Exposotypes in Psychotic Disorders.

Genetic liability for schizophrenia has been associated with cognitive deficits and clinical phenotypes during neurodevelopment. However, the possible role of executive function (EF) as a mediator between the polygenic risk score for schizophrenia (PRS-SZ) and subsequent outcomes, including transdiagnostic general psychopathology (the p-factor), has yet to be examined. In this study, we investigated whether EF mediates the effect of PRS-SZ on psychopathology and functional phenotypes in a community-based youth sample. We analyzed cross-sectional data from 698 participants (aged 6-14) of the Brazilian High-Risk Cohort. PRS-SZ was calculated using summary statistics from the Psychiatric Genetics Consortium (PGC-3). EF was assessed through working memory, inhibitory control, and time processing tasks, condensed into a single latent EF trait. Independent linear models were tested to examine direct associations between PRS-SZ and EF, general psychopathology, anxiety symptoms, psychotic experiences (PE), and school performance. Mediation models were applied to evaluate EF as a mediator of the associations between PRS-SZ and each outcome. PRS-SZ predicted lower EF scores (β=-0.091, t=-2.435, p=0.015). No direct associations were found between PRS-SZ and the other measures. EF mediated the association between PRS-SZ and general psychopathology (p-factor) (Effect=0.0079, BootSE=0.0049, LLCI=0.0004, ULCI=0.0191), anxiety symptoms (Effect=0.0075, BootSE=0.0047, LLCI=0.0001, ULCI=0.0182), and school performance (Effect=-0.0167, BootSE=0.0077, LLCI=-0.0327, ULCI=-0.0028), but not PE. PRS-SZ was associated with poorer EF, which in turn mediated its associations with increased general psychopathology (p-factor) and anxiety symptoms, and reduced school performance in this community youth sample. EF may represent a hub through which PRS-SZ contributes to negative behavioral and functional outcomes.

Evocative gene-environment correlation between genetic risk for schizophrenia and bullying victimization.

In this presentation, I will explore how the exposome paradigm can be leveraged to advance clinical practice in psychiatry. Specifically, I will highlight the potential of cumulative environmental risk scores to predict outcomes in severe mental disorders, such as the exposome score for schizophrenia (ES-SCZ).Numerous socio-environmental factors have been linked to mental disorders, including childhood adversities, stressful life events, substance use, obstetric complications during pregnancy and childbirth, and urban living. Environmental factors do not exist in isolation; they form complex networks of interrelated and interactive elements. In this regard, the exposome represents the totality of an individual’s environmental exposures throughout their lifetime. The exposome framework introduces a holistic approach to embrace this complexity and a theoretical framework to investigate the poly-gene and poly-environment etiology of psychiatric disorders.Guided by the exposome framework, we have recently estimated the ES-SCZ, a cumulative environmental exposure score for schizophrenia, including cannabis use, winter-birth, hearing impairment, bullying, and five domains of childhood adversities (emotional and physical neglect, along with emotional, sexual, and physical abuse). The ES-SCZ successfully differentiated individuals with schizophrenia, accounting for 28% of the variance in an independent case-control sample. Subsequently, we have tested the risk stratification properties and the predictive performance of the exposome score for schizophrenia in the general population. The ES-SCZ had strong discriminative performance for schizophrenia (AUC = 0.84) and was associated with the degree of psychosis risk in the general population. Finally, we tested the performance of ES-SCZ for dissecting the functional and symptomatic outcome heterogeneity in patients with psychosis in four different cohorts (EUGEI, GROUP, Athens FEP, and HAMLETT-OPHELIA). ES-SCZ was associated with poor overall functioning and cognitive impairment at baseline and follow-up visits. ES-SCZ was also temporally associated with poor symptomatic improvement from baseline to follow-up assessments, particularly the negative symptom dimension. Furthermore, models that included the polygenic risk score for schizophrenia and clinical features showed that the relationship between ES-SCZ and functional outcomes cannot be explained by genetic or clinical risk factors alone.Overall, our findings demonstrate the potential benefits of the exposome score for schizophrenia, which can be integrated for early detection, outcome prognostication, clinical staging, and risk stratification in the future.Disclosure of InterestNone Declared

Individuals with schizophrenia and bipolar disorder are at an increased risk of cardiovascular disease (CVD), and a range of biomarkers related to CVD risk have been found to be abnormal in these patients. Common genetic factors are a putative underlying mechanism, alongside lifestyle factors and antipsychotic medication. However, the extent to which the altered CVD biomarkers are related to genetic factors involved in schizophrenia and bipolar disorder is unknown. In a sample including 699 patients with schizophrenia, 391 with bipolar disorder, and 822 healthy controls, we evaluated 8 CVD risk biomarkers, including BMI, and fasting plasma levels of CVD biomarkers from a subsample. Polygenic risk scores (PGRS) were obtained from genome-wide associations studies (GWAS) of schizophrenia and bipolar disorder from the Psychiatric Genomics Consortium. The CVD biomarkers were used as outcome variables in linear regression models including schizophrenia and bipolar disorder PGRS as predictors, age, sex, diagnostic category, batch and 10 principal components as covariates, controlling for multiple testing by Bonferroni correction for the number of independent tests. Bipolar disorder PGRS was significantly (p = 0.03) negatively associated with BMI after multiple testing correction, and schizophrenia PGRS was nominally negatively associated with BMI. There were no other significant associations between bipolar or schizophrenia PGRS, and other investigated CVD biomarkers. Despite a range of abnormal CVD risk biomarkers in psychotic disorders, we only found a significant negative association between bipolar disorder PGRS and BMI. This has previously been shown for schizophrenia PGRS and BMI, and warrants further exploration.

BackgroundThe genetic etiology of schizophrenia (SCZ) overlaps with that of other major psychiatric disorders in samples of European ancestry. On the other hand, these major psychiatric disorders are distinct diagnoses that have disorder-specific genetic factors. Recently, the bipolar disorder (BIP) and SCZ Working Group of the PGC identified two genome-wide significant loci differentiating the two disorders in individuals of European descent. We hypothesized that genetic variants differentiating SCZ from BIP in Europeans as well as genetic variants related to psychiatric disorders in Europeans would overlap with genetic risk variants in Japanese SCZ patients and unaffected first-degree relatives (FRs), i.e., individuals at high risk of developing SCZ. The present study investigated transethnic polygenetic features shared between Japanese SCZ or their unaffected FRs and European patients with major psychiatric disorders by conducting polygenic risk score (PRS) analyses.MethodsTo calculate PRSs for five psychiatric disorders [SCZ, BIP, major depressive disorder (MDD), autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD)] and PRSs differentiating SCZ from BIP, we utilized large-scale European genome-wide association study (GWAS) datasets as discovery samples. PRSs derived from these GWASs were calculated for 335 Japanese target subjects [131 SCZ patients, 57 of their unaffected FRs and 147 healthy controls (HCs)]. We took these PRSs based on GWASs of European psychiatric disorders (SCZ, BIP, SCZ vs BIP, MDD, ASD and ADHD) and investigated their effect on risk in Japanese SCZ patients [(i) SCZ vs FRs vs HCs, (ii) SCZ vs HCs and (iii) SCZ vs FRs] or unaffected FRs [(iv) FRs vs HCs] by PRS analyses.ResultsThe PRSs obtained from European SCZ samples were significantly higher in Japanese patients with SCZ than in HCs [(i) SCZ vs FRs vs HCs, a maximum at PT≤1.0: adjusted R2=0.028, p=1.30×10–3; (ii) SCZ vs HCs, a maximum at PT≤1.0: Nagelkerke’s R2=0.049, p=1.66×10–3]. In addition, the PRSs related to European BIP were nominally higher in Japanese patients with SCZ than in HCs [(i) SCZ vs FRs vs HCs, a maximum at PT≤0.5: adjusted R2=0.016, p=0.012; (ii) SCZ vs HCs, a maximum at PT≤0.5: Nagelkerke’s R2=0.029, p=0.015]. Furthermore, PRSs differentiating SCZ patients from European BIP patients were marginally higher in Japanese SCZ patients than in HCs [(i) SCZ vs FRs vs HCs, a maximum at PT≤0.05: adjusted R2=0.010, p=0.043; (ii) SCZ vs HCs, a maximum at PT≤0.05: Nagelkerke’s R2=0.020, p=0.046]. Interestingly, the PRSs obtained from European ASD were marginally lower in Japanese FRs compared with HCs [(iv) FRs vs HCs, a maximum at PT≤0.01: Nagelkerke’s R2=0.045, p=0.013] and patients with SCZ [(iii) SCZ vs FRs, a maximum at PT≤0.2: Nagelkerke’s R2=0.023, p=0.084]. As childhood-onset patients with SCZ have showed higher PRSs for both SCZ and ASD than their unaffected siblings, we further investigated the correlation between age at onset and PRSs for both SCZ and ASD in our SCZ samples. Lower age at onset of SCZ was significantly associated with higher PRSs for ASD (PT≤0.05: beta=-0.20, p=7.13×10–3) but not PRSs for SCZ (p>0.05).DiscussionThese findings suggest that polygenic factors related to European SCZ and BIP and the polygenic components differentiating SCZ from BIP can transethnically contribute to SCZ risk in Japanese people. Furthermore, we suggest that reduced levels of an ASD-related genetic factor in unaffected FRs may help protect against SCZ development.

A history of childhood adversity is associated with psychotic disorder, with an increase in risk according to number or severity of exposures. However, it is not known why only some exposed individuals go on to develop psychosis. One possibility is pre-existing genetic vulnerability. Research on gene-environment interaction in psychosis has primarily focused on candidate genes, although the genetic effects are now known to be polygenic. This pilot study investigated whether the effect of childhood adversity on psychosis is moderated by the polygenic risk score for schizophrenia (PRS). Data were utilised from the Genes and Psychosis (GAP) study set in South London, UK. The GAP sample comprises 285 first-presentation psychosis cases and 256 unaffected controls with information on childhood adversity. We studied only white subjects (80 cases and 110 controls) with PRS data, as the PRS has limited predictive ability in patients of African ancestry. The occurrence of childhood adversity was assessed with the Childhood Experience of Care and Abuse Questionnaire (CECA.Q) and the PRS was based on genome-wide meta-analysis results for schizophrenia from the Psychiatric Genomics Consortium. Higher schizophrenia PRS and childhood adversities each predicted psychosis status. Nevertheless, no evidence was found for interaction as departure from additivity, indicating that the effect of polygenic risk scores on psychosis was not increased in the presence of a history of childhood adversity. These findings are compatible with a multifactorial threshold model in which both genetic liability and exposure to environmental risk contribute independently to the etiology of psychosis.

Background: Bipolar disorder is one of the most prevalent psychiatric conditions in Kenya. Studies conducted outside Kenya show that bipolar disorders and psychotic disorders are interlinked by family relations, while alcohol and substance use disorders are their important comorbidities. This study investigated the prevalence and associated factors of psychotic, alcohol and substance use disorders among first-degree relatives (FDR) of patients with bipolar disorders at a referral hospital in Western Kenya. Methods: This was a cross-sectional quantitative study. Consecutive and Simple random sampling were used, with a sample size of 381. The Mini International Neuropsychiatric Interview (MINI) was used for data collection. The chi-square test measured associations utilizing a 95% confidence interval. Results: The prevalences of psychotic, alcohol and substance use disorders were 23.6%, 13.6%, and 6%, respectively. Employment was significantly associated with psychotic disorder (P=0.038), and relation to the patient was significantly associated with alcohol use disorder (P=0.007) and substance use disorder (P=0.001). Conclusion: Among the relatives of patients with bipolar disorders, there is a high prevalence of psychotic, alcohol and substance use disorders.

Cognitive impairment is a common feature of the major psychotic disorders, with deficits often present in at risk individuals and unaffected first-degree relatives. Previous studies have suggested that polygenic risk scores (PRS) for schizophrenia (SCZ) are associated with cognitive deficits, but there has been little examination of this association in longitudinal datasets, or comparison with other disorders. We used mixed models to study the association between PRS for 4 adult onset psychiatric disorders with cross-sectional cognitive performance and longitudinal cognitive decline in 8616 older adults from the Health and Retirement Study (HRS), followed for an average of 10 years. PRS were computed for SCZ, bipolar disorder (BD), Major Depressive Disorder (MDD), and Alzheimer's disease (ALZ). SCZ PRS associated with decreased cognitive function (z = -3.00, P = .001, ΔR (2) = 0.04%), which was largely driven by an association with impaired attention and orientation (z = -3.33, P = 4.3×10(-4), ΔR (2) = 0.08%). We found no effect of BD or MDD PRS on cognition, in contrast to a robust effect of the APOE4/TOMM40 locus (z = -5.05, P = 2.2×10(-7), ΔR (2) = 0.36%), which was primarily associated with impaired verbal memory (z = -5.15, P = 1.3×10(-7), ΔR (2) = 0.21%). APOE4/TOMM40 locus and the ALZ PRS, but not the PRS for SCZ, were associated with greater cognitive decline. In summary, using a large, representative sample of older adults, we found evidence for different degrees of association between polygenic risk for SCZ and genetic risk factors for ALZ on cognitive function and decline, highlighting potential differences in the pathophysiology of cognitive deficits seen in SCZ and ALZ.

Maternal cocaine use and caregiving status: Group differences in caregiver and infant risk variables

BackgroundSleep problems are common in psychotic disorders and are associated with worse quality of life and disease prognosis. Genome-wide association studies (GWAS) have revealed genetic influences for schizophrenia and sleep, but polygenic scores (PGSs) for sleep traits have not been evaluated systematically in patients with psychotic disorders.MethodsThis study investigated the associations between PGSs for sleep traits (insomnia, PGSINS; sleep duration, PGSSD; short sleep duration, PGSSS; long sleep duration; PGSLS), diurnal preference (eveningness, PGSME), and schizophrenia (PGSSZ) with clinical features of psychotic disorders in the Finnish SUPER study comprising 8,232 patients with psychotic disorders. The measures included self-reported sleep and well-being, cognitive assessments, clozapine use, and functional outcomes. Using FinnGen data of 356,077 individuals, we analyzed the distributions of PGSs in psychotic and bipolar disorders and the general population.ResultsPGSINS associated with more sleep problems and worse well-being (e.g. worse health-related quality of life [β = −0.07, CI = −0.09, −0.05, p < .001]). High PGSSZ is associated with better sleep quality, worse clinical outcomes, and performance in cognitive tests (e.g. more errors in paired-associated learning [β = 0.07, CI = 0.04, 0.09, p < .001]). PGSINS was higher in affective psychotic and bipolar disorders, while PGSSD and PGSME were higher in schizophrenia as compared with individuals with no psychiatric disorders.ConclusionGenetic risks for sleep and diurnal preference vary between non-affective psychosis, affective psychosis, and the general population. The findings in this study emphasize the heterogeneity in genetic etiology of the objective features of disease severity and the more subjective measures related to well-being and self-reported measures of sleep.

IntroductionStudies have reported associations between serum anticholinergic activity (SAA) and decline in cognitive performance, delirium, and functional impairment. The aim of this meta-analysis was to explore and quantify associations between SAA and adverse cognitive and functional outcomes in older people.Materials and MethodsA literature search in Ovid MEDLINE, EMBASE, PsycINFO and IPA from 1946–2014 was completed. The primary outcomes of interest were cognitive and functional adverse outcomes associated with SAA in older people aged 55 years and above. The Cochrane Risk-Bias assessment tool was used to assess bias in randomised controlled trials (RCTs). The Newcastle-Ottawa Scale was used to assess the quality of non-RCTs. Meta-analyses were conducted for RCTs and cohort studies separately. Heterogeneity was assessed using I2 tests.ResultsThe primary electronic literature search identified a total of 1559 records in the 4 different databases. On the basis of full-text analysis, 33 studies that met the inclusion criteria. The review included 4 RCTs, 5 prospective cohort studies, 3 longitudinal cohort studies, 17 cross-sectional studies, and 4 case-control studies. Twenty-four of the retrieved studies examined an association between SAA and cognitive outcomes, 2 studies examined an association with SAA and functional outcomes and 8 studies examined associations between SAA and both cognitive, and functional outcomes. The meta-analysis on 4 RCTs showed no association with higher SAA and cognitive performance (I2 = 89.38%, H2 = 25.53 and p-value = <0.05) however, the pooled data from 4 observational studies showed elevated SAA was associated with reduced cognitive performance (I2 = 0.00%, H2 = 3.37 and p-value = 0.34).ConclusionThis systematic review summarises the limitations of the SAA on predicting cognitive and functional outcomes in older people. SAA measured by receptor bioassay is flawed and its use in older people with multimorbidity and polypharmacy is questionable.

BackgroundSchizophrenia is widely recognized as a neurodevelopmental disorder. Abnormal cortical development in otherwise typically developing children and adolescents may be revealed using polygenic risk scores for schizophrenia (PRS-SCZ). MethodsWe assessed PRS-SCZ and cortical morphometry in typically developing children and adolescents (3–21 years, 46.8% female) using whole-genome genotyping and T1-weighted magnetic resonance imaging (n = 390) from the PING (Pediatric Imaging, Neurocognition, and Genetics) cohort. We contextualized the findings using 1) age-matched transcriptomics, 2) histologically defined cytoarchitectural types and functionally defined networks, and 3) case-control differences of schizophrenia and other major psychiatric disorders derived from meta-analytic data of 6 ENIGMA (Enhancing Neuro Imaging Genetics through Meta Analysis) working groups, including a total of 12,876 patients and 15,670 control participants. ResultsHigher PRS-SCZ was associated with greater cortical thickness, which was most prominent in areas with heightened gene expression of dendrites and synapses. PRS-SCZ–related increases in vertexwise cortical thickness were mainly distributed in association cortical areas, particularly the ventral attention network, while relatively sparing koniocortical type cortex (i.e., primary sensory areas). The large-scale pattern of cortical thickness increases related to PRS-SCZ mirrored the pattern of cortical thinning in schizophrenia and mood-related psychiatric disorders derived from the ENIGMA consortium. Age group models illustrate a possible trajectory from PRS-SCZ–associated cortical thickness increases in early childhood toward thinning in late adolescence, with the latter resembling the adult brain phenotype of schizophrenia. ConclusionsCollectively, combining imaging genetics with multiscale mapping, our work provides novel insight into how genetic risk for schizophrenia affects the cortex early in life.

The aim of this study was to determine whether puberty plays a mediating role in onset of schizophrenia. The hypothesis was that there is an inverse relation between age at puberty (menarche) and age at onset in women. Competent and consenting individuals with DSM-IV-defined schizophrenia or schizoaffective disorder and their mothers underwent a 45-minute interview to ascertain age at first odd behavior, age at first psychotic symptoms, age at first hospitalization, and ages at various indices of puberty. Information about substance use, head injury, perinatal trauma, and first-degree family history of schizophrenia was also obtained. In the women (N = 35), the earlier the age at menarche, the later the ages at both the first psychotic symptoms and the first hospitalization. There was no significant association between puberty and onset in the men (N = 45). Other than gender, none of the examined variables played a role in the interaction of puberty and onset of illness. In women, early puberty (whether through hormonal or social influence) was associated with later onset of schizophrenia. This effect was not found in men; in fact, the trend was in the opposite direction.

Childhood trauma, PTSD, and problematic alcohol and substance use in low-income, African-American men and women

Poster #S59 DECREASED GREY MATTER VOLUME AS THE EXPRESSION OF DIFFERENTIAL SENSITIVITY TO ENVIRONMENTAL RISK EXPOSURE IN PSYCHOTIC DISORDER