Association of Environment With the Risk of Developing Psychotic Disorders in Rural Populations: Findings from the Social Epidemiology of Psychoses in East Anglia Study

Urbanicity and psychotic disorders: Facts and hypotheses

In the present qualitative literature review, we summarise data on psychotic disorders and urbanicity, focusing particularly on recent findings. Longitudinal studies of the impact of urbanicity on the risk for psychotic disorders have consistently shown a significant association, with a relative risk between 2 and 2.5. However, most of the original studies were conducted in Western Europe, and no incidence studies were conducted in low- and middle-income countries. European studies suggest that neighbourhood-level social fragmentation and social capital may partly explain this association. Exposure to air pollution (positive association) and green space (negative association) may also be part of the explanation, but to date, available data do not make it possible to conclude if they act independently from urbanicity, or as part of the effect of urbanicity on psychotic disorders. Finally, several studies have consistently shown significant associations between the polygenic risk score for schizophrenia and urbanicity, with several possible explanations (pleiotropic effects, results of prodromic symptoms, or selection/intergenerational hypothesis). Thus, more studies are needed to understand the factors that explain the association between urbanicity and the risk of psychotic disorders. Further studies should account for the interdependence and/or interactions of different psychosocial and physical exposures (as well as gene-environment interactions), and explore this association in low- and middle-income countries.

Associations Between Childhood Area-Level Social Fragmentation, Maladaptation to School, and Social Functioning Among Healthy Youth and Those at Clinical High Risk for Psychosis

BACKGROUND AND HYPOTHESIS

Although studies have identified social fragmentation as an important risk factor for schizophrenia and other psychotic disorders, it is unknown whether it may impact social functioning. This study investigates whether social fragmentation during childhood predicts maladaptation to school as well as social functioning during childhood and adulthood.

STUDY DESIGN

Data were collected from the North American Prodrome Longitudinal Study. Participants included adults at clinical high risk for psychosis (CHR-P) and healthy comparisons (HC). Maladaptation to school and social functioning during childhood were assessed retrospectively and social functioning in adulthood was assessed at baseline.

STUDY RESULTS

Greater social fragmentation during childhood was associated with greater maladaptation to school (adjusted β = 0.21; 95% CI: 0.02 to 0.40). Social fragmentation was not associated with social functioning during childhood (unadjusted β = -0.08; 95% CI: -0.31 to 0.15). However, greater social fragmentation during childhood predicted poorer social functioning in adulthood (adjusted β = -0.43; 95% CI: -0.79 to -0.07). Maladaptation to school mediated 15.7% of the association between social fragmentation and social functioning. The association between social fragmentation and social functioning was stronger among adults at CHR-P compared to HC (adjusted β = -0.42; 95% CI: -0.82 to -0.02).

CONCLUSIONS

This study finds that social fragmentation during childhood is associated with greater maladaptation to school during childhood, which in turn predicts poorer social functioning in adulthood. Further research is needed to disentangle aspects of social fragmentation that may contribute to social deficits, which would have implications for the development of effective interventions at the individual and community levels.

Investigating social deprivation and comorbid mental health diagnosis as predictors of treatment access among patients with an opioid use disorder using substance use services: a prospective cohort study

BACKGROUND

Opioid use is a major public health concern across the globe. Opioid use and subsequent access to care is often shaped by co-occurring issues faced by people using opioids, such as deprivation, mental ill-health, and other forms of substance use. We investigated the role of social deprivation and comorbid mental health diagnoses in predicting re-engagement with substance use services or contact with crisis and inpatient services for individuals with opioid use disorder in secondary mental health care in inner-city London.

METHODS

We conducted a prospective cohort study which followed individuals diagnosed with a first episode of opioid use disorder who accessed substance use services between September 2015 and May 2020 for up to 12 months, using anonymised electronic health records. We employed negative binominal regression and Cox proportional survival analyses to assess associations between exposures and outcomes.

RESULTS

Comorbid mental health diagnoses were associated with higher contact rates with crisis/inpatient services among people with opioid use disorder: incidence rate ratios (IRR) and 95% confidence intervals (CI) were 3.91 (1.74-9.14) for non-opioid substance use comorbidity, 8.92 (1.81-64.4) for a single comorbid mental health diagnosis, and 15.9 (5.89-47.5) for multiple comorbid mental health diagnoses. Social deprivation was not associated with contact rates with crisis/inpatient services within this sample. Similar patterns were found with time to first crisis/inpatient contact. Social deprivation and comorbid mental health diagnoses were not associated with re-engagement with substance use services.

CONCLUSION

Comorbid substance and mental health difficulties amongst people with an opioid use disorder led to earlier and more frequent contact with crisis/inpatient mental health services during the first 12 months of follow up. Given the common co-occurrence of mental health and substance use disorders among those who use opioids, a better understanding of their wider needs (such as social, financial and other non-medical concerns) will ensure they are supported in their treatment journeys.

The ethnic density effect as a contextual influence in ecological disease models: Establishing its quantitative expression

Research suggests higher neighbourhood ethnic minority density to be associated with lessened chances of ethnic group illness. We focus on the density effect on psychosis, arguing that (at higher ethnic concentrations) it acts as a contextual influence attenuating the compositional influence whereby minority ethnicity is associated with higher psychosis risk. In terms of ecological disease regression, the ethnic density effect will then be apparent in nonlinear impacts of minority concentration. Contextual effects may also be evident in spatially varying regression coefficient models for psychosis. Nonlinearity or heterogeneity may be associated with other contextual processes where geography modifies demography (e.g. deprivation amplification). We illustrate these issues with an analysis of psychosis prevalence in 4835 London neighbourhoods. The data are collected in primary care (during 2019/20) using clinical diagnosis (e.g. based on referrals to specialists or psychosis hospitalisation), and refer to patients currently under care: such care may extend retrospectively over several years. The data offer a complete population perspective in contrast to survey data, which typically offer limited geographic perspectives. We consider impacts on psychosis prevalence of non-white ethnicity, as well as those of deprivation, social fragmentation and urbanicity. We find evidence suggesting nonlinear impacts of non-white ethnicity on psychosis (essentially flat risk above a threshold concentration), but find no evidence for deprivation amplification.

The incidence of psychotic disorders in the Republic of Ireland: a systematic review

OBJECTIVES

Despite a substantial epidemiological literature on the incidence of psychotic disorders in Ireland, no systematic review has previously been undertaken. Such evidence can help inform understanding of need for psychosis care.

METHODS

We conducted a prospectively registered systematic review (PROSPERO: CRD42021245891) following PRISMA guidelines. We searched four databases (Medline, PsycInfo, Web of Science, Embase) for papers containing incidence data on non-organic psychotic disorders, in people 16-64 years, published between 1950 and 2021 in the general adult population. We conducted duplicate screening, risk of bias assessments, and extracted data to a standardised template. We undertook a narrative synthesis for each major diagnostic outcome. Random effects meta-analyses were conducted for comparisons with ≥5 incidence rates.

RESULTS

Our search yielded 1975 non-duplicate citations, of which 23 met inclusion criteria, containing incidence data ascertained between 1974 and 2016 (median study quality: 5/8; interquartile range: 4-6). Incidence of all psychotic disorders (N = 4 studies) varied from 22.0 (95%CI: 17.3-28.0) in Dublin to 34.1 per 100,000 person-years (95%CI: 31.0-37.5) in Cavan and Monaghan. The pooled incidence of schizophrenia (N = 6 studies, N = 8 settings) was 20.0 per 100,000 person-years, though with imprecision around this estimate (95%CI: 10.6-37.5; I2: 97.6%). Higher rates of most outcomes were observed in men. There was consistent evidence of raised rates in more deprived and fragmented social environments, but no clear pattern by rural-urban status.

CONCLUSIONS

Patterns of incidence of psychotic disorders in Ireland are broadly consistent with the wider literature from the Global North. Findings could help identify populations at higher risk of psychosis in Ireland.

A comparison of neighbourhood level variation and risk factors for affective versus non-affective psychosis

BACKGROUND

Studies typically highlight area level variation in the incidence of non-affective but not affective psychoses. We compared neighbourhood-level variation for both types of disorder, and the specific effects of neighbourhood urbanicity and ethnic density, using Danish national registry data.

METHODS

Population based cohort (2,224,464 people) followed from 1980 to 2013 with neighbourhood exposure measured at age 15 and incidence modelled using multilevel Poisson regression.

RESULTS

Neighbourhood variation was similar for both disorders with an adjusted median risk ratio of 1.37 (95% CI 1.34-1.39) for non-affective psychosis and 1.43 (1.38-1.49) for affective psychosis. Associations with neighbourhood urbanicity differed: living in the most compared to the least urban quintile at age 15 was associated with a minimal increase in subsequent affective psychosis, IRR 1.13 (1.01-1.27) but a substantial increase in rates of non-affective psychosis, IRR 1.66 (1.57-1.75). Mixed results were found for neighbourhood ethnic density: for Middle Eastern migrants there was an increased average incidence of both affective, IRR 1.54 (1.19-1.99), and non-affective psychoses, 1.13 (1.04-1.23) associated with each decrease in ethnic density quintile, with a similar pattern for African migrants, but for European migrants ethnic density appeared to be associated with non-affective psychosis only.

CONCLUSIONS

While overall variation and the effect of neighbourhood ethnic density were similar for both types of disorder, associations with urbanicity were largely confined to non-affective psychosis. This may reflect differences in aetiological pathways although the mechanism behind these differences remains unknown.

Area disadvantage and mental health over the life course: a 69-year prospective birth cohort study

PURPOSE

Existing evidence on the mental health consequences of disadvantaged areas uses cross-sectional or longitudinal studies with short observation periods. The objective of this research was to investigate this association over a 69-year period.

METHODS

Data were obtained from the MRC National Survey of Health and Development (NSHD; the British 1946 birth cohort), which consisted of 2125 participants at 69 years. We assessed longitudinal associations between area disadvantage and mental health symptoms at adolescence and adulthood with use of multilevel modelling framework.

RESULTS

After adjustment for father's social class, for each one percentage increase in area disadvantage at age 4, there was a 0.02 (95% CI 0.001, 0.04) mean increase in the total score of the neuroticism scale at age 13-15. After adjustment for father's social class, adult socio-economic position, cognitive ability and educational attainment, a one percentage increase in change score of area disadvantage between age 4 and 26 was associated with a mean increase in the total Psychiatric Symptom Frequency score (MD 0.06; 95% CI 0.007, 0.11). Similar associations were observed with change scores between ages 4, 53, 60 and total General Health Questionnaire-28 score at age 53 (MD 0.05; 95% CI 0.01, 0.11) and 60-64 (MD 0.06; 95% CI 0.009, 0.11).

CONCLUSIONS

Cohort members who experienced increasing area disadvantage from childhood were at increased risk of poor mental health over the life course. Population-wide interventions aiming at improving social and physical aspects of the early neighbourhood environment could reduce the socio-economic burden of poor mental health.

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.

Urbanicity and rates of untreated psychotic disorders in three diverse settings in the Global South

BACKGROUND

Extensive evidence indicates that rates of psychotic disorder are elevated in more urban compared with less urban areas, but this evidence largely originates from Northern Europe. It is unclear whether the same association holds globally. This study examined the association between urban residence and rates of psychotic disorder in catchment areas in India (Kancheepuram, Tamil Nadu), Nigeria (Ibadan, Oyo), and Northern Trinidad.

METHODS

Comprehensive case detection systems were developed based on extensive pilot work to identify individuals aged 18-64 with previously untreated psychotic disorders residing in each catchment area (May 2018-April/May/July 2020). Area of residence and basic demographic details were collected for eligible cases. We compared rates of psychotic disorder in the more v. less urban administrative areas within each catchment area, based on all cases detected, and repeated these analyses while restricting to recent onset cases (<2 years/<5 years).

RESULTS

We found evidence of higher overall rates of psychosis in more urban areas within the Trinidadian catchment area (IRR: 3.24, 95% CI 2.68-3.91), an inverse association in the Nigerian catchment area (IRR: 0.68, 95% CI 0.51-0.91) and no association in the Indian catchment area (IRR: 1.18, 95% CI 0.93-1.52). When restricting to recent onset cases, we found a modest positive association in the Indian catchment area.

CONCLUSIONS

This study suggests that urbanicity is associated with higher rates of psychotic disorder in some but not all contexts outside of Northern Europe. Future studies should test candidate mechanisms that may underlie the associations observed, such as exposure to violence.

The Critical Roles of Early Development, Stress, and Environment in the Course of Psychosis

Psychotic disorders are highly debilitating with poor prognoses and courses of chronic illness. In recent decades, conceptual models have shaped understanding, informed treatment, and guided research questions. However, these models have classically focused on the adolescent and early adulthood stages immediately preceding onset while conceptualizing early infancy through all of childhood as a unitary premorbid period. In addition, models have paid limited attention to differential effects of types of stress; contextual factors such as local, regional, and country-level characteristics or sociocultural contexts; and the timing of the stressor or environmental risk. This review discusses emerging research suggesting that (a) considering effects specific to neurodevelopmental stages prior to adolescence is highly informative, (b) understanding specific stressors and levels of environmental exposures (i.e., systemic or contextual features) is necessary, and (c) exploring the dynamic interplay between development, levels and types of stressors, and environments can shed new light, informing a specified neurodevelopmental and multifaceted diathesis-stress model.

The effects of social isolation stress and discrimination on mental health

Social isolation and discrimination are growing public health concerns associated with poor physical and mental health. They are risk factors for increased morbidity and mortality and reduced quality of life. Despite their detrimental effects on health, there is a lack of knowledge regarding translation across the domains of experimental research, clinical studies, and real-life applications. Here, we review and synthesize evidence from basic research in animals and humans to clinical translation and interventions. Animal models indicate that social separation stress, particularly in early life, activates the hypothalamic-pituitary-adrenal axis and interacts with monoaminergic, glutamatergic, and GABAergic neurotransmitter systems, inducing long-lasting reductions in serotonin turnover and alterations in dopamine receptor sensitivity. These findings are of particular importance for human social isolation stress, as effects of social isolation stress on the same neurotransmitter systems have been implicated in addictive, psychotic, and affective disorders. Children may be particularly vulnerable due to lasting effects of social isolation and discrimination stress on the developing brain. The effects of social isolation and loneliness are pronounced in the context of social exclusion due to discrimination and racism, during widespread infectious disease related containment strategies such as quarantine, and in older persons due to sociodemographic changes. This highlights the importance of new strategies for social inclusion and outreach, including gender, culture, and socially sensitive telemedicine and digital interventions for mental health care.

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.

The incidence of non-affective psychotic disorders in Chile between 2005 and 2018: results from a national register of over 30 000 cases

BACKGROUND

Evidence suggests the incidence of non-affective psychotic disorders (NAPDs) varies across persons and places, but data from the Global South is scarce. We aimed to estimate the treated incidence of NAPD in Chile, and variance by person, place and time.

METHODS

We used national register data from Chile including all people, 10-65 years, with the first episode of NAPD (International Classification of Diseases, Tenth Revision: F20-F29) between 1 January 2005 and 29 August 2018. Denominators were estimated from Chilean National Census data. Our main outcome was treated incidence of NAPD and age group, sex, calendar year and regional-level population density, multidimensional poverty and latitude were exposures of interest.

RESULTS

We identified 32 358 NAPD cases [12 136 (39.5%) women; median age-at-first-contact: 24 years (interquartile range 18-39 years)] during 171.1 million person-years [crude incidence: 18.9 per 100 000 person-years; 95% confidence interval (CI) 18.7-19.1]. Multilevel Poisson regression identified a strong age-sex interaction in incidence, with rates peaking in men (57.6 per 100 000 person-years; 95% CI 56.0-59.2) and women (29.5 per 100 000 person-years; 95% CI 28.4-30.7) between 15 and 19 years old. Rates also decreased (non-linearly) over time for women, but not men. We observed a non-linear association with multidimensional poverty and latitude, with the highest rates in the poorest regions and those immediately south of Santiago; no association with regional population density was observed.

CONCLUSION

Our findings inform the aetiology of NAPDs, replicating typical associations with age, sex and multidimensional poverty in a Global South context. The absence of association with population density suggests this risk may be context-dependent.

Equity in Mental Health Services for Youth at Clinical High Risk for Psychosis: Considering Marginalized Identities and Stressors

Prevention and early intervention programs have been initiated worldwide to serve youth at Clinical High Risk for Psychosis (CHR-P), who are adolescents and young adults experiencing subclinical psychosis and functional impairment. The primary goals of these efforts are to prevent or mitigate the onset of clinical psychosis, while also treating comorbid issues. It is important to consider issues of diversity, equity, and inclusion in CHR-P work, especially as these programs continue to proliferate around the world. Further, there is a long history in psychiatry of misdiagnosing and mistreating psychosis in individuals from racial and ethnic minority groups. Although there have been significant developments in early intervention psychosis work, there is evidence that marginalized groups are underserved by current CHR-P screening and intervention efforts. These issues are compounded by the contexts of continued social marginalization and significant mental health disparities in general child/adolescent services. Within this narrative review and call to action, we use an intersectional and minority stress lens to review and discuss current issues related to equity in CHR-P services, offer evidence-based recommendations, and propose next steps. In particular, our intersectional and minority stress lenses incorporate perspectives for a range of marginalized and underserved identities related to race, ethnicity, and culture; faith; immigration status; geography/residence; gender identity; sexual orientation; socioeconomic status/class; and ability status.

Community ethnic density, ethnic segregation, and ethnic minorities' common mental disorders in the UK

Studies in the UK demonstrate evidence that ethnic minorities living in communities with a higher proportion of co-ethnics report better mental health: co-ethnic density effects. This paper aims to address three gaps in this literature. Firstly, most UK research has focused on acute mental disorders (e.g., psychosis), with little work examining co-ethnic density effects for more common mental disorders. Secondly, there is a paucity of research exploring the role that residential segregation may play alongside co-ethnic density in minority mental health. Thirdly, little systematic testing has examined at what geographic-scale co-ethnic density effects are most salient for minority-group mental health. To address these potential gaps, we apply multi-level linear regression modelling to a large-scale, nationally-representative UK panel dataset, containing an ethnic minority booster-sample, to study the community-level drivers of mental health-related quality-of-life (SF-12 Mental Component Summary Score). The results demonstrate mixed support for the protective-effects of co-ethnic density on mental well-being. However, they demonstrate broadly consistent support for the impact of residential segregation on mental well-being. In particular, that segregation exerts a non-linear effect: mental well-being is at its most positive at medium-levels of segregation, somewhat more negative at low-levels of segregation, and much more negative at higher-levels of segregation. These patterns are present for the 'all ethnic minority' sample, and stronger for Black sub-groups compared to Asian sub-groups. These relationships appear most consistent at meso-local geographic scales (Middle Super Output Areas). These findings have important implications for theorising our understanding of the nexus between the community and mental health among minority-groups.

The ethnic density effect in psychosis: a systematic review and multilevel meta-analysis

BACKGROUND

An 'ethnic' or 'group' density effect in psychosis has been observed, whereby the risk of psychosis in minority group individuals is inversely related to neighbourhood-level proportions of others belonging to the same group. However, there is conflicting evidence over whether this effect differs between minority groups and limited investigation into other moderators.

AIMS

To conduct a comprehensive systematic review and meta-analysis of the group density effect in psychosis and examine moderators.

METHOD

Four databases were systematically searched. A narrative review was conducted and a three-level meta-analysis was performed. The potential moderating effect of crudely and specifically defined minority groups was assessed. Country, time, area size and whether studies used clinical or non-clinical outcomes were also tested as moderators.

RESULTS

Thirty-two studies were included in the narrative review and ten in the meta-analysis. A 10 percentage-point decrease in own-group density was associated with a 20% increase in psychosis risk (OR = 1.20, 95% CI 1.09-1.32, P < 0.001). This was moderated by crudely defined minority groups (F6,68 = 6.86, P < 0.001), with the strongest associations observed in Black populations, followed by a White Other sample. Greater heterogeneity was observed when specific minority groups were assessed (F25,49 = 7.26, P < 0.001).

CONCLUSIONS

This is the first review to provide meta-analytic evidence that the risk of psychosis posed by lower own-group density varies across minority groups, with the strongest associations observed in Black individuals. Heterogeneity in effect sizes may reflect distinctive social experiences of specific minority groups. Potential mechanisms are discussed, along with the implications of findings and suggestions for future research.

A narrative review of intervention in first-episode affective psychoses

While first-episode schizophrenia has received extensive attention in the literature, few studies have focused on the first episode of affective psychoses. Considering the lack of structured data regarding this diagnostic grouping commonly used in clinical settings, our aim was to scope the literature on first-episode affective psychoses to consolidate current knowledge and to identify areas to be targeted in future studies. We also planned to investigate the relevance of the "affective psychosis" concept regarding diagnostic categories and specific needs of intervention. We conducted a search on the Embase, Medline, PubMed, PsycINFO and Web Of Science databases until October 2020. We selected studies and synthesized the key findings into a narrative review regarding major topics of early intervention research: diagnostic categorization, premorbid factors, intervention, duration of untreated illness, neurobiology and neurocognition. After screening 961 titles and abstracts and 193 full-text papers, we selected 77 studies for inclusion. Our results showed heterogeneity in diagnosis-related grouping under the concept of affective psychoses, especially variability regarding the inclusion of schizoaffective disorder. Nonetheless, this concept still encompasses patients with different psychopathological and neurocognitive profiles from the non-affective patients requiring specialized intervention. This study thus provided support for the relevance of this concept as well as a need for further investigation.

Expanding the Reach of Research: Quantitative Evaluation of a Web-Based Approach for Remote Recruitment of People Who Hear Voices

Background

Similar to other populations with highly stigmatized medical or psychiatric conditions, people who hear voices (ie, experience auditory verbal hallucinations [AVH]) are often difficult to identify and reach for research. Technology-assisted remote research strategies reduce barriers to research recruitment; however, few studies have reported on the efficiency and effectiveness of these approaches.

Objective

This study introduces and evaluates the efficacy of technology-assisted remote research designed for people who experience AVH.

Methods

Our group developed an integrated, automated and human complementary web-based recruitment and enrollment apparatus that incorporated Google Ads, web-based screening, identification verification, hybrid automation, and interaction with live staff. We examined the efficacy of that apparatus by examining the number of web-based advertisement impressions (ie, number of times the web-based advertisement was viewed); clicks on that advertisement; engagement with web-based research materials; and the extent to which it succeeded in representing a broad sample of individuals with AVH, assessed through the self-reported AVH symptom severity and demographic representativeness (relative to the US population) of the sample recruited.

Results

Over an 18-month period, our Google Ads advertisement was viewed 872,496 times and clicked on 11,183 times. A total amount of US $4429.25 was spent on Google Ads, resulting in 772 individuals who experience AVH providing consent to participate in an entirely remote research study (US $0.40 per click on the advertisement and US $5.73 per consented participant) after verifying their phone number, passing a competency screening questionnaire, and providing consent. These participants reported high levels of AVH frequency (666/756, 88.1% daily or more), distress (689/755, 91.3%), and functional interference (697/755, 92.4%). They also represented a broad sample of diversity that mirrored the US population demographics. Approximately one-third (264/756, 34.9%) of the participants had never received treatment for their AVH and, therefore, were unlikely to be identified via traditional clinic-based research recruitment strategies.

Conclusions

Web-based procedures allow for time saving, cost-efficient, and representative recruitment of individuals with AVH and can serve as a model for future studies focusing on hard-to-reach populations.

Temporal variation in the incidence of treated psychotic disorders in young people

INTRODUCTION

The incidence of psychotic disorders varies between geographical areas, however less is known about whether it varies over time in the same region. Analyzing this temporal variation of incidence could improve the allocation of healthcare resources and our understanding of the aetiology of psychotic disorders. This study aimed to determine whether there was a change in the incidence of psychotic disorders over a six-year period.

METHODS

Young people aged 15 to 24 presenting with a first episode of psychosis (FEP) attending an early intervention service in Melbourne between 2011 and 2016 were included. The population at-risk was determined from the two corresponding census periods and analyses were adjusted for age, sex and migrant status.

RESULTS

A total of 1217 young people presented with a FEP over the six-year period and the crude incidence rate in 2011 was 102.4 per 100,000 population at-risk, compared to 125.4 in 2016. There was an increase in the incidence by 33% in 2015 (aIRR = 1.33, 95% CI 1.09-1.63) and 28% in 2016 (aIRR = 1.28, 95% CI 1.05-1.56). When examined according to diagnostic groups, there was an increase in the incidence of substance-induced psychotic disorders among females in 2015 (aIRR = 4.62, 95% CI 1.02-20.8).

DISCUSSION

This study shows significant temporal variations in the incidence of treated psychotic disorders. These findings demonstrate that early intervention services should continually monitor incidence case numbers and funding should be provided accordingly, to ensure the required intensive and comprehensive treatments can be sustained.

Third external replication of an individualised transdiagnostic prediction model for the automatic detection of individuals at risk of psychosis using electronic health records

BACKGROUND

Primary indicated prevention is a key target for reducing the incidence and burden of schizophrenia and related psychotic disorders. An individualised, clinically-based transdiagnostic model for the detection of individuals at risk of psychosis has been developed and validated in two large, urban healthcare providers. We tested its external validity in a geographically and demographically different non-urban population.

METHOD

Retrospective EHR cohort study. All individuals accessing secondary healthcare provided by Oxford Health NHS Foundation Trust between 1st January 2011 and 30th November 2019 and receiving a primary index diagnosis of a non-psychotic or non-organic mental disorder were considered eligible. The previously developed model was applied to this database and its external prognostic accuracy was measured with Harrell's C.

FINDINGS

The study included n = 33,710 eligible individuals, with an average age of 27.7 years (SD = 19.8), mostly white (92.0%) and female (57.3%). The mean follow-up was 1863.9 days (SD = 948.9), with 868 transitions to psychosis and a cumulative incidence of psychosis at 6 years of 2.9% (95%CI: 2.7-3.1). Compared to the urban development database, Oxford Health was characterised by a relevant case mix, lower incidence of psychosis, different distribution of baseline predictors, higher proportion of white females, and a lack of specialised clinical services for at risk individuals. Despite these differences the model retained an adequate prognostic performance (Harrell's C = 0.79, 95%CI: 0.78-0.81), with no major miscalibration.

INTERPRETATION

The transdiagnostic, individualised, clinically-based risk calculator is transportable outside urban healthcare providers. Further research should test transportability of this risk prediction model in an international setting.

Anxiety and Depression in Patients With Pulmonary Arterial Hypertension in Northwest China: A Cross-Sectional Study

OBJECTIVE

Pulmonary arterial hypertension (PAH) is a rare life-threatening and incurable disease. Although symptoms of depression and anxiety have been widely reported, these traits and associated factors have not been systematically assessed in Northwest China.

METHODS

A cross-sectional study was conducted between March 2020 and February 2021. 106 PAH patients in Northwest China were evaluated by Self-rating Anxiety Scale (SAS) and the Self Rating Depression Scale (SDS) questionnaire.

RESULTS

Overall, the included patients had particularly high depressive symptoms (70.09%), while anxiety among them was 17.55%. Multivariate linear regression revealed that patients with lower age (p = 0.04), female (p < 0.01), smoking (p < 0.01), WHO functional class III/IV (p < 0.01), higher mean pulmonary hypertension (p < 0.01), lower left ventricular ejection fraction (p < 0.01), and lower 6-min walking distance (p < 0.01) had higher anxiety scores. Patients who lived in rural areas (p = 0.01), smoking (p < 0.01), WHO functional class III/IV (p < 0.01), higher mean pulmonary hypertension (p = 0.04), lower 6-min walking distance (p < 0.01), and college degree or above had higher depression scores (p = 0.02).

CONCLUSIONS

Mental health problems such as depression are common among patients with PAH in Northwest China. Patients' characteristics such as smoking status, WHO functional class, and 6-min walking distance were related to anxiety and depression scores. Thus, early detection of mental health problems such as depression and anxiety should be detected in PAH patients. Meanwhile, interventions against these problems should be used to improve such patients' mental status.

The psychosis analysis in real-world on a cohort of large-scale patients with schizophrenia

Background

With China experiencing unprecedented economic development and social change over the past three decades, Chinese policy makers and health care professionals have come to view mental health as an important outcome to monitor. Our study conducted an epidemiological study of psychosis in Guangdong province, with 20 million real-world follow-up records in the last decade.

Methods

Data was collected from Guangdong mental health information platform from 2010 to 2019, which had standardized disease registration and follow-up management for nearly 600,000 patients with six categories of mental diseases and 400,000 patients with schizophrenia. We conducted clinical staging for the disease course of the patients and divided the data with various factors into different stages of disease. Quantitative analysis was utilized to investigate the high relevant indicators to the disease. The results were projected on geography map for regional distribution analysis.

Results

The majority cases of mental disease incidence were between the age of 15 and 29, while the peak age for both male and female was between 20 to 24 years old. The disease course with the largest number of patients’ cases was between 5 to 10 years. The therapeutic effect of patients gradually decreased with the development of disease course, while the risk increased with the disease course. The analysis of influencing factors showed that poor economic conditions incurred higher risk scores, and good medication adherence was effective in improving treatment outcomes. In addition, receiving good education contributed to the reduction of the risk of schizophrenia and the improvement of the efficiency of early treatment. Through the analysis of regional distribution of schizophrenia disease, developed economic conditions and favorable resource conditions could promote the reduction of disease risk, while in economically backward regions, it often accompanied with lower therapeutic effect and higher disease risk.

Conclusions

Certain demographic factors had a relatively prominent impact on the therapeutic effect and risk of schizophrenia, such as high-quality medication adherence. Therapeutic effect and risk were highly correlated. Backward economic conditions often associated with poor efficacy and higher risk assessment, and the developed economy and better medical resource are beneficial for the treatment of psychotic.

Personality disorder in an Early Intervention Psychosis cohort: Findings from the Social Epidemiology of Psychoses in East Anglia (SEPEA) study

AIM

Personality Disorders (PD) often share clinical and phenomenological overlap with psychotic disorders, especially at onset. However, there is little research on comorbid PD among people experiencing first episode psychosis. We examined the prevalence of PD recording and its sociodemographic and clinical correlates in people accepted to Early Intervention in Psychosis (EIP) services.

METHODS

Participants were aged 16-35, accepted into 6 EIP services for suspected psychosis, as part of the Social Epidemiology of Psychoses in East Anglia (SEPEA) study. PD was recorded by clinicians according to ICD-10. Multilevel logistic regression was performed.

RESULTS

Of 798 participants, 76 people (9.5%) received a clinical diagnosis of PD, with emotionally unstable PD (75.0%, N = 57) the most common subtype. In multivariable analysis, risk factors for PD included female sex (odds ratio [OR]: 3.4; 95% CI: 2.0-5.7), absence of psychotic disorder after acceptance to EIP (OR: 3.0; 95% CI: 1.6-5.5), more severe hallucinations (OR: 1.6; 95% CI: 1.2-2.1), and lower parental SES (OR: 1.4; 95% CI: 1.1-1.8). Compared with the white British, black and minority ethnic groups were less likely to receive a PD diagnosis (OR: 0.3; 95% CI: 0.1-0.7). There was no association between PD and neighbourhood-level deprivation or population-density.

CONCLUSIONS

Recording of a PD diagnosis was three times more common amongst participants later found not to meet threshold criteria for psychotic disorder, implying phenomenological overlap at referral which highlights difficulties encountered in accurate diagnostic assessment, treatment and onward referral. People with PD experienced more individual-level, but not neighbourhood-level social disadvantage in an already disadvantaged sample.

Organization framework and preliminary findings from the Athens First-Episode Psychosis Research Study

AIMS

Athens First-Episode Psychosis (FEP) Research study, aims to explore the potential associations between multiple genetic, environmental and neurometabolic risk factors of psychotic disorders, through the clinical management of FEP patients with minimal exposure (<2 weeks) to antipsychotic treatment at entry. The goal of this paper is to introduce the background, rationale and design of the study and present its preliminary findings.

METHODS

We developed a longitudinal cohort study of FEP patients 16-45 years old, presenting at the emergency units of five psychiatric hospitals across Athens, Greece. Research timeline includes baseline, 1-month and 1-year follow-up. Clinical, genetic, environmental, cognitive and biochemical parameters are measured, using psychometric tools, clinical interviews and laboratory tests. A descriptive analysis of baseline and 1-month assessments was performed including demographic characteristics, family history, medication, clinical picture, traumatic experiences, drug use and cognitive functioning.

RESULTS

During the last 3 years, 130 subjects have been enrolled in the study. Data so far reveal that, despite the severity of baseline presentation, at 1-month the majority (57.4%) met the Andreasen symptom severity criteria for remission, without the time criterion and showed mild functional improvement. Several environmental adversities and poor cognitive performance were identified, which need to be further elaborated.

CONCLUSIONS

Athens FEP Research study is the first gene-environment interaction study in Greece. In this article we introduce the organization and methodological framework of the project, along with its basic initial findings. Future analysis will allow the validation of tractable predictors and risk factors implicated in the development and outcome of psychosis.

Neighborhood-level predictors of age at onset and duration of untreated psychosis in first-episode psychotic disorders

OBJECTIVE

Recent years have witnessed growing interest in the role of the social environment in the development and outcomes of schizophrenia. We investigated whether neighborhood characteristics are associated with two important prognostic factors in early-course psychosis, age at onset of psychosis (AOP) and duration of untreated psychosis (DUP).

METHODS

Data were collected from patients admitted to the hospital for first-episode schizophrenia-spectrum disorder. We collected data on perceived neighborhood disorder during childhood/adolescence and extracted data on 13 neighborhood characteristics from the American Community Survey based upon individual addresses. Four neighborhood-level factors were derived from factor analysis. Multiple logistic regression analyses assessed the association between specific neighborhood characteristics and the two prognostic factors (earlier AOP and longer DUP) in early-course psychosis.

RESULTS

143 participants had valid addresses geo-coded. Neighborhood-level residential instability was associated with an earlier AOP (OR = 1.760; p = 0.022) even after controlling for known risk factors (OR = 2.026; p = 0.020) and also after controlling for individual-level residential instability (OR = 1.917; p = 0.037). The general socioeconomic status neighborhood factor (OR = 1.119; p = 0.019) and perceived neighborhood disorder (OR = 1.075; p = 0.005) were associated with a longer DUP. But only perceived neighborhood disorder (OR = 1.146; p = 0.011) remained significant, and general socioeconomic status was close to significant (OR = 1.215; p = 0.062), after controlling for individual-level predictors and socioeconomic status.

CONCLUSIONS

This study found evidence that neighborhood-level characteristics (in this case, residential instability) may be associated with earlier AOP, and perceptions of neighborhood disorder are associated with a longer treatment delay. Socioenvironmental factors should be more consistently considered going forward in research on early psychotic disorders.

Prevalence of mental illness in primary care and its association with deprivation and social fragmentation at the small-area level in England

BACKGROUND

We aimed to spatially describe mental illness prevalence in England at small-area geographical level, as measured by prevalence of depression, severe mental illness (SMI) and antidepressant prescription volume in primary care records, and how much of their variation was explained by deprivation, social fragmentation and sociodemographic characteristics.

METHODS

Information on prevalence of depression and SMI was obtained from the Quality and Outcomes Framework (QOF) administrative dataset for 2015/16 and the national dispensing dataset for 2015/16. Linear regression models were fitted to examine ecological associations between deprivation, social fragmentation, other sociodemographic characteristics and mental illness prevalence.

RESULTS

Mental illness prevalence varied within and between regions, with clusters of high prevalence identified across England. Our models explained 33.4-68.2% of variability in prevalence, but substantial variability between regions remained after adjusting for covariates. People in socially cohesive and socially deprived areas were more likely to be diagnosed with depression, while people in more socially fragmented and more socially deprived areas were more likely to be diagnosed with SMI.

CONCLUSIONS

Our findings suggest that to tackle mental health inequalities, attention needs to be targeted at more socially deprived localities. The role of social fragmentation warrants further investigation, and it is possible that depression remains undiagnosed in more socially fragmented areas. The wealth of routinely collected data can provide robust evidence to aid optimal resource allocation. If comparable data are available in other countries, similar methods could be deployed to identify high prevalence clusters and target funding to areas of greater need.

The Incidence of Nonaffective, Nonorganic Psychotic Disorders in Older People: A Population-based Cohort Study of 3 Million People in Sweden

BACKGROUND

There are limited data on the epidemiology of very late-onset schizophrenia-like psychosis (VLOSLP) and how this relates to potential risk factors including migration, sensory impairment, traumatic life events, and social isolation.

METHODS

We followed up a cohort of 3 007 378 people living in Sweden, born 1920-1949, from their 60th birthday (earliest: January 15, 1980) until December 30 2011, emigration, death, or first recorded diagnosis of nonaffective psychosis. We examined VLOSLP incidence by age, sex, region of origin, income, partner or child death, birth period, and sensory impairments.

RESULTS

We identified 14 977 cases and an overall incidence of 37.7 per 100 000 person-years at-risk (95% CI = 37.1-38.3), with evidence that rates increased more sharply with age for women (likelihood ratio test: χ2(6) = 31.56, P < .001). After adjustment for confounders, rates of VLOSLP were higher among migrants from Africa (hazard ratio [HR] = 2.0, 95% CI = 1.4-2.7), North America (HR = 1.4, 95% CI = 1.0-1.9, P = .04), Europe (HR = 1.3, 95% CI = 1.2-1.4), Russian-Baltic regions (HR = 1.6, 95% CI = 1.4-1.9), and Finland (HR = 1.6, 95% CI = 1.5-1.7). VLOSLP risk was highest for those in the lowest income quartile (HR = 3.1, 95% CI = 2.9-3.3). Rates were raised in those whose partner died 2 years before cohort exit (HR = 1.1, 95% CI = 1.0-1.3, P = .02) or whose child died in infancy (HR = 1.2, 95% CI = 1.0-1.4, P = .05), those without a partner (HR = 1.9, 95% CI = 1.8-1.9) or children (HR = 2.4, 95% CI = 2.3-2.5), and those whose child had a psychotic disorder (HR = 2.4, 95% CI = 2.2-2.6).

INTERPRETATION

We identified a substantial burden of psychosis incidence in old age, with a higher preponderance in women and most migrant groups. Life course exposure to environmental factors including markers of deprivation, isolation, and adversity were associated with VLOSLP risk.

Rural birth/upbringing and childhood adversities are associated with psychotic experiences in university students in China

BACKGROUND

Urbanicity has been reported to associate with an increased risk of psychotic experiences (PEs) in developed countries but less is known about the situation in developing countries. The present study aimed to investigate the effects of birth/upbringing place and other environmental factors on PEs in Chinese university students.

METHODS

A computer-assisted cross-sectional survey was conducted on 4620 second-year undergraduates, using a stratified cluster sampling. Birth places and residential mobility before 16 years old were recorded. PEs were measured using the subscales of psychoticism and paranoid ideation in the Symptom Checklist-90-R (SCL-90-R). Six questions extracted from the childhood section of the World Mental Health Composite International Diagnostic Interview (WMH-CIDI) were used to assess childhood trauma.

RESULTS

Generalized ordered logit model of multiple regression analysis revealed that participants with rural birth/upbringing (e.g. rural upbringing, on graded factor score of psychoticism and paranoid ideation [GFSPPI], 0 versus 1 & 2, odds ratio [OR] 1.409, 95% CI 1.219-1.628, p < 0.00001; 0 & 1 versus 2, OR 1.584, 95% CI 1.179-2.128, p < 0.00001) and those who reported childhood trauma (e.g. on GFSPPI, 0 versus 1 & 2, OR 1.737, 95% CI 1.498-2.014, p < 0.00001; 0 & 1 versus 2, OR 1.618, 95% CI 1.224-2.140, p < 0.00001) were apt to present more severe PEs. While upbringing places and childhood trauma affected both the presence and the severity of PEs, gender affected the presence or absence of PEs only (e.g. females, on GFSPPI, 0 versus 1 & 2, OR 1.887, 95% CI 1.631-2.183, p < 0.00001; 0 & 1 versus 2, OR 0.927, 95% CI 0.702-1.223, p = 0.593). Besides, the number of risk factors was associated with the severity of PEs in the cumulative odds logistic regression analysis (e.g. 3 risk factors versus 0 risk factor, on GFSPPI, OR 4.126, 95% CI 3.075-5.537, p < 0.00001).

CONCLUSIONS

Female, rural birth/upbringing and childhood trauma are risk factors of PEs in university students in China. The discrepancy in the findings between developed countries and China has important implications for urbanicity as a risk factor for PEs.

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.

Psychosis and urbanicity: a review of the recent literature from epidemiology to neurourbanism

PURPOSE OF REVIEW

Epidemiological studies associate city living with an elevated psychosis risk. Urban (social/economic) stress and exposure to environmental toxins, pollution or disease agents have been proposed to underlie this association. This review provides an update on the recent evidence (May 2017 - November 2018).

RECENT FINDINGS

Of 647 screened studies, 17 on: urbanicity-psychosis associations in worldwide high, middle and low-income countries; explanatory mechanisms, including nature exposure, social and economic stressors and genetic risk; urbanicity effects on the brain and coping; and urbanicity and resources, were included. The reviewed evidence revealed complex patterns of urbanicity-psychosis associations with considerable international variation within Europe and between low, middle and high-income countries worldwide. Social and economic stressors (e.g. migration, ethnic density and economic deprivation), nature exposure and access to resources could only explain part of the urbanicity effects. Risk factors differed between countries and between affective and non-affective psychosis.

SUMMARY

Urbanicity-psychosis associations are heterogeneous and driven by multiple risk and protective factors that seem to act differently in different ethnic groups and countries. Interdisciplinary research combining approaches, for example from experimental neuroscience and epidemiology, are needed to unravel specific urban mechanisms that increase or decrease psychosis risk.

A new hope for early psychosis care: the evolving landscape of digital care tools

Improving understanding of and outcomes for early-course psychosis (ECP) is a recognised global mental health priority. We argue digital health technologies can advance care for ECP by better accounting for clinical heterogeneity, offering better predictive models, increasing access to early interventions and enhancing existing treatment options.Declaration of interestL.M.T. owns shares in Safari Health Inc - a digital health technology company.

Psychoses sans Frontieres: towards an interdisciplinary understanding of psychosis risk amongst migrants and their descendants

Understanding the excess risk of psychotic disorders in migrant and ethnic minority groups has long been an important research focus in psychiatric epidemiology and public mental health. Heterogeneity between migrant groups based on the region of origin, minority status and other socioeconomic factors may provide clues as to the underlying aetiological mechanisms explaining this risk, as well as informing our general understanding of psychotic disorders. Nonetheless, disentangling the mechanisms underlying this association has been the focus of more speculation and theory to date than empirical research. Now more than ever, we need to move beyond studies which demonstrate excess rates in migrant and ethnic minority groups to novel population-based studies which identify the determinants and mechanisms through which this risk is shaped. In this paper, we review the main hypotheses proposed to explain these disparities and the current level of support for them. We then highlight recent evidence from epidemiology and neuroscience which provides important new clues in our understanding of the aetiology of psychotic disorders. We concluded with suggestions for future interdisciplinary research to prevent this public mental health inequality within a generation.

Association of Residential Mobility Over the Life Course With Nonaffective Psychosis in 1.4 Million Young People in Sweden

IMPORTANCE

Residential mobility (changing residence) during childhood and early adolescence is a possible risk factor for several adverse health outcomes, including psychotic disorders. However, it is unclear whether sensitive periods to residential mobility exist over the life course, including in adulthood, or if greater moving distances, which might disrupt social networks, are associated with a greater psychosis risk.

OBJECTIVE

To examine the association between residential mobility over the life course and the risk of nonaffective psychosis.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study included all people born in Sweden between January 1, 1982, and December 31, 1995, who were alive and resided in Sweden on their 16th birthday who were followed up until up to age 29 years (ending December 2011). Participants were followed until receiving a first diagnosis of an International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) nonaffective psychotic disorder (F20-29), emigration, death, or the end of 2011, whichever was sooner. National register linkage provided exposure, outcome, and covariate data (complete data were available for 1 440 383 participants [97.8%]).

EXPOSURES

The exposures to distance moved and the number of residential moves were examined for participants at the following periods over the life course: 0 to 6 years, 7 to 15 years, 16 to 19 years, and 20 years and older.

RESULTS

This study included 1 440 383 participants, of whom 4537 (0.31%) had nonaffective psychotic disorder (median age, 20.9 [interquartile range, 19.0-23.3]). More frequent moves during childhood and adolescence were associated with an increased risk of nonaffective psychosis that showed dose-response associations independent of covariates. The most sensitive period of risk occurred during late adolescence; those who moved during each year between age 16 to 19 years had an increased adjusted hazard ratio (HR) of 1.99 (95% CI, 1.30-3.05) compared with those who never moved. One move during adulthood was not associated with psychosis risk (adjusted HR, 1.04; 95% CI, 0.94-1.14), but moving 4 or more times during adulthood was associated with increased risk (adjusted hazard ratio, 1.82; 95% CI, 1.51-2.23). Independently, moving greater distances before age 16 years was associated with an increased risk (adjusted HR, 1.11; 95% CI, 1.05-1.19), with evidence of a nonlinear threshold effect for moves longer than 30 km. The distance moved after age 20 years was associated with a decreased risk (adjusted HR, 0.67; 95% CI, 0.63-0.71).

CONCLUSIONS AND RELEVANCE

Children and adolescents with less disruption in their residential environments are less likely to experience psychotic disorders in early adulthood. Moves that may necessitate changes in school and social networks were most strongly associated with future risk.

Association of Urbanicity With Psychosis in Low- and Middle-Income Countries

Importance

Urban residence is one of the most well-established risk factors for psychotic disorder, but most evidence comes from a small group of high-income countries.

Objective

To determine whether urban living is associated with greater odds for psychosis in low- and middle-income countries (LMICs).

Design, Setting, and Participants

This international population-based study used cross-sectional survey data collected as part of the World Health Organization (WHO) World Health Survey from May 2, 2002, through December 31, 2004. Participants included nationally representative general population probability samples of adults (≥18 years) residing in 42 LMICs (N = 215 682). Data were analyzed from November 20 through December 5, 2017.

Exposures

Urban vs nonurban residence, determined by the WHO based on national data.

Main Outcomes and Measures

Psychotic experiences, assessed using the WHO Composite International Diagnostic Interview psychosis screen, and self-reported lifetime history of a diagnosis of a psychotic disorder.

Results

Among the 215 682 participants (50.8% women and 49.2% men; mean [SD] age, 37.9 [15.7] years), urban residence was not associated with psychotic experiences (odds ratio [OR], 0.99; 95% CI, 0.89-1.11) or psychotic disorder (OR, 0.89; 95% CI, 0.76-1.06). Results of all pooled analyses and meta-analyses of within-country effects approached a null effect, with an overall OR of 0.97 (95% CI, 0.87-1.07), OR for low-income countries of 0.98 (95% CI, 0.82-1.15), and OR for middle-income countries of 0.96 (95% CI, 0.84-1.09) for psychotic experiences and an overall OR of 0.92 (95% CI, 0.73-1.16), OR for low-income countries of 0.92 (95% CI, 0.66-1.27), and OR for middle-income countries of 0.92 (95% CI, 0.67-1.27) for psychotic disorder.

Conclusions and Relevance

Our results provide evidence that urbanicity, a well-established risk factor for psychosis, may not be associated with elevated odds for psychosis in developing countries. This finding may provide better understanding of the mechanisms by which urban living may contribute to psychosis risk in high-income countries, because urban-rural patterns of cannabis use, racial discrimination, and socioeconomic disparities may vary between developing and developed nations.