executive function, are impaired amongst both schizophrenic patients and their unaffected relatives, implying that these deficits are at least partly genetic in origin. However neuropsychological performance can be altered by medication, and has rarely been examined in first onset, drug naive patients. The objective of this study was to determine whether selected neurocognitive abilities are impaired in first-onset schizophrenic patients and their relatives compared to controls. We examined attention and speed of information processing, memory and learning, verbal function, visuoconstructive abilities and executive function in 207 first-episode schizophrenic patients (163 of whom were drug naive), 322 of their first-degree relatives and 133 unrelated normal controls. The data were subjected to multilevel modeling to compare neurocognitive performance between schizophrenic probands, relatives and controls while taking into account potential correlations among members of the same family; age, gender, and years of education were included as covariates. Of the three groups, schizophrenic patients performed poorest at all neuropsychological tests, suggestive of a broad range of neurocognitive deficits. Their first-degree relatives showed a narrower pattern of poor performance at Digit Symbol, Digit Span, Trail Making, Verbal Fluency test, Tower of Hanoi, and WCST-M tests. Our findings show that selected neurocognitive deficits especially attention and executive function are impaired in the families of schizophrenic patients. These patterns of neurocognitive deficits may represent "endophenotypes" denoting varying degrees of vulnerability to schizophrenia and may be of value in future molecular genetic studies.
TL;DR: Whether patients experiencing their first episode of psychosis have worse physical health and lifestyle than community controls without psychosis is established and some risk factors for physical health problems may be explained by unemployment.
Abstract: Background
There is an increased prevalence of physical illness and poor lifestyle in patients with chronic schizophrenia. It is unclear whether these are present at the onset of psychosis or develop over the course of illness. We aimed to establish whether patients experiencing their first episode of psychosis have worse physical health and lifestyle than community controls without psychosis.
01 Jan 2007
TL;DR: Genomewide searches using factorial designs stratifying for levels of intelligence and working memory will assist in the search for finding quantitative trait loci for schizophrenia.
Abstract: Results: Genetic influences contributed substantially to all of the cognitive domains, but intelligence and working memory were the most heritable. A significant correlation was found between intelligence and schizophrenia (r=�0.61; 95% confidence interval, �0.71 to �0.48), with shared genetic variance accounting for 92% of the covariance between the two. Genetic influences also explained most of the covariance between working memory and schizophrenia. Significant but lesser portions of covariance between the other cognitive domains and schizophrenia were also found to be genetically shared. Environmental effects, although separately linked to neurocognition and schizophrenia, did not generally contribute to their covariance. Conclusion: Genomewide searches using factorial designs stratifying for levels of intelligence and working memory will assist in the search for finding quantitative trait loci for schizophrenia. Arch Gen Psychiatry. 2007;64(12):1348-1355
TL;DR: Longer DUP is associated with poorer neurocognitive ability in schizophrenia subjects at time of first presentation, and this was a cross-sectional study so it can not tell whether longer DUP was a cause or a consequence of the poorer performance.
TL;DR: The use of the hit reaction time measure of the CPT as an endophenotype marker for schizophrenia was supported, indicating it is a trait rather than a state marker.
TL;DR: Clinicians should be aware of the increased risk of adverse pregnancy outcomes in women with affective psychosis, some of which may be preventable.
Abstract: Objectives: Affective psychosis has its peak incidence during the childbearing years, but little is known about the effects of the illness on pregnancy. We investigated risks of preterm delivery (PTD), low birthweight (LBW), births of infants small for their gestational age (SGA), stillbirth and infant death in births to mothers with affective psychosis using a nested case–control design within a cohort of 1,558,071 singleton births in Sweden during 1983–1997.
Methods: Using prospectively collected data from population registers, we compared the pregnancy outcomes of 5,618 births to women with affective psychosis with the outcomes of 46,246 births to unaffected mothers.
Results: Mothers with affective psychosis had elevated risk for giving birth to preterm, small or growth-retarded babies. The risk for stillbirth and infant death during the first year of life was not significantly higher. The risks were greatest in mothers receiving hospital treatment for affective disorder during pregnancy: (i) preterm delivery: odds ratio (OR) = 2.67, 95% confidence interval (CI) = 1.71–4.17; (ii) SGA: OR = 2.36; 95% CI = 1.34–4.16; (iii) low birthweight: OR = 2.22; 95% CI = 1.31–3.76; and (iv) stillbirth: OR = 2.19; 95% CI = 0.55–8.76. After adjustment for covariates, particularly smoking, the risks were attenuated but remained significant.
Conclusions: Clinicians should be aware of the increased risk of adverse pregnancy outcomes in women with affective psychosis, some of which may be preventable.
TL;DR: Structural abnormalities reported in psychosis in high-income countries are also present in first-episode psychosis in Brazil, and a similar pattern of decrease in grey matter relative to controls is exhibited.
Abstract: Background In low- and middle-income countries people with schizophrenia are reported to experience better outcomes than those in high-income countries.
Aims To examine structural brain differences in people with first-episode psychosis and controls in Brazil.
Method Magnetic resonance imaging using voxel-based morphometry was performed on 122 people with first-episode psychosis and 94 controls.
Results There were significant decreases in grey matter in the left superior temporal and inferior prefrontal cortices, insula bilaterally and the right hippocampal region in first-episode psychosis ( P <0.05, corrected for multiple comparisons). The subgroup of people with schizophrenia ( n =62) exhibited a similar pattern of decrease in grey matter relative to controls.
Conclusions Structural abnormalities reported in psychosis in high-income countries are also present in first-episode psychosis in Brazil.