Association of extent of cannabis use and psychotic like intoxication experiences in a multi-national sample of first episode psychosis patients and …

2021

AbstractBackgroundFirst episode psychosis (FEP) patients who use cannabis experience more frequent psychotic and euphoric intoxication experiences compared to controls. It is not clear whether this is consequent to patients being more vulnerable to the effects of cannabis use or to their heavier pattern of use. We aimed to determine whether extent of use predicted psychotic-like and euphoric intoxication experiences in patients and controls and whether this differs between groups.MethodsWe analysed data on patients who had ever used cannabis (n = 655) and controls who had ever used cannabis (n = 654) across 15 sites from six countries in the EU-GEI study (2010–2015). We used multiple regres…

O4.8. CAN YOU SPOT EMOTIONS? FACIAL EMOTION RECOGNITION AND GENETIC RISK FOR PSYCHOSIS

2019

Background Facial emotion recognition (FER) is a key component of social cognition which has been found consistently impaired in schizophrenia. Deficits in global facial affect recognition have been also found in First Episode Psychosis (FEP) with the same severity as at further stages, especially for anger recognition. Literature to date has shown intermediate emotion recognition ability in either people with family history for psychotic disorders and unaffected relatives of psychotic patients, in a continuum between patients and healthy controls. Furthermore, Polygenic Risk Score (PRS) for schizophrenia has been found associated with social cognition, especially with facial emotion identi…

The EUropean Network of National Schizophrenia Networks Studying Gene-Environment Interactions (EU-GEI)

2020

Funder: FP7 Ideas: European Research Council; doi: http://dx.doi.org/10.13039/100011199; Grant(s): HEALTH-F2-2010-241909

Are Polygenic Risk Scores for Major Mental Disorders Associated with General or Specific Psychosis Symptom dimensions?

2019

Background Psychotic symptoms can be conceptualised as dimensions of psychopathology cutting across diagnostic boundaries. Thus, they might be considered enhanced quantitative phenotypes to relate to genetic variants as summarised by Polygenic Risk Scores (PRSs) for Major Mental Disorders (MMDs), including Schizophrenia (SZ), Bipolar Disorder (BP), and Major Depressive Disorder (MDD). The objectives of this study were to: 1) identify the dimensional structure of symptoms at First Episode Psychosis (FEP), testing whether a bi-factor model statistically fits the conceptualization of psychosis as a single common construct (general psychosis factor) while also recognising multidimensionality (p…

THE RELATION OF THE PSYCHOSIS CONTINUUM WITH SCHIZOPHRENIA POLYGENIC RISK SCORE AND CANNABIS USE

2020

Transdiagnostic dimensions of psychopathology at first episode psychosis: findings from the multinational EU-GEI study.

2019

Background\ud The value of the nosological distinction between non-affective and affective psychosis has frequently been challenged. We aimed to investigate the transdiagnostic dimensional structure and associated characteristics of psychopathology at First Episode Psychosis (FEP). Regardless of diagnostic categories, we expected that positive symptoms occurred more frequently in ethnic minority groups and in more densely populated environments, and that negative symptoms were associated with indices of neurodevelopmental impairment.\ud \ud Method\ud This study included 2182 FEP individuals recruited across six countries, as part of the EUropean network of national schizophrenia networks st…

Synergistic effects of childhood adversity and polygenic risk in first-episode psychosis

2023

The European Network of National Schizophrenia Networks Studying Gene-Environment Interactions (EU-GEI) Project is funded by grant agreement HEALTH-F2-2010-241909 (Project EU-GEI) from the European Community’s Seventh Framework Programme.

The Relationship Between Polygenic Risk Scores and Cognition in Schizophrenia

2020

Abstract Background Cognitive impairment is a clinically important feature of schizophrenia. Polygenic risk score (PRS) methods have demonstrated genetic overlap between schizophrenia, bipolar disorder (BD), major depressive disorder (MDD), educational attainment (EA), and IQ, but very few studies have examined associations between these PRS and cognitive phenotypes within schizophrenia cases. Methods We combined genetic and cognitive data in 3034 schizophrenia cases from 11 samples using the general intelligence factor g as the primary measure of cognition. We used linear regression to examine the association between cognition and PRS for EA, IQ, schizophrenia, BD, and MDD. The results wer…

Migration history and risk of psychosis: results from the multinational EU-GEI study.

2022

The European Network of National Schizophrenia Networks Studying Gene-Environment Interactions (EU-GEI) Project was funded by grant agreement Health-F2-2010-241909 (Project EU-GEI) from the European Community’s Seventh Framework programme.

Perceived major experiences of discrimination, ethnic group, and risk of psychosis in a six-country case-control study

2021

AbstractBackgroundPerceived discrimination is associated with worse mental health. Few studies have assessed whether perceived discrimination (i) is associated with the risk of psychotic disorders and (ii) contributes to an increased risk among minority ethnic groups relative to the ethnic majority.MethodsWe used data from the European Network of National Schizophrenia Networks Studying Gene-Environment Interactions Work Package 2, a population-based case−control study of incident psychotic disorders in 17 catchment sites across six countries. We calculated odds ratios (OR) and 95% confidence intervals (95% CI) for the associations between perceived discrimination and psychosis using mixed-…

S77. JUMPING TO CONCLUSIONS AND FACIAL EMOTION RECOGNITION IMPAIRMENT IN FIRST EPISODE PSYCHOSIS ACROSS EUROPE

2018

Abstract Background Jumping to conclusions (JTC) is a well-established reasoning and data gathering bias found in patients with psychosis even at illness onset (First Episode Psychosis, FEP). Preliminary work in this field focused primarily on the association with delusions, although jumping to conclusions has also been found in non-deluded schizophrenia patients after remission, and in individual with at risk mental state. Moreover, psychotic patients tend to show impairments in social cognition, struggling in identifying, processing and interpreting social clues. Deficits in facial emotion recognition (FER) – a key component of the construct – represent a well-replicated finding in schizo…

T110. FIRST EPISODE PSYCHOTIC PATIENTS WITH A HISTORY OF FREQUENT CANNABIS USE EXPRESS MORE POSITIVE SYMPTOMS AT ILLNESS ONSET THAN THOSE WHO NEVER U…

2018

Abstract Background Robust evidence has demonstrated that cannabis use increases the risk to develop psychotic disorders. However, a limited number of studies have investigated if and how cannabis use influences psychopathology profiles at first episode psychosis (FEP). Based on the evidence that dopamine dysfunction contributes to explain positive symptoms in psychosis, and that the main cannabis’ psychoactive component, Δ9-Tetrahydrocannabinol (THC), modulates the dopamine system, we hypothesise that: 1) positive symptoms at FEP are more common among psychotic patients who used cannabis compared with never users; 2) this association is a dose-response relationship. Methods We analyzed a s…

Schizophrenia polygenic risk score and cannabis use modify psychosis expression in first episode psychosis patients and population controls

2019

AbstractBackgroundDiagnostic categories within the psychosis spectrum are widely used in clinical practice, however psychosis may occur on a continuum. Therefore, we explored whether the continuous distribution of psychotic symptoms across categories is a function of genetic as well as environmental risk factors, such as polygenic risk scores (PRSs) and cannabis use.MethodsAs part of the EU-GEI study, we genotyped first episode psychosis patients (FEP) and population controls, for whom transdiagnostic dimensions of psychotic symptoms or experiences were generated using item response bi-factor modelling. Linear regression was used, separately in patients and controls, to test the association…

FIRST EPISODE PSYCHOTIC PATIENTS WITH A HISTORY OF FREQUENT CANNABIS USE EXPRESS MORE POSITIVE SYMPTOMS AT ILLNESS ONSET THAN THOSE WHO NEVER USED CA…

2018

Background: Robust evidence has demonstrated that cannabis use increases the risk to develop psychotic disorders. However, a limited number of studies have investigated if and how cannabis use influences psychopathology profiles at first episode psychosis (FEP). Based on the evidence that dopamine dysfunction contributes to explain positive symptoms in psychosis, and that the main cannabis’ psychoactive component, Δ9-Tetrahydrocannabinol (THC), modulates the dopamine system, we hypothesise that: 1) positive symptoms at FEP are more common among psychotic patients who used cannabis compared with never users; 2) this association is a dose-response relationship. Methods: We analyzed a sample o…

FIRST EPISODE PSYCHOSIS PATIENTS ACROSS EUROPE DIFFER IN INTELLECTUAL QUOTIENT (IQ) AND EXPOSURE TO ENVIRONMENTAL HAZARDS

2018

Background Children who later develop Schizophrenia on average are more likely to present with lower IQ; this has been considered evidence for the neurodevelopmental theory of schizophrenia. Though, recent studies have shown that first episode psychosis patients with a history of cannabis use have significantly higher premorbid and current IQ compared to those who never used it. This suggests that abnormal early neurodevelopment does not explain the aetiology of all cases of Schizophrenia, leaving space to environmental hazards. The present study aims to: investigate differences in IQ, as a marker of neurodevelopment, and in exposure to environmental risk factors in a large sample first epi…

The influence of risk factors on the onset and outcome of psychosis: What we learned from the GAP study

2020

The GAP multidisciplinary study carried out in South London, recruited 410 first episode of psychosis patients and 370 controls; the aim was to elucidate the multiple genetic and environmental factors influencing the onset and outcome of psychosis. The study demonstrated the risk increasing effect of adversity in childhood (especially parental loss, abuse, and bullying) on onset of psychosis especially positive symptoms. Adverse life events more proximal to onset, being from an ethnic minority, and cannabis use also played important roles; indeed, one quarter of new cases of psychosis could be attributed to use of high potency cannabis. The “jumping to conclusions” bias appeared to mediate …

IS THE ERA OF CANDIDATE GENES X CANNABIS USE REALLY DEAD?

2019

Background: Historically, gene X environment examinations in psychotic disorders have employed candidate gene methods and environmental determinants impacting on similar biological mechanisms. However, genome wide association studies (GWAS) show that many variants associated with schizophrenia have a modest effect size on risk. In this respect, it is unclear whether the effect of cannabis on psychosis phenotypes is modified by a few genes, e.g. those involved in dopamine signalling, or by the overall genetic susceptibility to schizophrenia. Indeed, candidate gene approaches might be complementary to GWAS to test gene X cannabis interaction. We aimed to investigate the interactive effects of…

Duration of untreated psychosis in first-episode psychosis is not associated with common genetic variants for major psychiatric conditions: results f…

2021

The EU-GEI Project is funded by the European Community’s Seventh Framework Programme under grant agreement No. HEALTH-F2-2010–241909 (Project EU-GEI).

Childhood Maltreatment, Educational Attainment, and IQ: Findings From a Multicentric Case-control Study of First-episode Psychosis (EU-GEI).

2022

[Background and hypothesis] Evidence suggests that childhood maltreatment (ie, childhood abuse and childhood neglect) affects educational attainment and cognition. However, the association between childhood maltreatment and Intelligence Quotient (IQ) seems stronger among controls compared to people with psychosis. We hypothesised that: the association between childhood maltreatment and poor cognition would be stronger among community controls than among people with first-episode of psychosis (FEP); compared to abuse, neglect would show stronger associations with educational attainment and cognition; the association between childhood maltreatment and IQ would be partially accounted for by ot…

T42. JUMPING TO CONCLUSIONS IS ASSOCIATED WITH THE POLYGENIC RISK SCORE FOR INTELLIGENCE BUT NOT FOR SCHIZOPHRENIA. PRELIMINARY FINDINGS FROM THE EU-…

2019

Background Psychotic patients tend to require less evidence to make decisions compared to general population. This bias named Jumping to Conclusions (JTC) has been found at First Episode Psychosis (FEP) in schizophrenia patients and associated with proneness to psychotic-like experiences in the general population. Interesting findings showed also strong association with lower cognitive functioning in psychotic patients, which in turn has been shown as a candidate intermediate phenotype for psychosis. Overall, findings to date could suggest a shared genetic liability between the occurrence of JTC and psychosis, potentially via IQ. The present study aims to investigate whether the presence of…

Substance use, medication adherence and outcome one year following a first episode of psychosis

2016

Both substance use and poor medication adherence are associated with poor outcome in psychosis. To clarify the contributions of substance use and poor medication adherence to poor outcome in the year following a first episode of psychosis, 205 patients were evaluated for use of tobacco, alcohol, cannabis and stimulants at their psychosis onset, and in a 1-year follow-up. Data on medication adherence and symptom remission were also collected. Patients had high rates of overall substance use before (37-65%) and after psychosis onset (45-66%). 44% showed poor medication adherence and 55% did not reach remission from psychosis. Nicotine dependence and cannabis use after psychosis onset signific…

The relationship of symptom dimensions with premorbid adjustment and cognitive characteristics at first episode psychosis: Findings from the EU-GEI s…

2021

Premorbid functioning and cognitive measures may reflect gradients of developmental impairment across diagnostic categories in psychosis. In this study, we sought to examine the associations of current cognition and premorbid adjustment with symptom dimensions in a large first episode psychosis (FEP) sample. We used data from the international EU-GEI study. Bifactor modelling of the Operational Criteria in Studies of Psychotic Illness (OPCRIT) ratings provided general and specific symptom dimension scores. Premorbid Adjustment Scale estimated premorbid social (PSF) and academic adjustment (PAF), and WAIS-brief version measured IQ. A MANCOVA model examined the relationship between symptom di…

O12.4. SOME OF THE INDIVIDUAL DIFFERENCES IN RISK TO DEVELOP PSYCHOSIS AMONG CANNABIS USERS CAN BE EXPLAINED BY WHERE THEY LIVE AND BY THEIR AGE AT F…

2018

Abstract Background Cannabis use remains the most widely used recreational drug worldwide. Following from several USA states legalisation policies, European countries are reconsidering their cannabis laws. While a significant amount of Epidemiological evidence has reported that cannabis use increases the risk of psychosis it is still unclear: 1) what underpins individual differences in developing a psychotic disorder following cannabis use; 2) if variations in availability of cannabis have affected rate of Psychotic disorders across Europe. Methods Using detailed data on lifetime pattern of cannabis use from the EUGEI first episode case-control study (N=2300) and the available Incidence rat…

IQ differences between patients with first episode psychosis in London and Palermo reflect differences in patterns of cannabis use.

2019

Aims: Cognitive impairment is a possible indicator of neurodevelopmental impairment, but not all psychotic patients are cognitively compromised. It has been suggested that heavy cannabis use may precipitate psychosis in those who show no such compromise. This study compares two samples of patients with first-episode psychosis and their respective non-psychotic controls, in London (UK) and Palermo (Italy), and examines whether different patterns of cannabis use are reflected in differences in IQ. Methods: The two studies used the same inclusion/exclusion criteria and instruments. The sample comprised 249 subjects from London (106 patients and 143 controls) and 247 subjects from Palermo (120 …

S118. TRANSDIAGNOSTIC SYMPTOM DIMENSIONS OF PSYCHOSIS AND THE PREDICTIVE ROLE OF PREMORBID ADJUSTMENT AND COGNITIVE CHARACTERISTICS IN THE MULTINATIO…

2020

Abstract Background A symptom dimension approach may best examine the heterogeneous expression of psychosis. However, whether and how premorbid predisposition and cognitive factors explain phenotypes variation is still debated. This study aimed to test the predictive value of combined cognition and premorbid adjustment on transdiagnostic symptom dimensions in a large sample of people suffering from the first episode of psychosis (FEP). Methods FEP patients were part of the EUGEI study. Psychopathology was rated using the OPerational CRITeria system. Multidimensional item response modelling estimate a bifactor model of psychosis by Mplus, composed of a general factor and five specific sympto…

F99. FIRST EPISODE PSYCHOSIS PATIENTS WHO USED CANNABIS DEVELOP THEIR ILLNESS AT A SIGNIFICANTLY YOUNGER AGE THAN THOSE WHO NEVER USED CONSISTENTLY A…

2018

Abstract Background Patients presenting to psychiatric services with their first episode of psychosis (FEP) report higher rates of previous cannabis use than the general population (Donoghue et al., 2011; Myles, Myles and Large, 2016). Evidence suggested that patients suffering from psychosis with a history of cannabis use have an earlier age of onset of psychosis (AOP) than those who never used it (Di Forti et al., 2013). We aim to investigate if the reported association between use of cannabis and AOP is consistent across different countries, once having taken into account different patterns of cannabis use (i.e. frequency of use and age at first use). Methods We analysed data on patterns…

Pre-training inter-rater reliability of clinical instruments in an international psychosis research project.

2021

International audience

Jumping To Conclusions, General Intelligence, And Psychosis Liability: Findings From The Multi-Centre EU-GEI Case-Control Study

2019

AbstractBackgroundThe “jumping to conclusions” (JTC) bias is associated with both psychosis and general cognition but their relationship is unclear. In this study, we set out to clarify the relationship between the JTC bias, IQ, psychosis and polygenic liability to schizophrenia and IQ.Methods817 FEP patients and 1294 population-based controls completed assessments of general intelligence (IQ), and JTC (assessed by the number of beads drawn on the probabilistic reasoning “beads” task) and provided blood or saliva samples from which we extracted DNA and computed polygenic risk scores for IQ and schizophrenia.ResultsThe estimated proportion of the total effect of case/control differences on J…

5.4 BIOLOGICAL AND EPIDEMIOLOGICAL EXAMINATION OF TRANSDIAGNOSTIC AND SPECIFIC SYMPTOM DIMENSIONS AT PSYCHOSIS ONSET: FINDINGS FROM THE EUGEI STUDY

2018

Abstract Background Current diagnostic models of psychosis have been questioned since Kraepelin’s original dichotomy of dementia praecox and manic depression. Indeed, increasing evidence has suggested that a dimensional approach might be a valid alternative platform for research. However, while an increasing number of studies have investigated how environmental risk factors for affective and non-affective psychosis map onto symptom dimensions, only a few have examined these dimensions in relation to genetic variants as summarised by Polygenic Risk Score (PRS). Furthermore, no studies have examined the putative effect of PRS for Schizophrenia (SZ), Bipolar Disorder (BP), and Major Depressive…

Treated Incidence of Psychotic Disorders in the Multinational EU-GEI Study

2018

Importance: Psychotic disorders contribute significantly to the global disease burden, yet the latest international incidence study of psychotic disorders was conducted in the 1980s. Objectives: To estimate the incidence of psychotic disorders using comparable methods across 17 catchment areas in 6 countries and to examine the variance between catchment areas by putative environmental risk factors. Design, Setting, and Participants: An international multisite incidence study (the European Network of National Schizophrenia Networks Studying Gene-Environment Interactions) was conducted from May 1, 2010, to April 1, 2015, among 2774 individuals from England (2 catchment areas), France (3 catch…

The Relationship Between Dissociative Experiences and Cannabis Use: a Systematic Review

2019

Purpose of Review This systematic review aimed to investigate the relation between cannabis use and dissociation. Recent Findings Four analytical and 14 descriptive cross-sectional studies were included. There is no variation in the rates of cannabis use among individuals with dissociative experiences compared with the general population. In addition, the prevalence of dissociative disorders in subjects using cannabis is not different from those not using cannabis. The majority of the studies employed inadequate sampling procedures and a concurrent or retrospective assessment of the two variables, which might have increased the risk of bias, and only a few of them controlled for potential c…

Use of multiple Polygenic Risk Scores for distinguishing Schizophrenia-spectrum disorder and Affective psychosis categories; the EUGEI study

2021

ABSTRACTSchizophrenia (SZ), Bipolar Disorder (BD) and Depression (D) run in families. This susceptibility is partly due to hundreds or thousands of common genetic variants, each conferring a fractional risk. The cumulative effects of the associated variants can be summarised as a polygenic risk score (PRS). Using data from the EUGEI case-control study, we aimed to test whether PRSs for three major psychiatric disorders (SZ, BD, D) and for intelligent quotient (IQ) as a neurodevelopmental proxy, can discriminate affective psychosis (AP) from schizophrenia-spectrum disorder (SSD). Participants (573 cases, 1005 controls) of european ancestry from 17 sites as part of the EUGEI study were succes…

The EUropean Network of National Schizophrenia Networks Studying Gene-Environment Interactions (EU-GEI): Incidence and First-Episode Case-Control Pro…

2020

Purpose: The EUropean Network of National Schizophrenia Networks Studying Gene-Environment Interactions (EU-GEI) study contains an unparalleled wealth of comprehensive data that allows for testing hypotheses about (1) variations in incidence within and between countries, including by urbanicity and minority ethnic groups; and (2) the role of multiple environmental and genetic risk factors, and their interactions, in the development of psychotic disorders. Methods: Between 2010 and 2015, we identified 2774 incident cases of psychotic disorders during 12.9 million person-years at risk, across 17 sites in 6 countries (UK, The Netherlands, France, Spain, Italy, and Brazil). Of the 2774 incident…

O3.1. ASSOCIATION OF EXTENT OF CANNABIS USE AND ACUTE INTOXICATION EXPERIENCES IN A MULTI-NATIONAL SAMPLE OF FIRST EPISODE PSYCHOSIS PATIENTS AND CON…

2019

Background FEP patients who use cannabis experience more frequent intoxication experiences compared to controls. It is not clear whether this is consequent to patients being more vulnerable to the effects of cannabis use or to their heavier pattern of use. We aimed to determine whether extent of use predicted psychotic-like and euphoric intoxication experiences in FEP patients and controls and whether this differs between groups. Methods We analysed data on lifetime cannabis using patients (n=655) and controls (n=654) across 15 sites from six countries in the EU-GEI study (2010–2015). We used multiple regression to model predictors of cannabis-induced experiences and Factorial ANOVA to dete…

Premorbid Adjustment and IQ in Patients With First-Episode Psychosis: A Multisite Case-Control Study of Their Relationship With Cannabis Use

2020

Abstract Psychotic patients with a lifetime history of cannabis use generally show better cognitive functioning than other psychotic patients. Some authors suggest that cannabis-using patients may have been less cognitively impaired and less socially withdrawn in their premorbid life. Using a dataset comprising 948 patients with first-episode psychosis (FEP) and 1313 population controls across 6 countries, we examined the extent to which IQ and both early academic (Academic Factor [AF]) and social adjustment (Social Factor [SF]) are related to the lifetime frequency of cannabis use in both patients and controls. We expected a higher IQ and a better premorbid social adjustment in psychotic p…

O2.1. FIRST EPISODE PSYCHOSIS PATIENTS ACROSS EUROPE DIFFER IN INTELLECTUAL QUOTIENT (IQ) AND EXPOSURE TO ENVIRONMENTAL HAZARDS

2018

Abstract Background Children who later develop Schizophrenia on average are more likely to present with lower IQ; this has been considered evidence for the neurodevelopmental theory of schizophrenia. Though, recent studies have shown that first episode psychosis patients with a history of cannabis use have significantly higher premorbid and current IQ compared to those who never used it. This suggests that abnormal early neurodevelopment does not explain the aetiology of all cases of Schizophrenia, leaving space to environmental hazards. The present study aims to: investigate differences in IQ, as a marker of neurodevelopment, and in exposure to environmental risk factors in a large sample …

FIRST EPISODE PSYCHOSIS PATIENTS WHO USED CANNABIS DEVELOP THEIR ILLNESS AT A SIGNIFICANTLY YOUNGER AGE THAN THOSE WHO NEVER USED CONSISTENTLY ACROSS…

2018

Background: Patients presenting to psychiatric services with their first episode of psychosis (FEP) report higher rates of previous cannabis use than the general population (Donoghue et al., 2011; Myles, Myles and Large, 2016). Evidence suggested that patients suffering from psychosis with a history of cannabis use have an earlier age of onset of psychosis (AOP) than those who never used it (Di Forti et al., 2013). We aim to investigate if the reported association between use of cannabis and AOP is consistent across different countries, once having taken into account different patterns of cannabis use (i.e. frequency of use and age at first use). Methods: We analysed data on patterns of lif…

The independent and combined influence of schizophrenia polygenic risk score and heavy cannabis use on risk for psychotic disorder: A case-control an…

2019

Background: Some recent studies have challenged the direction of causality for the association between cannabis use and psychotic disorder, suggesting that cannabis use initiation is explained by common genetic variants associated with risk of schizophrenia. We used data from the European Union Gene-Environment Interaction consortium (EUGEI) case-control study to test for the independent and combined effect of heavy cannabis use, and of Schizophrenia Polygenic risk score (SZ PRS), on risk for psychotic disorder. Methods: Genome-wide data were obtained from 492 first episode psychosis patients (FEPp) and from 787 controls of European Ancestry, and used to generate SZ PRS from the summary res…

SOME OF THE INDIVIDUAL DIFFERENCES IN RISK TO DEVELOP PSYCHOSIS AMONG CANNABIS USERS CAN BE EXPLAINED BY WHERE THEY LIVE AND BY THEIR AGE AT FIRST USE

2018

Background Cannabis use remains the most widely used recreational drug worldwide. Following from several USA states legalisation policies, European countries are reconsidering their cannabis laws. While a significant amount of Epidemiological evidence has reported that cannabis use increases the risk of psychosis it is still unclear: 1) what underpins individual differences in developing a psychotic disorder following cannabis use; 2) if variations in availability of cannabis have affected rate of Psychotic disorders across Europe. Methods Using detailed data on lifetime pattern of cannabis use from the EUGEI first episode case-control study (N=2300) and the available Incidence rates of Psy…

188. Does Cannabis Use Worsen Psychotic Symptom Presentation?

2017

Background: While the relationship between cannabis and psychosis is well established, there is a lack of studies into whether cannabis use is associated with a particular pattern of symptoms at psychosis onset. Moreover, there is much evidence that psychotic experiences are common in the healthy population, and again their relationship with exposure to cannabis has been scarcely studied. We hypothesized that psychopathology in first-episode psychosis patients (FEP), and psychotic experiences in controls, would be qualitatively and quantitatively affected by pattern of cannabis use.

TRANSDIAGNOSTIC SYMPTOM DIMENSIONS OF PSYCHOSIS AND THE PREDICTIVE ROLE OF PREMORBID ADJUSTMENT AND COGNITIVE CHARACTERISTICS IN THE MULTINATIONAL EU…

2020

Jumping to conclusions, general intelligence, and psychosis liability: Findings from the multi-centre EU-GEI case-control study

2021

This study was funded by the Medical Research Council, the European Community’s Seventh Framework Program grant [agreement HEALTH-F2-2009-241909 (Project EU-GEI)], São Paulo Research Foundation (grant 2012/0417-0), the National Institute for Health Research (NIHR) Biomedical Research Centre (BRC) at South London and Maudsley NHS Foundation Trust and King’s College London, the NIHR BRC at University College London and the Wellcome Trust (grant 101272/Z/12/Z).

Social disadvantage, linguistic distance, ethnic minority status and first-episode psychosis: Results from the EU-GEI case-control study

2021

The European Network of National Schizophrenia Networks Studying Gene-Environment Interactions (EU-GEI) Project was funded by grant agreement Health-F2-2010-241909 (Project EU-GEI) from the European Community’s Seventh Framework programme. The Brazilian study was funded by grant 2012-0417-0 from the São Paulo Research Foundation. Dr Jongsma is funded by the Economic and Social Research Council (grant ES/S011714/1). Dr Kirkbride is funded by the Wellcome Trust and Royal Society (Grant 101272/Z/13/Z). Dr Jongsma and Professor Jones are funded by the National Institute of Health Research Collaboration of Leadership in Applied Health Research and Care East of England. Professor Rutten is funded…

Early Parental Death and Risk of Psychosis in Offspring: A Six-Country Case-Control Study

2019

Evidence for early parental death as a risk factor for psychosis in offspring is inconclusive. We analyzed data from a six-country, case-control study to examine the associations of early parental death, type of death (maternal, paternal, both), and child’s age at death with psychosis, both overall and by ethnic group. In fully adjusted multivariable mixed-effects logistic regression models, experiencing early parental death was associated with 1.54-fold greater odds of psychosis (95% confidence interval (CI): 1.23, 1.92). Experiencing maternal death had 2.27-fold greater odds (95% CI: 1.18, 4.37), paternal death had 1.14-fold greater odds (95% CI: 0.79, 1.64), and both deaths had 4.4…

Facial Emotion Recognition in Psychosis and Associations With Polygenic Risk for Schizophrenia

2022

The EU-GEI Project was funded by the European Community’s Seventh Framework Programme under grant agreement No. HEALTH-F2-2010-241909 (Project EU-GEI). The Brazilian study was funded by the Säo Paulo Research Foundation under grant number 2012/0417-0.

S126. THE RELATION OF THE PSYCHOSIS CONTINUUM WITH SCHIZOPHRENIA POLYGENIC RISK SCORE AND CANNABIS USE

2020

Abstract Background There has been much debate about whether research into psychosis should be conducted using symptom dimensions as opposed to diagnostic categories. Indeed, dimensions, like categories, may be practical but arbitrary tools for research and clinical practice; hence, they should not be based on psychometric data only. The aim of this study was to externally validate empirically derived symptom dimensions using combined genetic and environmental data. Specifically, we examined the hypothesis that the continuous multivariate distribution of psychosis is a function of cannabis use and genetic liability to schizophrenia, as summarised by polygenic risk score (SZ-PRS). Methods As…

Cannabis-associated symptom profiles in patients with first episode psychosis and population controls

2019

AbstractObjectiveThe evidence is mixed on whether cannabis use is associated with a particular symptomatology in first episode psychosis (FEP) patients.The authors set out to investigate a) patterns of association between cannabis use and transdiagnostic symptom dimensions; b) whether the extent of use of cannabis contributes to the variation in clinical and subclinical symptom profiles.MethodThe authors analysed data from 901 patients and 1235 controls recruited across six countries, as part of the European Network of National Schizophrenia Networks Studying Gene-Environment Interactions (EU-GEI) study. Item response modelling was used to estimate two bifactor models, which included genera…

Use of multiple polygenic risk scores for distinguishing schizophrenia-spectrum disorder and affective psychosis categories in a first-episode sample…

2022

This work was supported by funding from the European Community’s Seventh Framework Programme under grant agreement No. HEALTH-F2-2010-241909 (Project EU-GEI). (...) CA was supported by the Spanish Ministry of Science and Innovation; Instituto de Salud Carlos III (SAM16PE07CP1, PI16/02012, PI19/024), co-financed by ERDF Funds from the European Commission, ‘A way of making Europe’, CIBERSAM. Madrid Regional Government (B2017/BMD-3740 AGES-CM-2), Fundación Familia Alonso and Fundación Alicia Koplowitz. MB was supported by the Ministry of Economy and Competitivity (PI08/0208; PI11/00325; PI14/00612), Instituto de Salud Carlos III – ERDF Funds from the European Commission, ‘A way of making Europ…

JUMPING TO CONCLUSIONS AND FACIAL EMOTION RECOGNITION IMPAIRMENT IN FIRST EPISODE PSYCHOSIS ACROSS EUROPE

2018

Background Jumping to conclusions (JTC) is a well-established reasoning and data gathering bias found in patients with psychosis even at illness onset (First Episode Psychosis, FEP). Preliminary work in this field focused primarily on the association with delusions, although jumping to conclusions has also been found in non-deluded schizophrenia patients after remission, and in individual with at risk mental state. Moreover, psychotic patients tend to show impairments in social cognition, struggling in identifying, processing and interpreting social clues. Deficits in facial emotion recognition (FER) – a key component of the construct – represent a well-replicated finding in schizophrenia. …

The Independent Effects of Psychosocial Stressors on Subclinical Psychosis: Findings from the Multinational EU-GEI Study

2021

The influence of psychosocial stressors on psychosis risk has usually been studied in isolation and after the onset of the disorder, potentially ignoring important confounding relationships or the fact that some stressors that may be the consequence of the disorder rather than preexisting. The study of subclinical psychosis could help to address some of these issues. In this study, we investigated whether there was (i) an association between dimensions of subclinical psychosis and several psychosocial stressors including: childhood trauma, self-reported discrimination experiences, low social capital, and stressful life experiences, and (ii) any evidence of environment-environment (ExE) inte…

T52. COGNITION, METACOGNITION AND SOCIAL COGNITION AFTER A FIRST EPISODE PSYCHOSIS. PRELIMINARY RESULTS FROM A 5-YEAR-FOLLOW-UP STUDY

2020

Abstract Background Cognitive impairment is considered a core feature of psychotic disorders. Deficits in cognition, metacognition and social cognition have been reported to be correlated, and indeed predictors, of functional outcome or level of disability. Psychotic patients tend to present lower IQ and show impairment in specific cognitive domains, and in social cognition, than controls. Several studies have found deficits in facial emotion recognition (FER) and a higher prevalence of the jumping to conclusions (JTC) reasoning and data gathering biases among psychotic patients, even at time of illness onset, compared to controls. However, the trajectory of this impairment remains unclear.…

BIOLOGICAL AND EPIDEMIOLOGICAL EXAMINATION OF TRANSDIAGNOSTIC AND SPECIFIC SYMPTOM DIMENSIONS AT PSYCHOSIS ONSET: FINDINGS FROM THE EUGEI STUDY

2018

Background Current diagnostic models of psychosis have been questioned since Kraepelin’s original dichotomy of dementia praecox and manic depression. Indeed, increasing evidence has suggested that a dimensional approach might be a valid alternative platform for research. However, while an increasing number of studies have investigated how environmental risk factors for affective and non-affective psychosis map onto symptom dimensions, only a few have examined these dimensions in relation to genetic variants as summarised by Polygenic Risk Score (PRS). Furthermore, no studies have examined the putative effect of PRS for Schizophrenia (SZ), Bipolar Disorder (BP), and Major Depressive Disorder…

The incidence of psychotic disorders among migrants and minority ethnic groups in Europe: findings from the multinational EU-GEI study

2022

AbstractBackgroundIn Europe, the incidence of psychotic disorder is high in certain migrant and minority ethnic groups (hence: ‘minorities’). However, it is unknown how the incidence pattern for these groups varies within this continent. Our objective was to compare, across sites in France, Italy, Spain, the UK and the Netherlands, the incidence rates for minorities and the incidence rate ratios (IRRs, minorities v. the local reference population).MethodsThe European Network of National Schizophrenia Networks Studying Gene–Environment Interactions (EU-GEI) study was conducted between 2010 and 2015. We analyzed data on incident cases of non-organic psychosis (International Classification of …

The contribution of cannabis use to variation in the incidence of psychotic disorder across Europe (EU-GEI): a multicentre case-control study.

2019

Background: Cannabis use is associated with increased risk of later psychotic disorder but whether it affects incidence of the disorder remains unclear. We aimed to identify patterns of cannabis use with the strongest effect on odds of psychotic disorder across Europe and explore whether differences in such patterns contribute to variations in the incidence rates of psychotic disorder. Methods: We included patients aged 18–64 years who presented to psychiatric services in 11 sites across Europe and Brazil with first-episode psychosis and recruited controls representative of the local populations. We applied adjusted logistic regression models to the data to estimate which patterns of canna…

DOES POLYGENIC RISK SCORE FOR SCHIZOPHRENIA IMPACT ON JUMPING TO CONCLUSIONS? PRELIMINARY FINDINGS FROM THE EU-GEI CASE-CONTROL STUDY

2019

Background: Jumping to conclusions (JTC) is a reasoning and data gathering bias that results in the tendency to require less evidence and make hasty decisions. Preliminary work on reasoning bias focused primarily on the association with delusions, although jumping to conclusions has also been found in non-deluded schizophrenia (SZ) patients. Literature to date has shown JTC as a well-established bias in psychosis even at First Episode Psychosis (FEP), after remission, and in individuals with at risk mental state. Furthermore, JTC has been found to be associated with proneness to psychotic-like experiences in the general population. In teresting findings showed also an association with lower…

F115POLYGENIC RISK SCORES FOR SCHIZOPHRENIA, BIPOLAR, AND MAJOR DEPRESSIVE DISORDERS PREDICT TRANSDIAGNOSTIC SYMPTOM DIMENSIONS AT FIRST EPISODE PSYC…

2019

Background: The value of the nosological distinction between non-affective and affective psychosis has consistently been challenged. Indeed, psychotic syndromes are composed of dimensions of psychopathology cutting across diagnostic boundaries. Such transdiagnostic symptom dimensions might be enhanced phenotypes to test for association with common genetic variants for Major Mental Disorders (MMDs) as summarized by Polygenic Risk Scores (PRSs) for Schizophrenia (SZ), Bipolar Disorder (BP), and Major Depressive Disorder (MDD). The objectives of this study were to: 1) identify the symptom dimension structure at First Episode Psychosis (FEP); 2) examine the extent to which MMDs PRSs explain the…

The continuity of effect of schizophrenia polygenic risk score and patterns of cannabis use on transdiagnostic symptom dimensions at first-episode ps…

2021

The work was supported by Guarantors of Brain post-doctoral clinical fellowship to DQ; Clinician Scientist Medical Research Council fellowship (project reference MR/M008436/1) to MDF; Heisenberg professorship from the German Research Founda- tion (grant no. 389624707) to UR; the National Institute for Health Research (NIHR) Maudsley Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King’s College London. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care. The EU-GEI Project is funded by the European Community’s Seventh Framework Programme under grant agreement No. HEALTH-F2-…