Social disorganization of neighborhoods and incidence of psychotic disorders: a 7-year first-contact incidence study

Changing Neighborhood Income Deprivation Over Time, Moving in Childhood, and Adult Risk of Depression

Importance

Complex biological, socioeconomic, and psychological variables combine to cause mental illnesses, with mounting evidence that early-life experiences are associated with adulthood mental health.

Objective

To evaluate whether changing neighborhood income deprivation and residential moves during childhood are associated with the risk of receiving a diagnosis of depression in adulthood.

Design, Setting, and Participants

This cohort study included the whole population of 1 096 916 people born in Denmark from January 1, 1982, to December 31, 2003, who resided in the country during their first 15 years of life. Individuals were followed up from 15 years of age until either death, emigration, depression diagnosis, or December 31, 2018. Longitudinal data on residential location was obtained by linking all individuals to the Danish longitudinal population register. Statistical analysis was performed from June 2022 to January 2024.

Exposures

Exposures included a neighborhood income deprivation index at place of residence for each year from birth to 15 years of age and a mean income deprivation index for the entire childhood (aged ≤15 years). Residential moves were considered by defining "stayers" as individuals who lived in the same data zone during their entire childhood and "movers" as those who did not.

Main Outcomes and Measures

Multilevel survival analysis determined associations between neighborhood-level income deprivation and depression incidence rates after adjustment for individual factors. Results were reported as incidence rate ratios (IRRs) with 95% credible intervals (95% CrIs). The hypotheses were formulated before data collection.

Results

A total of 1 096 916 individuals (563 864 male participants [51.4%]) were followed up from 15 years of age. During follow-up, 35 098 individuals (23 728 female participants [67.6%]) received a diagnosis of depression. People living in deprived areas during childhood had an increased risk of depression (IRR, 1.10 [95% CrI, 1.08-1.12]). After full individual-level adjustment, the risk was attenuated (IRR, 1.02 [95% CrI, 1.01-1.04]), indicating an increase of 2% in depression incidence for each 1-SD increase in income deprivation. Moving during childhood, independent of neighborhood deprivation status, was associated with significantly higher rates of depression in adulthood compared with not moving (IRR, 1.61 [95% CrI, 1.52-1.70] for 2 or more moves after full adjustment).

Conclusions and Relevance

This study suggests that, rather than just high or changing neighborhood income deprivation trajectories in childhood being associated with adulthood depression, a settled home environment in childhood may have a protective association against depression. Policies that enable and support settled childhoods should be promoted.

Bane or boon regarding urbanicity and psychotic spectrum disorders: a scoping review of current evidence

PURPOSE OF REVIEW

This review aims to provide an update on the association between urbanization and psychotic spectrum disorders, focusing on specific aspects of the urban environment that could be a bane or boon for the risk of psychosis.

RECENT FINDINGS

Majority of the included studies support previous evidence suggesting that urbanization is linked to a higher risk of psychotic experiences and psychotic spectrum disorders. A small minority, however, have also found specific factors in the urban environment that could give rise to positive outcomes, such as better social functioning and lower mortality rates in psychotic spectrum disorders, or mitigate the risks associated with urbanization. The perception of the urban environment was also an important factor that increased or mitigated stress levels in patients with psychosis, which in turn affected their susceptibility to psychotic symptoms.

SUMMARY

Specific aspects of the urban environment such as the availability and density of greenspaces are crucial for mitigating the effect of urbanization on risk of psychotic spectrum disorders, and should be incorporated into urban planning. At the same time, there is a need to further explore how modifiable risk factors of the urban environment such as air and noise pollution can be minimized to allow for more liveable cities in the context of psychotic spectrum conditions.

Development and initial validation of a multivariable predictive Early Adversity Scale for Schizophrenia (EAS-Sz) using register data to quantify environmental risk for adult schizophrenia diagnosis after childhood exposure to adversity

BACKGROUND

Additional to a child's genetic inheritance, environmental exposures are associated with schizophrenia. Many are broadly described as childhood adversity; modelling the combined impact of these is complex. We aimed to develop and validate a scale on childhood adversity, independent of genetic and other environmental liabilities, for use in schizophrenia risk analysis models, using data from cross-linked electronic health and social services registers.

METHOD

A cohort of N = 428 970 Western Australian children born 1980-2001 was partitioned into three samples: scale development sample (N = 171 588), and two scale validation samples (each N = 128 691). Measures of adversity were defined before a child's 10th birthday from five domains: discontinuity in parenting, family functioning, family structure, area-level socioeconomic/demographic environment and family-level sociodemographic status. Using Cox proportional hazards modelling of follow-up time from 10th birthday to schizophrenia diagnosis or censorship, weighted combinations of measures were firstly developed into scales for each domain, then combined into a final global scale. Discrimination and calibration performance were validated using Harrell's C and graphical assessment respectively.

RESULTS

A weighted combination of 42 measures of childhood adversity was derived from the development sample. Independent application to identical measures in validation samples produced Harrell's Concordance statistics of 0.656 and 0.624. Average predicted time to diagnosis curves corresponded with 95% CI limits of observed Kaplan-Meier curves in five prognostic categories.

CONCLUSIONS

Our Early Adversity Scale for Schizophrenia (EAS-Sz), the first using routinely collected register data, predicts schizophrenia diagnosis above chance, and has potential to help untangle contributions of genetic and environmental liability to schizophrenia risk.

Review of Major Social Determinants of Health in Schizophrenia-Spectrum Disorders: II. Assessments

BACKGROUND AND AIMS

Social determinants of health (SDoHs) impact the development and course of schizophrenia-spectrum psychotic disorders (SSPDs). Yet, we found no published scholarly reviews of psychometric properties and pragmatic utility of SDoH assessments among people with SSPDs. We aim to review those aspects of SDoH assessments.

STUDY DESIGN

PsychInfo, PubMed, and Google Scholar databases were examined to obtain data on reliability, validity, administration process, strengths, and limitations of the measures for SDoHs identified in a paired scoping review.

STUDY RESULTS

SDoHs were assessed using different approaches including self-reports, interviews, rating scales, and review of public databases. Of the major SDoHs, early-life adversities, social disconnection, racism, social fragmentation, and food insecurity had measures with satisfactory psychometric properties. Internal consistency reliabilities-evaluated in the general population for 13 measures of early-life adversities, social disconnection, racism, social fragmentation, and food insecurity-ranged from poor to excellent (0.68-0.96). The number of items varied from 1 to more than 100 and administration time ranged from less than 5 minutes to over an hour. Measures of urbanicity, low socioeconomic status, immigration status, homelessness/housing instability, and incarceration were based on public records or targeted sampling.

CONCLUSIONS

Although the reported assessments of SDoHs show promise, there is a need to develop and test brief but validated screening measures suitable for clinical application. Novel assessment tools, including objective assessments at individual and community levels utilizing new technology, and sophisticated psychometric evaluations for reliability, validity, and sensitivity to change with effective interventions are recommended, and suggestions for training curricula are offered.

Socioenvironmental Adversity and Adolescent Psychotic Experiences: Exploring Potential Mechanisms in a UK Longitudinal Cohort

BACKGROUND AND HYPOTHESIS

Children exposed to socioenvironmental adversities (eg, urbanicity, pollution, neighborhood deprivation, crime, and family disadvantage) are more likely to subsequently develop subclinical psychotic experiences during adolescence (eg, hearing voices, paranoia). However, the pathways through which this occurs have not been previously investigated. We hypothesized that cognitive ability and inflammation would partly explain this association.

STUDY DESIGN

Data were utilized from the Environmental-Risk Longitudinal Twin Study, a cohort of 2232 children born in 1994-1995 in England and Wales and followed to age 18. Socioenvironmental adversities were measured from birth to age 10 and classified into physical risk (defined by high urbanicity and air pollution) and socioeconomic risk (defined by high neighborhood deprivation, neighborhood disorder, and family disadvantage). Cognitive abilities (overall, crystallized, fluid, and working memory) were assessed at age 12; and inflammatory markers (C-reactive protein, interleukin-6, soluble urokinase plasminogen activator receptor) were measured at age 18 from blood samples. Participants were interviewed at age 18 regarding psychotic experiences.

STUDY RESULTS

Higher physical risk and socioeconomic risk were associated with increased odds of psychotic experiences in adolescence. The largest mediation pathways were from socioeconomic risk via overall cognitive ability and crystallized ability, which accounted for ~11% and ~19% of the association with psychotic experiences, respectively. No statistically significant pathways were found via inflammatory markers in exploratory (partially cross-sectional) analyses.

CONCLUSIONS

Cognitive ability, especially crystallized ability, may partly explain the association between childhood socioenvironmental adversity and adolescent psychotic experiences. Interventions to support cognitive development among children living in disadvantaged settings could buffer them against developing subclinical psychotic phenomena.

The association between social deprivation and the rate of identification of individuals at Ultra-High Risk for psychosis and transition to psychosis

BACKGROUND

There is a higher incidence of psychotic disorders in neighbourhoods of greater social deprivation. However, it is not known whether this represents a causal relationship, as the stage at which social deprivation exerts its influence on the development of psychotic disorders is yet to be elucidated. We aimed to investigate the association between neighbourhood-level social deprivation and the rate of identification of individuals at Ultra-High Risk for psychosis (UHR), as well as the risk of transition to psychosis in UHR individuals.

METHODS

The cohort included all young people aged 15 to 24 identified as UHR attending an Early Intervention clinic in northwestern Melbourne over a 5-year period (2012-2016). Australian census data were used to obtain the at-risk population and social deprivation information according to the postcode of residence. Levels of social deprivation were arranged into quartiles. Poisson regression was used to calculate rate ratios and Cox regression analysis determined hazard ratios.

RESULTS

Of the 461 young people identified as UHR, 11.1% (n = 49) lived in the most affluent neighbourhoods (Quartile 1) compared to 36.7% (n = 162) in the most deprived neighbourhoods (Quartile 4). There was a 35% higher rate of identification of young people who were UHR from the most deprived neighbourhoods (aIRR = 1.35, 95% CI [0.98, 1.86]). Over a median follow-up of approximately 10 months (308 days (IQR: 188-557), 17.5% (n = 77) were known to have transitioned to a full-threshold psychotic disorder. Residing in a neighbourhood of above average deprivation had a hazard ratio of 2.05 (95% CI [0.88, 4.80]) for risk of transition, when controlling for age, sex and substance use.

CONCLUSIONS

These findings provide more support that EI services should be funded as per the expected incidence of psychotic disorders.

Understanding Associations Between Race/Ethnicity, Experiences of Discrimination, and Psychotic-like Experiences in Middle Childhood

OBJECTIVE

The present study aimed to examine factors that may account for race/ethnicity differences in psychotic-like experiences (PLEs) in a middle childhood sample, including evidence for experiences of discrimination as a psychosocial mediator of these differences.

METHOD

In a sample of 9- to 10-year-olds (N = 10,839) from the Adolescent Brain Cognitive Development Study, we compared PLEs across racial/ethnic groups. We also examined whether experiences of discrimination indirectly linked racial/ethnic identity and PLEs and whether social support moderated this indirect association.

RESULTS

Differences between racial/ethnic groups were found in the endorsement of PLEs, such that Black and Hispanic participants endorsed higher levels of PLEs compared with Asian, multiracial/multiethnic, and White participants. These differences were accounted for in part by experiences of discrimination, an indirect effect that was in turn attenuated by increased social support.

CONCLUSION

This is the first study to suggest that the experience of discrimination may indirectly link the association between racial/ethnic differences and endorsement of PLEs using the Prodromal Questionnaire-Brief Child Version and additionally that social support may act as a moderator of this mediation. Results provide evidence that social inequities such as racial discrimination may contribute to increases in PLEs. These findings shed further light on the links between structural racism and mental health inequities for people in minoritized groups.

From scary places to therapeutic landscapes: Voices from the community of people living with schizophrenia

This article discusses how people living with schizophrenia experience, understand, and respond to their urban environment. Our study relies on experiential photo-voice data gathered with a sample of six people diagnosed with schizophrenia and living in non-institutional settings in Montréal, Canada, to identify how individuals in this community perceive the urban landscape. We adopt a therapeutic landscapes' framework that explores the urban fabric at three levels: physical, social, and symbolic. Research participants identified both health-denying and health-enhancing places within ordinary urban landscapes. Landscapes identified as health-denying are characterized by environmental stressors and loss of control, with construction sites an example highlighted by participants. Healing and restorative landscapes, as identified by participants, were physically attractive or quiet, socially safe and welcoming, and symbolically affirmative of one's identity, all factors worthy of further study. The findings are also policy-relevant: they suggest that people living with schizophrenia and their clinicians can develop strategies to make health-enhancing uses of urban landscapes; and that urban policies and practices can foster urban environments conducive to enhanced health and well-being, both for the community of people living with schizophrenia and the wider population of urban dwellers.

First episode of psychosis in Guam: The role of ethnicity and neighbourhood factors

OBJECTIVE

Ethnicity, neighbourhood ethnic density, and four additional neighbourhood factors (urbanicity, crime, voting, and poverty) were examined in relation to the incidence of first episode of psychosis (FEP) in the Pacific Island of Guam.

METHODS

All first contact patients seen at the Guam Department of Mental Health and Substance Abuse (DMHSA) between January 2005 and December 2007 that met DSM-IV criteria for the diagnosis of a psychotic disorder were included. At the time of the study, DMHSA was the only psychiatric facility in Guam.

RESULTS

After controlling for age and gender, Chamorros, the indigenous people of Guam, had a standardized incidence rate (IR = 151/100 000 person-years, 95%CI = 129-173) of FEP over twice that of Whites (IR = 66/100 000 person-years, 95%CI = 34-99). Individuals from Palau had the highest standardized incidence rate (IR = 832/100 000 person-years, 95%CI = 581-1083). Increased neighbourhood Chamorro density was associated with decreased incidence of FEP among Chamorro individuals (IRR = 0.11, 95%CI = 0.03-0.43). After controlling for age, gender, ethnicity, and other neighbourhood factors, urbanicity (IRR = 3.82, 95%CI = 1.86-7.81), voting (IRR = 2.06, 95%CI = 1.32-3.20), poverty (IRR = 1.94, 95%CI = 1.40-2.67), and crime (IRR = 1.18, 95%CI = 1.00-1.40) remained statistically associated with FEP incidence.

CONCLUSIONS

The findings add to prior research that suggests that rates of mental health problems are higher in indigenous than in settler communities and are highest for indigenous people who live in neighbourhoods with few other indigenous individuals. Findings also suggest that even on a small island, with only ~150 000 people, urbanicity is associated with FEP. Finally, results are consistent with other research suggesting that the reduction of crime and social adversity can play a positive role in reducing the incidence of first episode psychosis.

Explaining the Association Between Urbanicity and Psychotic-Like Experiences in Pre-Adolescence: The Indirect Effect of Urban Exposures

Urban living is a growing worldwide phenomenon with more than two-thirds of people expected to live in cities by 2050. Although there are many benefits to living in an urban environment, urbanicity has also been associated with deleterious health outcomes, including increased risk for psychotic outcomes particularly when the urban exposure occurs in pre-adolescence. However, the mechanisms underlying this association is unclear. Here, we utilize one-year follow-up data from a large (N=7,979), nationwide study of pre-adolescence in the United States to clarify why urbanicity (i.e., census-tract population density) might impact psychotic-like experiences (PLE) by looking at the indirect effect of eight candidate urbanicity-related physical (e.g., pollution) and social (e.g., poverty) exposures. Consistent with other work, we found that of the evaluated exposures related to urbanicity, several were also related to increased number of PLE: PM2.5, proximity to roads, census-level homes at-risk for exposure to lead paint, census-level poverty, and census-level income-disparity. These same urban-related exposures were also related to the persistence of PLE after 1 year, but not new onset of PLE. Mediation analysis revealed that a substantial proportion the urbanicity-PLE association (number and persistence) could be explained by PM2.5 (23-44%), families in poverty (68-93%), and income disparity (67-80%). Together, these findings suggest that specific urban-related exposures contribute to the existence and maintenance, but not onset of PLE, which might help to explain why those in urban environments are disproportionately at-risk for psychosis and point toward areas for public health intervention.

Neighbourhood characteristics and social isolation of people with psychosis: a multi-site cross-sectional study

PURPOSE

People with psychosis are vulnerable to social isolation, which is associated with worse clinical outcomes. In general populations, people living in areas with higher population density have more social contacts, while those living in more socially deprived and fragmented areas are less satisfied with their relationships. We assessed whether and how neighbourhood factors are associated with social contacts and satisfaction with friendships for people with psychosis.

METHODS

We carried out a cross-sectional study including people with psychosis aged 18-65 years in urban and rural sites in England. Population density and social deprivation and fragmentation indexes were described within Lower Level Super Output Areas (LSOA). Their associations with participants' social contacts and satisfaction with friendships were tested with negative binomial and ordinal regression models, respectively.

RESULTS

We surveyed 511 participants with psychotic disorders. They had a median of two social contacts in the previous week (interquartile range [IQR] = 1-4), and rated satisfaction with friendships as 5 out of 7 (Manchester Short Assessment of Quality of Life; IQR = 4-6). Higher population density was associated with fewer social contacts (Z-standardised relative risk [RR] = 0.88; 95% CI = 0.79-0.99, p = 0.03), but not with satisfaction with friendships (RR = 1.08; 95% CI = 0.93-1.26, p = 0.31). No associations were found for social contacts or satisfaction with friendships with social deprivation or fragmentation indexes.

CONCLUSIONS

Clinicians in urban areas should be aware that their patients with psychosis are more socially isolated when more people live around them, and this could impact their clinical outcomes. These findings may inform housing programmes.

The impact of neighbourhood crime on mental health: A systematic review and meta-analysis

BACKGROUND

Growing evidence indicates that the residential neighbourhood contributes to the complex aetiology of mental disorders. Although local crime and violence, key neighbourhood stressors, may be linked to mental health through direct and indirect pathways, studies are inconclusive. This systematic review and meta-analysis aimed to synthetize the evidence on the association between neighbourhood crime and individual-level mental health problems.

METHOD

We searched 11 electronic databases, grey literature and reference lists to identify relevant studies published before September 14, 2020. Studies were included if they reported confounder-adjusted associations between objective or perceived area-level crime and anxiety, depression, psychosis or psychological distress/internalising symptoms in non-clinical samples. Effect measures were first converted into Fisher's z-s, pooled with three-level random-effects meta-analyses, and then transformed into Pearson's correlation coefficients. Univariate and multivariate mixed-effects models were used to explore between-study heterogeneity.

RESULTS

We identified 63 studies reporting associations between neighbourhood crime and residents' mental health. Pooled associations were significant for depression (r = 0.04, 95% CI 0.03-0.06), psychological distress (r = 0.04, 95% CI 0.02-0.06), anxiety (r = 0.05, 95% CI 0.01-0.10), and psychosis (r = 0.04, 95% CI 0.01-0.07). Moderator analysis for depression and psychological distress identified stronger associations with perceived crime measurement and weaker in studies adjusted for area-level deprivation. Importantly, even after accounting for study characteristics, neighbourhood crime remained significantly linked to depression and psychological distress. Findings on anxiety and psychosis were limited due to low number of included studies.

CONCLUSIONS

Neighbourhood crime is an important contextual predictor of mental health with implications for prevention and policy. Area-based crime interventions targeting the determinants of crime, prevention and service allocation to high crime neighbourhoods may have public mental health benefits. Future research should investigate the causal pathways between crime exposure and mental health, identify vulnerably groups and explore policy opportunities for buffering against the detrimental effect of neighbourhood stressors.

Neighborhood Predictors of Outpatient Mental Health Visits Among Persons With Comorbid Medical and Serious Mental Illnesses

OBJECTIVE

Individuals with serious mental illnesses are at risk of receiving inadequate outpatient mental health services, increasing the likelihood of medication nonadherence, readmission, and self-harm. The purpose of this study was to identify individual- and neighborhood-level factors associated with outpatient mental health visits.

METHODS

This study included 418 participants from two randomized trials of patients with comorbid medical conditions and serious mental illnesses across two study sites between 2011 and 2017. On the basis of individual addresses, data were collected about participants' distance to the nearest mental health facility and 13 neighborhood characteristics from the American Community Survey. Three neighborhood-level factors were derived from factor analysis. Poisson regression was used to assess associations between individual- and neighborhood-level characteristics and the number of visits to mental health providers. Known individual-level risk factors for outpatient follow-up were mutually adjusted in a model with neighborhood covariates added.

RESULTS

Male gender, older age, unemployment, and lower education level were associated with less outpatient mental health service utilization. Neighborhood-level residential mobility, defined as the combination of percentage of residents living in a different house in the past year and percentage of non-owner-occupied housing, was significantly associated with fewer mental health service visits even after controlling for other neighborhood- and individual-level factors.

CONCLUSIONS

Among individuals with comorbid medical conditions and serious mental illnesses, living in neighborhoods with higher residential mobility was associated with fewer visits to outpatient mental health providers. This finding suggests the importance of recognizing social conditions that may shape clinical interactions.

Urbanicity: The need for new avenues to explore the link between urban living and psychosis

AIM

A growing body of evidence suggests that urban living contributes to the development of psychosis. However, the mechanisms underlying this phenomenon remain unclear. This paper aims to explore the best available knowledge on the matter, identify research gaps and outline future prospects for research strategies.

METHOD

A comprehensive literature survey on the main computerized medical research databases, with a time limit up to August 2017 on the issue of urbanicity and psychosis has been conducted.

RESULTS

The impact of urbanicity may result from a wide range of factors (from urban material features to stressful impact of social life) leading to "urban stress." The latter may link urban upbringing to the development of psychosis through overlapping neuro- and socio-developmental pathways, possibly unified by dopaminergic hyperactivity in mesocorticolimbic system. However, "urban stress" is poorly defined and research based on patients' experience of the urban environment is scarce.

CONCLUSIONS

Despite accumulated data, the majority of studies conducted so far failed to explain how specific factors of urban environment combine in patients' daily life to create protective or disruptive milieus. This undermines the translation of a vast epidemiological knowledge into effective therapeutic and urbanistic developments. New studies on urbanicity should therefore be more interdisciplinary, bridging knowledge from different disciplines (psychiatry, epidemiology, human geography, urbanism, etc.) in order to enrich research methods, ensure the development of effective treatment and preventive strategies as well as create urban environments that will contribute to mental well-being.

Perceived neighborhood social cohesion and cardiometabolic risk: a gene × environment study

People living in socially cohesive neighborhoods generally have better health. We extend this research by evaluating the hypothesis that perceived neighborhood cohesion may influence health by attenuating genetic liability for cardiometabolic risk factors. Using data from the Health and Retirement Study (n = 6615; mean age 69.7), we conducted a gene × environment interaction study hypothesizing that perceived neighborhood cohesion would attenuate the link between polygenic scores for waist-to-hip ratio (WHR) and body mass index and a measure of multisystem cardiometabolic risk (systolic and diastolic blood pressure, heart rate, A1c, C-reactive protein, and total and high-density lipoprotein cholesterol). In support of the hypothesis, results indicated that among people perceiving low neighborhood cohesion, higher WHR polygenic scores were associated with greater cardiometabolic risk. In contrast, the genetic-cardiometabolic risk link was much attenuated among those living in neighborhoods perceived as socially cohesive. Our results support community-level interventions to enhance the social cohesiveness of individuals' neighborhoods which may provide health benefits by reducing the risks associated with known genetic risk factors.

Neighborhood crime, socioeconomic status, and suspiciousness in adolescents and young adults at Clinical High Risk (CHR) for psychosis

INTRODUCTION

Contextual factors representing chronic stressors, such as neighborhood crime characteristics, have been repeatedly linked to compromised mental and physical health, and may contribute to the pathologizing of normative/non-clinical experiences. However, the impact of such structural factors has seldom been incorporated in Clinical High Risk (CHR) for psychosis research. Understanding how context can influence the presence or severity of symptoms such as suspiciousness/paranoia may have important relevance for promoting valid and reliable assessment, as well as for understanding ways in which environment may be related to illness development and expression.

METHODS

A total of 126 adolescents and young adults (nCHR = 63, ncontrol = 63) underwent clinical interviews for Clinical High-Risk syndromes. Neighborhood crime indices and socioeconomic status were calculated through geocoding and extracting of publicly available Census and Federal Bureau of Investigation (FBI) data. Analyses examined presence of associations between neighborhood crime indices, socioeconomic status, suspiciousness and total symptoms.

RESULTS

Greater neighborhood crime was related to increased suspiciousness in CHR individuals, even after controlling for neighborhood socioeconomic status, r = 0.27, p = .03. Neighborhood crime was not related to total symptoms, and neither was neighborhood socioeconomic status.

DISCUSSION

Results suggest neighborhood crime uniquely related to suspiciousness symptoms in CHR individuals, while this was not the case for healthy volunteers (HV). Future work will be critical for determining the extent to which assessors are pathologizing experiences that are normative for a particular context, or rather, if a stressful context is serving as a sufficient environmental stressor to unmask emerging psychosis.

Are familial liability for schizophrenia and obstetric complications independently associated with risk of psychotic illness, after adjusting for other environmental stressors in childhood?

OBJECTIVE

The interplay between genetic and environmental factors on risk for psychotic illness remains poorly understood. The aim of this study was to estimate independent and combined effects of familial liability for schizophrenia and exposure to obstetric complications on risk for developing psychotic illness, covarying with exposure to other environmental stressors.

METHODS

This whole-population birth cohort study used record linkage across Western Australian statewide data collections (midwives, psychiatric, hospital admissions, child protection, mortality) to identify liveborn offspring (n = 1046) born 1980-1995 to mothers with schizophrenia, comparing them to offspring of mothers with no recorded psychiatric history (n = 298,370).

RESULTS

Both maternal schizophrenia and pregnancy complications were each significantly associated with psychotic illness in offspring, with no interaction. Non-obstetric environmental stressors significantly associated with psychotic illness in offspring included the following: being Indigenous; having a mother who was not in a partnered relationship; episodes of disrupted parenting due to hospitalisation of mother, father or child; abuse in childhood; and living in areas of greatest socioeconomic disadvantage and with elevated rates of violent crime. Adjustment for these other environmental stressors reduced the hazard ratio for maternal schizophrenia substantially (from hazard ratio: 5.7, confidence interval: 4.5-7.2 to hazard ratio: 3.5, confidence interval: 2.8-4.4), but not the estimate for pregnancy complications (hazard ratio: 1.1, confidence interval: 1.0-1.2). The population attributable fraction for maternal schizophrenia was 1.4 and for pregnancy complications was 2.1.

CONCLUSION

Our finding of a substantial decrease in risk of psychotic illness associated with familial liability for psychosis following adjustment for other environmental stressors highlights potentially modifiable risk factors on the trajectory to psychotic illness and suggests that interventions that reduce or manage exposure to these risks may be protective, despite a genetic liability.

Development of the Australian neighborhood social fragmentation index and its association with spatial variation in depression across communities

PURPOSE

We know little about how community structures influence the risk of common mental illnesses. This study presents a new way to establish links between depression and social fragmentation, thereby identifying pathways to better target mental health services and prevention programs to the right people in the right place.

METHOD

A principal components analysis (PCA) was conducted to develop the proposed Australian neighborhood social fragmentation index (ANSFI). General practice clinical data were used to identify cases of diagnosed depression. The association between ANSFI and depression was explored using multilevel logistic regression. Spatial hot spots (clusters) of depression prevalence and social fragmentation at the statistical area level 1 (SA1) were examined.

RESULTS

Two components of social fragmentation emerged, reflecting fragmentation related to family structure and mobility. Individuals treated for depression in primary care were more likely to live in neighborhoods with lower socioeconomic status and with higher social fragmentation related to family structure. A 1-SD increase in social fragmentation was associated with a 16% higher depression prevalence (95% CI 11%, 20%). However, the association attenuated with adjustment for neighborhood socio-economic status. Considerable spatial variation in social fragmentation and depression patterns across communities was observed.

CONCLUSIONS

Developing a social fragmentation index for the first time in Australia at a small area level generates a new line of knowledge on the impact of community structures on health risks. Findings may extend our understanding of the mechanisms that drive geographical variation in the incidence of common mental disorders and mental health care.

Cultural differences in positive psychotic experiences assessed with the Community Assessment of Psychic Experiences-42 (CAPE-42): a comparison of student populations in the Netherlands, Nigeria and Norway

BACKGROUND

Previous studies have suggested that culture impacts the experience of psychosis. The current study set out to extend these findings by examining cultural variation in subclinical positive psychotic experiences in students from The Netherlands, Nigeria, and Norway. Positive psychotic experiences were hypothesized to (i) be more frequently endorsed by, and (ii) cause less distress in Nigerian vs. Dutch and Norwegian students.

METHODS

Psychology students, aged 18 to 30 years, from universities in the Netherlands (n = 245), Nigeria (n = 478), and Norway (n = 162) were assessed cross-sectionally with regard to the frequency of subclinical positive psychotic experiences and related distress, using the Community Assessment of Psychic Experiences (CAPE-42). Multi-group confirmatory factor analysis and multivariate analysis of covariance were performed to assess measurement invariance of the positive symptom dimension (CAPE-Pos) and compare mean frequency and associated distress of positive psychotic experiences across study samples.

RESULTS

Only CAPE-Pos items pertaining to the dimensions 'strange experiences' and 'paranoia' met assumptions for (partial) measurement invariance. Frequencies of these experiences were higher in the Nigerian sample, compared to both the Dutch and Norwegian samples, which were similar. In addition, levels of experience-related distress were similar or higher in the Nigerian sample compared to respectively the Dutch and Norwegian samples.

CONCLUSION

Although positive psychotic experiences may be more commonly endorsed in non-Western societies, our findings do not support the notion that they represent a more benign, and hence less distressing aspect of human experience. Rather, the experience of psychotic phenomena may be just as, if not more, distressing in African than in European culture. However, observed differences in CAPE-Pos frequency and distress between samples from different cultural settings may partly reflect differences in the measure rather than in the latent trait. Future studies may therefore consider further cross-cultural adaptation of CAPE-42, in addition to explicitly examining cultural acceptance of psychotic phenomena, and environmental and other known risk factors for psychosis, when comparing and interpreting subclinical psychotic phenomena across cultural groups.

Incidence of treated first episode psychosis from an Australian early intervention service and its association with neighbourhood characteristics

OBJECTIVES

Psychotic disorder incidence varies geographically and is associated with neighbourhood characteristics, including social deprivation, population density, unemployment, social capital or social fragmentation. Yet it is not known whether these findings are applicable to Australia's unique geography. This study aimed to determine whether the incidence of first episode psychosis (FEP) varies according to neighbourhood characteristics in an Australian cohort.

METHOD

This study included all young people, aged 15 to 24, with an FEP who attended Orygen Youth Health in Melbourne, from a geographically defined catchment area encompassing Northern and Western Melbourne, over a 44-month period. Neighbourhood demographic data was collected from the 2011 Australian National Census. Negative binomial regression was used to determine incidence rate ratios controlled for age, sex and migrant status.

RESULTS

A total of 747 young people had an FEP during the 44-month study period and 722 were included in this study. Of these, 58.0% were males and 67.9% had a non-affective psychotic disorder; the mean age of the cohort was 19.1 years. The incidence of FEP in young people aged 15 to 24 in the catchment area was 123.2 per 100,000 person-years. There was a higher incidence of FEP in neighbourhoods of greatest social deprivation (IRR = 1.65, CI = 1.06-2.51, p = .02), highest unemployment (IRR = 1.56, CI = 1.04-2.35, p = .03) and above average social fragmentation (IRR = 1.42, CI = 1.02-1.97, p = .04), when controlled for age, sex and migrant status.

CONCLUSIONS

This study highlights variation in psychotic disorder incidence and the need for this disparity to be reflected in appropriate resource allocation.

Ethnic minority position and migrant status as risk factors for psychotic symptoms in the general population: a meta-analysis

Psychotic symptoms (PS) are experienced by a substantial proportion of the general population. When not reaching a threshold of clinical relevance, these symptoms are defined as psychotic experiences (PEs) and may exist on a continuum with psychotic disorders. Unfavorable socio-environmental conditions, such as ethnic minority position (EMP) and migrant status (MS), may increase the risk of developing PS and PEs. We conducted an electronic systematic review and a meta-analysis assessing the role of EMP and MS for the development and persistence of PS in the general population. Sub-group analyses were performed investigating the influence of ethnic groups, host countries, age, types of PS, and scales. Twenty-four studies met our inclusion criteria. EMP was a relevant risk factor for reporting PS [odds ratio (OR) 1.44, 95% confidence interval (CI) 1.22-1.70) and PEs (OR 1.36, 95% CI 1.16-1.60). The greatest risk was observed in people from the Maghreb and the Middle East ethnic groups in Europe (OR 3.30, 95% CI 2.09-5.21), in Hispanic in the USA (OR 1.98, 95% CI 1.43-2.73), and in the Black populations (OR 1.85, 95% CI 1.39-2.47). We found a significant association between MS and delusional symptoms (OR 1.47, 95% CI 1.33-1.62). We found no association between EMP and persistence of PEs.EMP was associated with increased risk of reporting PS and PEs, and the risk was higher in ethnic groups facing deprivation and discrimination. We found an association between MS and delusional symptoms. These results raise questions about the precise role of socio-environmental factors along the psychosis continuum.

A systematic review and meta-analysis of the incidence of psychotic disorders: the distribution of rates and the influence of gender, urbanicity, immigration and socio-economic level

BACKGROUND

Considering existing knowledge on the relationship between certain environmental factors and incidence rates of psychosis, we carried out a systematic review to provide a broad and updated picture of the incidences of different psychotic disorder subgroups worldwide and how some environmental factors influence these rates.

METHODS

Studies with original data related to the incidence of psychosis (published between 2000 and 2015) were identified via searching electronic databases (CINAHL, MEDLINE, PSYCINFO, PUBMED, and SCOPUS). Data on the following risk factors were extracted: gender, urbanicity, immigration and socio-economic level. Descriptive appraisals of variation in incidence rates (IR) and incidence rate ratios (IRR), with a 95% confidence interval were calculated. In addition, a meta-analysis was performed to calculate IR pooled by diagnosis group and IRR pooled by diagnosis and gender, urbanity, immigration and socio-economic level, using a random effects model.

RESULTS

We identified 33 reports to analyse. Overall IR per 100 000 persons for non-affective psychoses (IR pooled = 22.53 (16.51-28.54)) were higher than affective psychoses (IR pooled = 7.12 (5.03-9.22)). There was an increase in rates of psychosis in men v. women (IRR pooled = 1.54 (1.37-1.72)), in urban v. rural areas (IRR pooled = 1.64 (1.38-1.95)), in immigrants v. natives (IRR pooled = 3.09 (2.74-3.49)), and in lower socio-economic level areas (IRR pooled = 1.78 (1.43-2.22)).

CONCLUSIONS

IR among different psychotic disorders was found to vary depending on gender, urbanicity, and immigration (as most of the previous literature focuses on non-affective psychosis or schizophrenia).

Perceived neighborhood social cohesion and cardiometabolic risk: a gene × environment study

People living in socially cohesive neighborhoods generally have better health. We extend this research by evaluating the hypothesis that perceived neighborhood cohesion may influence health by attenuating genetic liability for cardiometabolic risk factors. Using data from the Health and Retirement Study (n = 6,615; mean age 69.7), we conducted a gene × environment interaction study hypothesizing that perceived neighborhood cohesion would attenuate the link between polygenic scores for waist-to-hip ratio (WHR) and body mass index and a measure of multisystem cardiometabolic risk (systolic blood pressure [SBP] and diastolic blood pressure [DBP], heart rate, A1c, C-reactive protein, and total and high-density lipoprotein cholesterol). In support of the hypothesis, results indicated that among people perceiving low neighborhood cohesion, higher WHR polygenic scores were associated with greater cardiometabolic risk. In contrast, the genetic-cardiometabolic risk link was much attenuated among those living in neighborhoods perceived as socially cohesive. Our results support community-level interventions to enhance the social cohesiveness of individuals' neighborhoods which may provide health benefits by reducing the risks associated with known genetic risk factors.

Cumulative Effects of Neighborhood Social Adversity and Personal Crime Victimization on Adolescent Psychotic Experiences

BACKGROUND

Little is known about the impact of urbanicity, adverse neighborhood conditions and violent crime victimization on the emergence of adolescent psychotic experiences.

METHODS

Participants were from the Environmental Risk (E-Risk) Longitudinal Twin Study, a nationally-representative cohort of 2232 British twins who were interviewed about adolescent psychotic experiences at age 18. Urbanicity, neighborhood characteristics, and personal victimization by violent crime were measured during childhood and adolescence via geocoded census data, surveys of over 5000 immediate neighbors of the E-Risk participants, and interviews with participants themselves.

RESULTS

Adolescents raised in urban vs rural neighborhoods were significantly more likely to have psychotic experiences (OR = 1.67, 95% CI = 1.21-2.30, P = .002). This association remained significant after considering potential confounders including family socioeconomic status, family psychiatric history, and adolescent substance problems (OR = 1.43, 95% CI = 1.01-2.03, P = .042), but became nonsignificant after considering adverse social conditions in urban neighborhoods such as low social cohesion and high neighborhood disorder (OR = 1.35, 95% CI = 0.94-1.92, P = .102). The combined association of adverse neighborhood social conditions and personal crime victimization with adolescent psychotic experiences (adjusted OR = 4.86, 95% CI = 3.28-7.20, P < .001) was substantially greater than for either exposure alone, highlighting a potential interaction between neighborhood conditions and crime victimization (interaction contrast ratio = 1.81, 95% CI = -0.03 to 3.65) that was significant at the P = .054 level.

CONCLUSIONS

Cumulative effects of adverse neighborhood social conditions and personal victimization by violent crime during upbringing partly explain why adolescents in urban settings are more likely to report psychotic experiences. Early intervention efforts for psychosis could be targeted towards victimized youth living in urban and socially adverse neighborhoods.

Mechanisms underlying metabolic disturbances associated with psychosis and antipsychotic drug treatment

The increase in cardiovascular disease and reduced life expectancy in schizophrenia likely relate to an increased prevalence of metabolic disturbances. Such metabolic risk factors in schizophrenia may result from both symptom-related effects and aetiological factors. However, a major contributory factor is that of treatment with antipsychotic drugs. These drugs differ in effects on body weight; the underlying mechanisms are not fully understood and may vary between drugs, but may include actions at receptors associated with the hypothalamic control of food intake. Evidence supports 5-hydroxytryptamine receptor 2C and dopamine D2 receptor antagonism as well as antagonism at histamine H1 and muscarinic M3 receptors. These M3 receptors may also mediate the effects of some drugs on glucose regulation. Several antipsychotics showing little propensity for weight gain, such as aripiprazole, have protective pharmacological mechanisms, rather than just the absence of a hyperphagic effect. In addition to drug differences, there is large individual variation in antipsychotic drug-induced weight gain. This pharmacogenetic association reflects genetic variation in several drug targets, including the 5-hydroxytryptamine receptor 2C, as well as genes involved in obesity and metabolic disturbances. Thus predictive genetic testing for drug-induced weight gain would represents a first step towards personalised medicine addressing this severe and problematic iatrogenic disease.

Ethnic inequalities in psychological distress among urban residents in the Netherlands: A moderating role of neighborhood ethnic diversity?

The main purpose of this study was to investigate whether neighborhood ethnic diversity moderated the association between ethnicity and psychological distress in the four largest cities of Netherlands. Multilevel linear regression analysis was used to assess whether the association between ethnicity and psychological distress differed by levels of neighborhood ethnic diversity. Results showed that the Turkish and Moroccan residents reported significantly higher psychological distress than native Dutch and Surinamese residents. In high ethnic diverse neighborhoods Turkish residents reported significantly less psychological distress than in low ethnic diverse neighborhoods. Ethnic diversity amplifies the risk of depression for some but not all ethnic minorities.

Genetic variation in the 3'-untranslated region of PAK1 influences schizophrenia susceptibility

The present study aimed to investigate the association of two polymorphisms (rs2844337 and rs11237200) in the P21 protein (cell division control protein 42/Rac)-activated kinase 1 gene with susceptibility to schizophrenia (SCZ) in Chinese Zhuang and Chinese Han populations. A total of 700 patients with SCZ and 700 healthy controls were recruited. Rs2844337 and rs11237200 polymorphisms were genotyped using Sequenom technology. A total of 591 patients completed the Positive and Negative Syndrome Scale (PANSS) assessment. Data were statistically analyzed using PLINK version 1.07 and SPSS version 17.0. In the Chinese Han population, the genotypic (P=0.038) and allelic (P=0.033) frequencies of the 3'-untranslated region (UTR) genetic variation of rs2844337 in patients were significantly decreased compared to that in controls; these frequencies were significantly associated with SCZ susceptibility in the additive model (P_adj=0.032) and in the recessive model (P_adj=0.031). Moreover, the TG haplotype constructed by rs2844337 and rs11237200 polymorphisms remained significantly associated with SCZ risk following adjustment for gender and age and applying a Bonferroni correction in the Chinese Han population (P_adj=0.003, P_BC=0.009). The adjacent 5'-UTR genetic variation of rs11237200 was significantly associated with the total score (P_adj=0.006), positive scale score (P_adj=0.014) and general psychopathology scale scores (P_adj=0.009) in the recessive model of the Chinese Han population. However, these polymorphisms were not significantly associated with SCZ susceptibility or the PANSS scores in the Chinese Zhuang population. In conclusion, variations in the PAK1 gene influenced the susceptibility and severity of the clinical symptoms of SCZ in the Chinese Han population investigated in the present study.

The rs11191580 variant of the NT5C2 gene is associated with schizophrenia and symptom severity in a South Chinese Han population: evidence from GWAS

Objective:

Recent genome-wide association studies have identified a significant relationship between the NT5C2 variant rs11191580 and schizophrenia (SCZ) in European populations. This study aimed to validate the association of rs11191580 polymorphism with SCZ risk in a South Chinese Han population. The relationship of this polymorphism with the severity of SCZ clinical symptoms was also explored.

Methods:

A case-control study was performed in 462 patients with SCZ and 598 healthy controls. rs11191580 was genotyped by the Sequenom MassARRAY iPLEX platform. A total of 459 SCZ patients completed the Positive and Negative Syndrome Scale (PANSS) evaluation. Data were analyzed by PLINK software.

Results:

We confirmed an association of the rs11191580 polymorphism with SCZ risk in South Chinese Han under a dominant genetic model (OR_adj = 0.769; 95%CI_adj = 0.600-0.984; p_adj = 0.037). PANSS scores showed a significant association between variant rs11191580 and total score (p_adj = 0.032), lack of response scale score (p_adj = 0.022), and negative scale score (additive: p_adj = 0.004; dominant: p_adj = 0.016; recessive: p_adj = 0.021) after data were adjusted for age and sex.

Conclusion:

NT5C2 variant rs11191580 conferred susceptibility to SCZ and affected the clinical symptoms of SCZ in a South Chinese Han population.

Why Are Children in Urban Neighborhoods at Increased Risk for Psychotic Symptoms? Findings From a UK Longitudinal Cohort Study

BACKGROUND

Urban upbringing is associated with a 2-fold adulthood psychosis risk, and this association replicates for childhood psychotic symptoms. No study has investigated whether specific features of urban neighborhoods increase children's risk for psychotic symptoms, despite these early psychotic phenomena elevating risk for schizophrenia and other psychiatric disorders in adulthood.

METHODS

Analyses were conducted on over 2000 children from the Environmental Risk (E-Risk) Longitudinal Twin Study, a nationally-representative cohort of UK-born twins. Neighborhood-level characteristics were assessed for each family via: a geodemographic discriminator indexing neighborhood-level deprivation, postal surveys of over 5000 residents living alongside the children, and in-home interviews with the children's mothers. Children were interviewed about psychotic symptoms at age 12. Analyses were adjusted for important family-level confounders including socioeconomic status (SES), psychiatric history, and maternal psychosis.

RESULTS

Urban residency at age-5 (OR = 1.80, 95% CI = 1.16-2.77) and age-12 (OR = 1.76, 95% CI = 1.15-2.69) were both significantly associated with childhood psychotic symptoms, but not with age-12 anxiety, depression, or antisocial behavior. The association was not attributable to family SES, family psychiatric history, or maternal psychosis, each implicated in childhood mental health. Low social cohesion, together with crime victimization in the neighborhood explained nearly a quarter of the association between urbanicity and childhood psychotic symptoms after considering family-level confounders.

CONCLUSIONS

Low social cohesion and crime victimization in the neighborhood partly explain why children in cities have an elevated risk of developing psychotic symptoms. Greater understanding of the mechanisms leading from neighborhood-level exposures to psychotic symptoms could help target interventions for emerging childhood psychotic symptoms.

Neighbourhood level social deprivation and the risk of psychotic disorders: a systematic review

PURPOSE

The incidence of psychotic disorders varies according to the geographical area, and it has been investigated whether neighbourhood level factors may be associated with this variation. The aim of this systematic review is to collate and appraise the literature on the association between social deprivation and the incidence or risk for psychotic disorders.

METHOD

A systematic review was conducted, and studies were included if they were in English, provided a measure of social deprivation for more than one geographically defined area and examined either the correlation, rate ratio or risk of psychotic disorder. A defined search strategy was undertaken with Medline, CINAHL Plus and PsychInfo databases.

RESULTS

A total of 409 studies were identified in the search, of which 28 fulfilled the inclusion criteria. Of these, four examined the association between social deprivation at the time of birth, three examined the putative prodrome of psychosis or those at ultra-high risk (UHR) for psychosis, and 23 examined the time at presentation with a first episode of psychosis (FEP) (one study examined two time points and one study included both UHR and FEP). Three of the studies that examined the level of social deprivation at birth found an association with a higher risk for psychotic disorders and increased social deprivation. Seventeen of the 23 studies found that there was a higher risk or rate of psychotic disorders in more deprived neighbourhoods at the time of presentation; however, adjusting for individual factors tended to weaken this association. Limited research has been conducted in the putative prodromal stage and has resulted in conflicting findings.

CONCLUSIONS

Research conducted to date has not definitively identified whether the association is a result of social causation or social drift; however, the findings do have significant implications for service provision, such as the location and access of services.

Context matters: The impact of neighborhood crime and paranoid symptoms on psychosis risk assessment

Psychosis risk assessment measures probe for paranoid thinking, persecutory ideas of reference, and suspiciousness as part of a psychosis risk construct. However, in some cases, these symptoms may reflect a normative, realistic, and even adaptive response to environmental stressors rather than psychopathology. Neighborhood characteristics, dangerousness for instance, are linked to levels of fear and suspiciousness that can be theoretically unrelated to psychosis. Despite this potential confound, psychosis-risk assessments do not explicitly evaluate neighborhood factors that might (adaptively) increase suspiciousness. In such cases, interviewers run the risk of misinterpreting adaptive suspiciousness as a psychosis-risk symptom. Ultimately, the degree to which neighborhood factors contribute to psychosis-risk assessment remains unclear. The current study examined the relation between neighborhood crime and suspiciousness as measured by the SIPS among predominantly African American help-seeking adolescents (N=57) living in various neighborhoods in Baltimore City. Uniform Crime Reports, including violent and property crime for Baltimore City, were used to calculate a proxy of neighborhood crime. This crime index correlated with SIPS suspiciousness (r(55)=.32, p=.02). Multiple regression analyses demonstrated that increased neighborhood crime significantly predicted suspiciousness over and above the influence of the other SIPS positive symptoms in predicting suspiciousness. Findings suggest that neighborhood crime may in some cases account for suspiciousness ascertained as part of a psychosis risk assessment, and therefore sensitivity to contextual factors is important when evaluating risk for psychosis.

An integrated network model of psychotic symptoms

The full body of research on the nature of psychosis and its determinants indicates that a considerable number of factors are relevant to the development of hallucinations, delusions, and other positive symptoms, ranging from neurodevelopmental parameters and altered connectivity of brain regions to impaired cognitive functioning and social factors. We aimed to integrate these factors in a single mathematical model based on network theory. At the microscopic level this model explains positive symptoms of psychosis in terms of experiential equivalents of robust, high-frequency attractor states of neural networks. At the mesoscopic level it explains them in relation to global brain states, and at the macroscopic level in relation to social-network structures and dynamics. Due to the scale-free nature of biological networks, all three levels are governed by the same general laws, thereby allowing for an integrated model of biological, psychological, and social phenomena involved in the mediation of positive symptoms of psychosis. This integrated network model of psychotic symptoms (INMOPS) is described together with various possibilities for application in clinical practice.