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Cluster studies identified a subgroup of patients with psychosis whose premorbid adjustment deteriorates before the onset, which may reflect variation in genetic influence. However, other studies reported a complex relationship between distinctive patterns of cannabis use and cognitive and premorbid impairment that is worthy of consideration. We examined whether: (1) premorbid social functioning (PSF) and premorbid academic functioning (PAF) in childhood and adolescence and current intellectual quotient (IQ) define different clusters in 802 first-episode of psychosis (FEP) patients; resulting clusters vary in (2) polygenic risk scores (PRSs) for schizophrenia (SCZ_PRS), bipolar disorder (BD_PRS), major depression (MD_PRS), and IQ (IQ_PRS), and (3) patterns of cannabis use, compared to 1,263 population-based controls. Four transdiagnostic clusters emerged (BIC = 2268.5): (1) high-cognitive-functioning (n = 205), with the highest IQ (Mean = 106.1, 95% CI: 104.3, 107.9) and PAF, but low PSF. (2) Low-cognitive-functioning (n = 223), with the lowest IQ (Mean = 73.9, 95% CI: 72.2, 75.7) and PAF, but normal PSF. (3) Intermediate (n = 224) (Mean_IQ = 80.8, 95% CI: 79.1, 82.5) with low-improving PAF and PSF. 4) Deteriorating (n = 150) (Mean_IQ = 80.6, 95% CI: 78.5, 82.7), with normal-deteriorating PAF and PSF. The PRSs explained 7.9% of between-group membership. FEP had higher SCZ_PRS than controls [F(4,1319) = 20.4, P

The European Community’s Seventh Framework Programme under grant agreement No. HEALTH-F2-2010-241909 (EUGEI); The Spanish sample was supported by the Spanish Ministry of Science and Innovation, Instituto de Salud Carlos III (SAM16PE07CP1, PI16/02012, PI19/024) (...), Velthorst, E., Mollon, J., Murray, R.M., de Haan, L., Germeys, I.M., Glahn, D.C., Arango, C., van der Ven, E., Di Forti, M., Bernardo, M., Guloksuz, S., Delespaul, P., Mezquida, G., Amoretti, S., Bobes, J., Saiz, P.A., García-Portilla, M.P., Santos, J.L., Jiménez-López, E., Sanjuan, J., Aguilar, E.J., Arrojo, M., Carracedo, A., López, G., González-Peñas, J., Parellada, M., Atbaşoğlu, C., Saka, M.C., Üçok, A., Alptekin, K., Akdede, B., Binbay, T., Altınyazar, V., Ulaş, H., Yalınçetin, B., Gümüş-Akay, G., Beyaz, B.C., Soygür, H., Cankurtaran, E.Ş., Kaymak, S.U., Maric, N.P., Mihaljevic, M.M., Petrovic, S.A., Mirjanic, T., Del-Ben, C.M., Ferraro, L., Gayer-Anderson, C., Jones, P.B., Jongsma, H.E., Kirkbride, J.B., La Cascia, C., Lasalvia, A., Tosato, S., Llorca, P.-M., Menezes, P.R., Morgan, C., Quattrone, D., Menchetti, M., Selten, J.-P., Szöke, A., Tarricone, I., Tortelli, A., McGuire, P., Valmaggia, L., Kempton, M.J., van der Gaag, M., Riecher-Rössler, A., Bressan, R.A., Barrantes-Vidal, N., Nelson, B., McGorry, P., Pantelis, C., Krebs, M.-O., Ruhrmann, S., Sachs, G., Rutten, B.P.F., van Os, J., Alizadeh, B.Z., van Amelsvoort, T., Bartels-Velthuis, A.A., Bruggeman, R., van Beveren, N.J., Luykx, J.J., Cahn, W., Simons, C.J.P., Kahn, R.S., Schirmbeck, F., van Winkel, R., Calem, M., Tognin, S., Modinos, G., Pisani, S., Kraan, T.C., van Dam, D.S., Burger, N., Amminger, G.P., Politis, A., Goodall, J., Borgwardt, S., Studerus, E., Gadelha, A., Brietzke, E., Asevedo, G., Asevedo, E., Zugman, A., Domínguez-Martínez, T., Monsonet, M., Cristóbal-Narváez, P., Racioppi, A., Kwapil, T.R., Kazes, M., Daban, C., Bourgin, J., Gay, O., Mam-Lam-Fook, C., Nordholm, D., Rander, L., Krakauer, K., Glenthøj, L.B., Glenthøj, B., Gebhard, D., Arnhold, J., Klosterkötter, J., Lasser, I., Winklbaur, B., Reichenberg, A., EU-GEI High Risk Study

The President of the International Association for the Study of Pain established a task force on cannabis and cannabinoid analgesia to systematically examine the evidence on (1) analgesic pharmacology of cannabinoids and preclinical evidence on their efficacy in animal models of injury-related or pathological persistent pain; (2) the clinical efficacy of cannabis, cannabinoids, and cannabis-based medicines for pain; (3) harms related to long-term use of cannabinoids; as well as (4) societal issues and policy implications related to the use of these compounds for pain management. Here, we summarize key knowledge gaps identified in the task force outputs and propose a research agenda for generating high-quality evidence on the topic. The systematic assessment of preclinical and clinical literature identified gaps in rigor of study design and reporting across the translational spectrum. We provide recommendations to improve the quality, rigor, transparency, and reproducibility of preclinical and clinical research on cannabis and cannabinoids for pain, as well as for the conduct of systematic reviews on the topic. Gaps related to comprehensive understanding of the endocannabinoid system and cannabinoid pharmacology, including pharmacokinetics and drug formulation aspects, are discussed. We outline key areas where high-quality clinical trials with cannabinoids are needed. Remaining important questions about long-term and short-term safety of cannabis and cannabinoids are emphasized. Finally, regulatory, societal, and policy challenges associated with medicinal and nonmedicinal use of cannabis are highlighted, with recommendations for improving patient safety and reducing societal harms in the context of pain management.

BACKGROUND: Ethnic minority groups in Western countries face an increased risk of psychotic disorders. Causes of this long-standing public health inequality remain poorly understood. We investigated whether social disadvantage, linguistic distance and discrimination contributed to these patterns.; METHODS: We used case-control data from the EUropean network of national schizophrenia networks studying Gene-Environment Interactions (EU-GEI) study, carried out in 16 centres in six countries. We recruited 1130 cases and 1497 population-based controls. Our main outcome measure was first-episode ICD-10 psychotic disorder (F20-F33), and exposures were ethnicity (white majority, black, mixed, Asian, North-African, white minority and other), generational status, social disadvantage, linguistic distance and discrimination. Age, sex, paternal age, cannabis use, childhood trauma and parental history of psychosis were included as a priori confounders. Exposures and confounders were added sequentially to multivariable logistic models, following multiple imputation for missing data.; RESULTS: Participants from any ethnic minority background had crude excess odds of psychosis [odds ratio (OR) 2.03, 95% confidence interval (CI) 1.69-2.43], which remained after adjustment for confounders (OR 1.61, 95% CI 1.31-1.98). This was progressively attenuated following further adjustment for social disadvantage (OR 1.52, 95% CI 1.22-1.89) and linguistic distance (OR 1.22, 95% CI 0.95-1.57), a pattern mirrored in several specific ethnic groups. Linguistic distance and social disadvantage had stronger effects for first- and later-generation groups, respectively.; CONCLUSION: Social disadvantage and linguistic distance, two potential markers of sociocultural exclusion, were associated with increased odds of psychotic disorder, and adjusting for these led to equivocal risk between several ethnic minority groups and the white majority.

The work was supported by: Clinician Scientist Medical Research Council fellowship (project reference MR/M008436/1) to MDF; the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care South London at King’s College Hospital NHS Foundation Trust to DQ; DFG Heisenberg professorship (no. 389624707) to UR. National Institute for Health Research (NIHR) Biomedical Research Centre for Mental Health 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-F2-2010-241909 (Project EU-GEI). The Brazilian study was funded by the São Paulo Research Foundation under grant number 2012/0417-0., Quattrone, D., Ferraro, L., Tripoli, G., La Cascia, C., Quigley, H., Quattrone, A., Jongsma, H.E., Del Peschio, S., Gatto, G., Gayer-Anderson, C., Jones, P.B., Kirkbride, J.B., La Barbera, D., Tarricone, I., Berardi, D., Tosato, S., Lasalvia, A., Szöke, A., Arango, C., Bernardo, M., Bobes, J., Del Ben, C.M., Menezes, P.R., Llorca, P.-M., Santos, J.L., Sanjuán, J., Tortelli, A., Velthorst, E., De Haan, L., Rutten, B.P.F., Lynskey, M.T., Freeman, T.P., Sham, P.C., Cardno, A.G., Vassos, E., Van Os, J., Morgan, C., Reininghaus, U., Lewis, C.M., Murray, R.M., Di Forti, M.

Schizophrenia (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 successfully genotyped following standard quality control procedures. Using standardised PRS for SZ, BD, D, and IQ built from the latest available summary statistics, we performed simple or multinomial logistic regression models adjusted for 10 principal components for the different clinical comparisons. In case-control comparisons PRS-SZ, PRS-BD and PRS-D distributed differentially across psychotic subcategories. In case-case comparison, both PRS-SZ (OR=0.7, 95 %CI 0.53-0.92) and PRS-D (OR=1.29, 95%CI 1.05-1.6) differentiated global AP from SSD; and within AP categories, only PRS-SZ differentiated BD from psychotic depression (OR=2.38, 95%CI 1.32-4.29). Combining PRS for severe psychiatric disorders in prediction models for psychosis phenotypes can increase discriminative ability and improve our understanding of these phenotypes. Our results point towards potential usefulness of PRSs for diagnostic prediction in specific populations such as high-risk or early psychosis phases.

Duration of untreated psychosis (DUP) is associated with clinical outcomes in people with a diagnosis of first-episode psychosis (FEP), but factors associated with length of DUP are still poorly understood. Aiming to obtain insights into the possible biological impact on DUP, we report genetic analyses of a large multi-center phenotypically well-defined sample encompassing individuals with a diagnosis of FEP recruited from 6 countries spanning 17 research sites, as part of the European Network of National Schizophrenia Networks Studying Gene-Environment Interactions (EU-GEI) study. Genetic propensity was measured using polygenic scores for schizophrenia (SZ-PGS), bipolar disorder (BD-PGS), major depressive disorder (MDD-PGS), and intelligence (IQ-PGS), which were calculated based on the results from the most recent genome-wide association meta-analyses. Following imputation for missing data and log transformation of DUP to handle skewedness, the association between DUP and polygenic scores (PGS), adjusting for important confounders, was investigated with multivariable linear regression models. The sample comprised 619 individuals with a diagnosis of FEP disorders with a median age at first contact of 29.0 years (interquartile range [IQR] = 22.0-38.0). The median length of DUP in the sample was 10.1 weeks (IQR = 3.8-30.8). One SD increases in SZ-PGS, BD-PGS, MDD-PGS or IQ-PGS were not significantly associated with the length of DUP. Our results suggest that genetic variation does not contribute to the DUP in patients with a diagnosis of FEP disorders. © Crown copyright 2021.

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 cases, 1130 cases were assessed in detail and form the case sample for case-control analyses. Across all sites, 1497 controls were recruited and assessed. We collected data on an extensive range of exposures and outcomes, including demographic, clinical (e.g. premorbid adjustment), social (e.g. childhood and adult adversity, cannabis use, migration, discrimination), cognitive (e.g. IQ, facial affect processing, attributional biases), and biological (DNA via blood sample/cheek swab). We describe the methodology of the study and some descriptive results, including representativeness of the cohort. Conclusions This resource constitutes the largest and most extensive incidence and case-control study of psychosis ever conducted.

BackgroundDiagnostic 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 associations between these dimensions and schizophrenia (SZ) PRSs, as well as the combined effect of SZ-PRS and cannabis use on the positive symptom/experience dimensions.ResultsSZ-PRS was associated with negative (B=0.18; 95%CI 0.03 to 0.34) and positive (B=0.19; 95%CI 0.03 to 0.36) symptom dimensions in 617 FEP, and with all the psychotic experience dimensions in 979 controls. The putative effect of SZ-PRS on either symptom or experience dimensions was of a small magnitude. Cannabis use was additionally associated with the positive dimensions both in FEP (B=0.31; 95%CI 0.11 to 0.52) and in controls (B=0.26; 95%CI 0.06 to 0.46), independently from SZ-PRS.ConclusionsWe report two validators to the latent dimensional structure of psychosis. SZ risk variants and cannabis use independently map onto specific dimensions, contributing to variation across the psychosis continuum. Findings support the hypothesis that psychotic experiences have similar biological substrates as clinical disorders.

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 patients who had ever used cannabis compared to patients without any history of use. We did not expect such differences in controls. In both patients and controls, IQ was 3 points higher among occasional-users than in never-users (mean difference [Mdiff] = 2.9, 95% CI = [1.2, 4.7]). Both cases and control daily-users had lower AF compared to occasional (Mdiff = -0.3, 95% CI = [-0.5; -0.2]) and never-users (Mdiff = -0.4, 95% CI = [-0.6; -0.2]). Finally, patient occasional (Mdiff = 0.3, 95% CI = [0.1; 0.5]) and daily-users (Mdiff = 0.4, 95% CI = [0.2; 0.6]) had better SF than their never-using counterparts. This difference was not present in controls (Fgroup*frequency(2, 2205) = 4.995, P = .007). Our findings suggest that the better premorbid social functioning of FEP with a history of cannabis use may have contributed to their likelihood to begin using cannabis, exposing them to its reported risk-increasing effects for Psychotic Disorders. © The Author(s) 2019. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center.All rights reserved. For permissions, please email: journals.permissions@oup.com.

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 results of an independent meta-analysis. Information on pattern of cannabis use was used to build a 7-level frequency-type composite cannabis use measure that we previously found was a strong predictor of psychotic disorder. Results: SZ PRS did not predict cannabis initiation (b=0.027; p=0.51) or how frequently controls (b=0.027; p=0.06) or FEPp (b=0.006; p=0.91) used it, or the type of cannabis they used (Controls: b = 0.032; p=0.31); FEPp: b= 0.005; p=0.89). The frequency-type composite cannabis use measure (OR=1.32; 95% CI 1.22-1.44) and SZ PRS (OR=2.29; 95%CI 1.71-3.05) showed independent effects from each other on the OR for psychotic disorder. Conclusion: SZ PRS does not predict an individual s propensity to try cannabis, frequency of use, or the potency of the cannabis used. Our findings provide the first evidence that SZ PRS and heavy cannabis use exert effects independent from each other on the risk for psychotic disorder.

People with psychosis have a reduced life expectancy of 10–20 years, largely due to cardiovascular disease. This trial aimed to determine the effectiveness of a modular health promotion intervention (IMPaCT Therapy) in improving health and reducing cardiovascular risk in psychosis. A multicentre, two arm, parallel cluster RCT was conducted across five UK mental health NHS trusts. Community care coordinators (CC) were randomly assigned to training and supervision in delivering IMPaCT Therapy or treatment as usual (TAU) to current patients with psychosis (cluster). The primary outcome was the physical and mental health subscales of the Short form-36 (SF-36) questionnaire. Of 104 care coordinators recruited, 52 (with 213 patients) were randomised to deliver IMPaCT therapy and 52 (with 193 patients) randomised to TAU. Of 406 patients, 318 (78%) and 301 (74%) attended 12- and 15-month follow-up respectively. IMPaCT therapy showed no significant effect on the physical or mental health component SF-36 scores versus TAU at 12 or 15 months. No effect was observed for cardiovascular risk indicators, except for HDL cholesterol, which improved more with IMPACT therapy than TAU (Treatment effect (95% CI); 0.085 (0.007 to 0.16); p = 0.034). The 22% of patients who received >180 min of IMPACT Therapy in addition to usual care achieved a greater reduction in waist circumference than did controls, which was clinically significant. Training and supervising community care coordinators to use IMPaCT therapy in patients with psychosis is insufficient to significantly improve physical or mental health quality of life. The search for effective, pragmatic interventions deliverable in health care services continues. The trial was retrospectively registered with ISRCTN registry on 23/4/2010 at ISRCTN58667926 ; recruitment started on 01/03/2010 with first randomization on 09.08.2010 ISRCTN58667926 .

Aim: Several studies have suggested that lifetime cannabis consumption and childhood abuse synergistically contribute to the risk for psychotic disorders. This study aimed to extend existing findings regarding an additive interaction between childhood abuse and lifetime cannabis use by investigating the moderating role of type and frequency of cannabis use. Methods: Up to 231 individuals presenting for the first time to mental health services with psychotic disorders and 214 unaffected population controls from South London, United Kingdom, were recruited as part of the Genetics and Psychosis study. Information about history of cannabis use was collected using the Cannabis Experiences Questionnaire. Childhood physical and sexual abuse was assessed using the Childhood Experience of Care and Abuse Questionnaire. Results: Neither lifetime cannabis use nor reported exposure to childhood abuse was associated with psychotic disorder when the other environmental variable was taken into account. Although the combination of the two risk factors raised the odds for psychosis by nearly three times (adjusted OR = 2.94, 95% CI: 1.44–6.02, P = 0.003), no evidence of interaction was found (adjusted OR = 1.46, 95% CI: −0.54 to 3.46, P = 0.152). Furthermore, the association of high-potency cannabis and daily consumption with psychosis was at least partially independent of the effect of childhood abuse. Conclusions: The heavy use of high-potency cannabis increases the risk of psychosis but, in addition, smoking of traditional resin (hash) and less than daily cannabis use may increase the risk for psychosis when combined with exposure to severe childhood abuse.

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 work was further funded by: Clinician Scientist Medical Research Council fellowship (project reference MR/M008436/1) to MDF; Veni grant from the Netherlands Organisation for Scientific Research (grant no. 451-13-022) to UR; Sir Henry Dale Fellowship, jointly funded by the Wellcome Trust and the Royal Society (grant no. 101272/Z/13/Z) to JBK; National Institute for Health Research (NIHR) Biomedical Research Centre for Mental Health at South London and Maudsley NHS Foundation Trust and King’s College London. The Brazilian study was funded by the Säo Paulo Research Foundation under grant number 2012/04170., Quattrone, D., Di Forti, M., Gayer-Anderson, C., Ferraro, L., Jongsma, H.E., Tripoli, G., La Cascia, C., La Barbera, D., Tarricone, I., Berardi, D., Szöke, A., Arango, C., Lasalvia, A., Tortelli, A., Llorca, P.-M., De Haan, L., Velthorst, E., Bobes, J., Bernardo, M., Sanjuán, J., Santos, J.L., Arrojo, M., Del-Ben, C.M., Menezes, P.R., Selten, J.-P., Jones, P.B., Kirkbride, J.B., Richards, A.L., O'Donovan, M.C., Sham, P.C., Vassos, E., Rutten, B.P.F., Van Os, J., Morgan, C., Lewis, C.M., Murray, R.M., Reininghaus, U.

Summary Objectives: Cannabis is the most widely used illicit drug globally and its use has been linked to an increased risk for psychotic disorders. An association between cannabis consumption and psychotic symptoms was consistently reported by several studies. This case-control study aimed to widen the current findings about the impact of cannabis exposure on the risk of psychosis, by investigating the pattern of cannabis consumption in a sample of first-episode of psychosis (FEP) patients compared to healthy controls. Material and methods: 68 individuals who presented for the first time to mental health services of Palermo (Italy) with an ICD-10 diagnosis of psychotic disorders and 74 healthy were enrolled as part of the Sicilian Genetics and Psychosis study. Psychopathological assessment and diagnosis were carried out by the Schedule for Clinical Assessment in Neuropsychiatry (SCAN). Socio-demographic data were collected by the modified version of the Medical Research Council (MRC) socio-demographic scale. All participants were interviewed using the Cannabis Experience Questionnaire – Modified Version to obtain a detailed assessment of lifetime patterns of cannabis and other illicit drug consumption. Logistic regression was applied to investigate the relationships between various aspects of cannabis use (lifetime use, age at first use, duration, and frequency of use) and case-control status while controlling for potential confounders. Results: Patients started cannabis consumption about 3 years earlier than the control group (t = 3.1, p = 0.002) and were 8 times more likely to having started using cannabis before 15 years (adjusted OR = 8.0, 95% CI 2.4-27) than controls. Furthermore cases were more likely to smoke more frequently than controls (adjusted OR = 4.4, 95% CI 1.08-18). We did not find a difference in duration of cannabis use between cases and controls. Conclusions: The findings suggest that cannabis exposure, and especially daily cannabis consumption, is associated with the risk for psychosis; however, the retrospective study design does not allow drawing firm conclusions about causality.

Introduction There are strong enough evidences of the fact that risk of psychosis is augmented by cannabis use. In a recent analysis, the strongest predictor of case-control status was daily-skunk use, i.e. the ORs for skunk users increase with the frequency of use5. We know also that FEP who smoked cannabis in their lifetime are less neuropsychologically impaired i.e. they have better premorbid and current IQ6. In this study we wanted to test what augments the probability to be everyday users, taking into account premorbid social and academic adjustment and cognition as predictors, along with age at first cannabis-use and % of THC in cannabis used. Methods The sample was made of 834 First Episode Psychosis (FEP) cannabis-using and non-using patients from different European countries and 1.061 healthy controls, as part of the EUGEI-STUDY. A logistic regression was computed, using frequency of cannabis use among those who reported to have used cannabis in their lifetime, as an outcome variable in order to estimate the risk to be an everyday-user (heavy user) or a less-than-everyday user (recreational user), taking into account a list of predictors: sociodemographics, age at first cannabis-use, % of THC, premorbid social factor (PSF), premorbid academic factor (PAF), extracted from the Premorbid Adjustment Scale (PAS) and the four scales of WAIS-brief version. Results The risk to be an everyday-smoker was higher for cases, in interaction with age at first use, i.e. while the risk of controls diminishes when age at first use increases, this is not true for cases, whose risk stay higher even when age at first use increases (OR=1.2, p=0.001, CI 95% 1.09, 1.45). THC absolute concentration >10% augmented almost 2 folds the risk to be an everyday-smoker (OR=1.8, p=0.001, CI 95% 1.29, 2.60). A lower premorbid academic adjustment (OR=0.8, p=0.040, CI 95% 0.68, 0.99) and higher premorbid social adjustment before 16 years (OR=1.6, p=0.019, CI 95% 1.08, 2.60) increased the risk to be a heavy cannabis user, along with having a lower education level and being unemployed (all p

PURPOSE: Cannabis use is associated with an earlier age of onset of psychosis (AOP). However, the reasons for this remain debated. METHODS: We applied a Cox proportional hazards model to 410 first-episode psychosis patients to investigate the association between gender, patterns of cannabis use, and AOP. RESULTS: Patients with a history of cannabis use presented with their first episode of psychosis at a younger age (mean years = 28.2, SD = 8.0; median years = 27.1) than those who never used cannabis (mean years = 31.4, SD = 9.9; median years = 30.0; hazard ratio [HR] = 1.42; 95% CI: 1.16-1.74; P < .001). This association remained significant after controlling for gender (HR = 1.39; 95% CI: 1.11-1.68; P < .001). Those who had started cannabis at age 15 or younger had an earlier onset of psychosis (mean years = 27.0, SD = 6.2; median years = 26.9) than those who had started after 15 years (mean years = 29.1, SD = 8.5; median years = 27.8; HR = 1.40; 95% CI: 1.06-1.84; P = .050). Importantly, subjects who had been using high-potency cannabis (skunk-type) every day had the earliest onset (mean years = 25.2, SD = 6.3; median years = 24.6) compared to never users among all the groups tested (HR = 1.99; 95% CI: 1.50- 2.65; P < .0001); these daily users of high-potency cannabis had an onset an average of 6 years earlier than that of non-cannabis users. CONCLUSIONS: Daily use, especially of high-potency cannabis, drives the earlier onset of psychosis in cannabis users.

Aim\ud Prisoners exhibit high rates of substance use and mental health problems. In the present study, we sought to gain a detailed understanding of substance use amongst young prisoners to inform early detection and early intervention strategies in a prison setting.\ud \ud Methods\ud This is a cross‐sectional study of 2102 prisoners who were screened by the London Early Detection and Prevention in Prison Team (LEAP). Data on the use of substances were collected including age of first use, recent use, duration of use and poly‐drug use. The Prodromal Questionnaire – Brief Version was used to screen for the at‐risk mental state.\ud \ud Results\ud We found high rates of lifetime and recent use and low age of first use of a number of substances. We also found strong associations between substance use and screening positive for an at‐risk mental state. Logistic regression analysis confirmed that use of any drug in the last year, poly‐drug and early use, as well as heavy alcohol use, were related to an increased risk of screening positive.\ud \ud Conclusions\ud Substance use in the prison population is not only widespread and heavy but is also strongly linked with a higher risk of developing mental health problems. The need for early detection and early intervention in prison is discussed.

BACKGROUND: There is increasing evidence for shared genetic susceptibility between schizophrenia and bipolar disorder. Although genetic variants only convey subtle increases in risk individually, their combination into a polygenic risk score constitutes a strong disease predictor.AimsTo investigate whether schizophrenia and bipolar disorder polygenic risk scores can distinguish people with broadly defined psychosis and their unaffected relatives from controls. METHOD: Using the latest Psychiatric Genomics Consortium data, we calculated schizophrenia and bipolar disorder polygenic risk scores for 1168 people with psychosis, 552 unaffected relatives and 1472 controls. RESULTS: Patients with broadly defined psychosis had dramatic increases in schizophrenia and bipolar polygenic risk scores, as did their relatives, albeit to a lesser degree. However, the accuracy of predictive models was modest. CONCLUSIONS: Although polygenic risk scores are not ready for clinical use, it is hoped that as they are refined they could help towards risk reduction advice and early interventions for psychosis.Declaration of interestR.M.M. has received honoraria for lectures from Janssen, Lundbeck, Lilly, Otsuka and Sunovian. Funding: This work was funded by the Medical Research Council (G0901310), the Wellcome Trust (grants 085475/B/08/Z, 085475/Z/08/Z), the European Union’s Seventh Framework Programme for research, technological development and demonstration (grant 602450). This study was also supported by the NIHR Biomedical Research Centre at University College London (mental health theme) and by the NIHR Biomedical Research Centre at the South London and Maudsley NHS Foundation Trust and Institute of Psychiatry – Kings College London. Further support: NHIR Academic Clinical fellowship awarded to M.S.C.. E.B. acknowledges research funding from: BMA Margaret Temple grants 2016 and 2006, MRC – Korean Health Industry Development Institute Partnering Award (MC_PC_16014), MRC New Investigator Award and a MRC Centenary Award (G0901310), National Institute of Health Research UK post-doctoral fellowship, the Psychiatry Research Trust, the Schizophrenia Research Fund, the Brain and Behaviour Research foundation’s NARSAD Young Investigator Awards 2005, 2008, Wellcome Trust Research Training Fellowship and the NIHR Biomedical Research Centre for Mental Health at the South London and Maudsley NHS Foundation Trust and Institute of Psychiatry Kings College London. The Brain and Behaviour Research foundation’s (NARSAD’s) Young Investigator Award (Grant 22604, awarded to C.I.). The BMA Margaret Temple grant 2016 to J. H.T. European Research Council Marie Curie award to A.D.-R. The infrastructure for the GROUP consortium is funded through the Geestkracht programme of the Dutch Health Research Council (ZON-MW, grant number 10-000-1001), and matching funds from participating pharmaceutical companies (Lundbeck, AstraZeneca, Eli Lilly, Janssen Cilag) and universities and mental healthcare organisations. Amsterdam: Academic Psychiatric Centre of the Academic Medical Center and the mental health institutions: GGZ Ingeest, Arkin, Dijk en Duin, GGZ Rivierduinen, Erasmus Medical Centre, GGZ Noord Holland Noord. Maastricht: Maastricht University Medical Centre and the mental health institutions: GGZ Eindhoven en de kempen, GGZ Breburg, GGZ Oost-Brabant, Vincent van Gogh voor Geestelijke Gezondheid, Mondriaan Zorggroep, Prins Clauscentrum Sittard, RIAGG Roermond, Universitair Centrum Sint-Jozef Kortenberg, CAPRI University of Antwerp, PC Ziekeren Sint-Truiden, PZ Sancta Maria Sint-Truiden, GGZ Overpelt, OPZ Rekem. Groningen: University Medical Center Groningen and the mental health institutions: Lentis, GGZ Friesland, GGZ Drenthe, Dimence, Mediant, GGNet Warnsveld, Yulius Dordrecht and Parnassia psychomedical center (The Hague). Utrecht: University Medical Center Utrecht and the mental health institutions Altrecht, GGZ Centraal, Riagg Amersfoort and Delta. The sample from Spain was collected at the Hospital Universitario Marqués de Valdecilla, University of Cantabria, Santander, Spain, under the following grant support: Carlos III Health Institute PI020499, PI050427, PI060507, Plan Nacional de Drugs Research Grant 2005- Orden sco/3246/2004, SENY Fundació Research Grant CI 2005-0308007 and Fundación Marqués de Valdecilla API07/011. The present data were obtained at the Hospital Marqués de Valdecilla, University of Cantabria, Santander, Spain, under the following grant support: MINECO Exp.: SAF2013-46292-R.

BackgroundA range of endophenotypes characterise psychosis, however there has been limited work understanding if and how they are inter-related.MethodsThis multi-centre study includes 8754 participants: 2212 people with a psychotic disorder, 1487 unaffected relatives of probands, and 5055 healthy controls. We investigated cognition [digit span (N= 3127), block design (N= 5491), and the Rey Auditory Verbal Learning Test (N= 3543)], electrophysiology [P300 amplitude and latency (N= 1102)], and neuroanatomy [lateral ventricular volume (N= 1721)]. We used linear regression to assess the interrelationships between endophenotypes.ResultsThe P300 amplitude and latency were not associated (regression coef. −0.06, 95% CI −0.12 to 0.01,p= 0.060), and P300 amplitude was positively associated with block design (coef. 0.19, 95% CI 0.10–0.28,p< 0.001). There was no evidence of associations between lateral ventricular volume and the other measures (allp> 0.38). All the cognitive endophenotypes were associated with each other in the expected directions (allp< 0.001). Lastly, the relationships between pairs of endophenotypes were consistent in all three participant groups, differing for some of the cognitive pairings only in the strengths of the relationships.ConclusionsThe P300 amplitude and latency are independent endophenotypes; the former indexing spatial visualisation and working memory, and the latter is hypothesised to index basic processing speed. Individuals with psychotic illnesses, their unaffected relatives, and healthy controls all show similar patterns of associations between endophenotypes, endorsing the theory of a continuum of psychosis liability across the population.