Prenatal and perinatal complications are established risk factors for psychotic disorder, but far less is known about these measures and psychotic experiences (PEs). We investigated the longitudinal effect of prenatal risk factors (maternal behavior, medication complications) and perinatal risk factors (birth weight, medical complications) on frequency of PEs. We also examined the cumulative risk of prenatal/perinatal risk factors, and differences between transient PE, persistent PE, and controls.

The Adolescent Brain Cognitive Development study is a large child cohort (age 9–10 at baseline; n = 11 872 with PE data). PEs were measured longitudinally using the Prodromal Questionnaire-Brief, Child version, and included only if reported as distressing. Mixed-effects models were used for analysis, controlling for random effects, and a substantial number of fixed-effects covariates.

Urinary tract infection (β = 0.11, 95% confidence interval [CI] 0.03–0.19) and severe anemia (β = 0.18, 95% CI 0.07–0.29) increased frequency of distressing PEs in childhood. Number of prenatal complications increased frequency of PEs (β = 0.03, 95% CI 0.01–0.06) and risk of persistent PEs (odds ratio [OR] = 1.08, 95% CI 1.01–1.15). Maternal smoking was associated with an increased frequency of PEs (β = 0.11, 95% CI 0.04–0.18) and persistent PEs (OR = 1.31, 95% CI 1.04–1.66). Maternal substance use was a risk factor for a 48% increased risk of persistent PEs (OR = 1.48, 95% CI 1.08–2.01). Perinatal complications showed no effect on PEs.

This study provides evidence that certain prenatal medical complications (severe nausea, severe anemia), cumulative number of prenatal medical complications, and maternal behaviors (smoking during pregnancy), increased frequency of distressing PEs in childhood. Maternal smoking and substance use, as well as cumulative number of prenatal complications increased risk of persistent PEs.

There is limited evidence as to whether the immune protein profile is associated with a particular symptomatology pattern across the psychosis continuum.

We estimated two bifactor models of general and specific dimensions of psychotic experiences in unaffected siblings of patients (n = 52) and community controls (n = 200), and of psychotic symptoms in first-episode psychosis (FEP) patients (n = 110). We evaluated associations between these transdiagnostic dimensions and trait (TNF-α, IFN-γ), state (IL-6, IL-1β), and regulatory (TGF-β, IL-10, IL-4) cytokines. We explored whether schizophrenia genetic liability (schizophrenia polygenic risk score; SZ-PRS) modified the associations.

High levels of trait marker IFN-γ were associated with the severity of general psychosis dimension in the unaffected siblings and community controls, expanding to the depressive dimension in siblings and to the manic dimension in FEP. High TNF-α levels were associated with more positive psychotic experiences in unaffected siblings and manic symptoms in FEP. Low levels of state markers IL-6 and IL-1β were observed in unaffected siblings presenting more depressive experiences. Still, high levels of IL-6 and IL-1β were associated with the severity of the depressive and negative symptom dimensions at FEP. The severity of transdiagnostic dimension scores across the three groups was associated with lower regulatory cytokines. Exploratory analysis suggested that a high SZ-PRS contributed mostly to associations with psychotic dimensions.

IFN-γ mapped onto the multidimensional expression of psychosis, reinforcing the trait concept. State markers IL-6 and IL-1β may fluctuate along the spectrum. Dysfunction in the regulatory arm may disinhibit the inflammatory system. Associations with psychotic dimensions may be more prone to SZ-PRS susceptibility.

Incidence of first-episode psychosis (FEP) varies substantially across geographic regions. Phenotypes of subclinical psychosis (SP), such as psychotic-like experiences (PLEs) and schizotypy, present several similarities with psychosis. We aimed to examine whether SP measures varied across different sites and whether this variation was comparable with FEP incidence within the same areas. We further examined contribution of environmental and genetic factors to SP.

We used data from 1497 controls recruited in 16 different sites across 6 countries. Factor scores for several psychopathological dimensions of schizotypy and PLEs were obtained using multidimensional item response theory models. Variation of these scores was assessed using multi-level regression analysis to estimate individual and between-sites variance adjusting for age, sex, education, migrant, employment and relational status, childhood adversity, and cannabis use. In the final model we added local FEP incidence as a second-level variable. Association with genetic liability was examined separately.

Schizotypy showed a large between-sites variation with up to 15% of variance attributable to site-level characteristics. Adding local FEP incidence to the model considerably reduced the between-sites unexplained schizotypy variance. PLEs did not show as much variation. Overall, SP was associated with younger age, migrant, unmarried, unemployed and less educated individuals, cannabis use, and childhood adversity. Both phenotypes were associated with genetic liability to schizophrenia.

Schizotypy showed substantial between-sites variation, being more represented in areas where FEP incidence is higher. This supports the hypothesis that shared contextual factors shape the between-sites variation of psychosis across the spectrum.

Psychotic experiences (PEs) and social isolation (SI) seem related during early stages of psychosis, but the temporal dynamics between the two are not clear. Literature so far suggests a self-perpetuating cycle wherein momentary increases in PEs lead to social withdrawal, which, subsequently, triggers PEs at a next point in time, especially when SI is associated with increased distress. The current study investigated the daily-life temporal associations between SI and PEs, as well as the role of SI-related and general affective distress in individuals at clinical high risk (CHR) for psychosis.

We used experience sampling methodology in a sample of 137 CHR participants. We analyzed the association between SI, PEs, and distress using time-lagged linear mixed-effects models.

SI did not predict next-moment fluctuations in PEs, or vice versa. Furthermore, although SI-related distress was not predictive of subsequent PEs, general affective distress during SI was a robust predictor of next-moment PEs.

Our results suggest that SI and PEs are not directly related on a moment-to-moment level, but a negative emotional state when alone does contribute to the risk of PEs. These findings highlight the role of affective wellbeing during early-stage psychosis development.

Psychotic disorders are highly heritable, yet the evidence is less clear for subclinical psychosis expression, such as psychotic experiences (PEs). We examined if PEs in parents were associated with PEs in offspring.

As part of the Danish general population Lolland-Falster Health Study, families with youths aged 11–17 years were included. Both children and parents reported PEs according to the Psychotic Like Experiences Questionnaire, counting only ‘definite’ PEs. Parents additionally reported depressive symptoms, anxiety, and mental wellbeing. The associations between parental and child PEs were estimated using generalized estimating equations with an exchangeable correlation structure to account for the clustering of observations within families, adjusting for sociodemographic characteristics.

Altogether, 984 youths (mean age 14.3 years [s.d. 2.0]), 700 mothers, and 496 fathers from 766 households completed PEs-questionnaires. Offspring of parents with PEs were at an increased risk of reporting PEs themselves (mothers: adjusted risk ratio (aRR) 2.42, 95% CI 1.73–3.38; fathers: aRR 2.25, 95% CI 1.42–3.59). Other maternal problems (depression, anxiety, and poor mental well-being), but not paternal problems, were also associated with offspring PEs. In multivariate models adjusting for parental problems, PEs, but not other parental problems, were robustly associated with offspring PEs (mothers: aRR 2.25, 95% CI 1.60–3.19; fathers: aRR 2.44, 95% CI 1.50–3.96).

The current findings add novel evidence suggesting that specific psychosis vulnerability in families is expressed at the lower end of the psychosis continuum, underlining the importance of assessing youths’ needs based on psychosis vulnerability broadly within the family systems.

Psychotic disorders develop gradually along a continuum of severity. Understanding factors associated with psychosis development, such as sleep, could aid in identification of individuals at elevated risk. This study aimed to assess (1) the dynamic relationship between psychotic experiences (PEs) and sleep quality and quantity, and (2) whether this relationship differed between different clinical stages along the psychosis continuum.

We used daily diary data (90 days) of individuals (N = 96) at early stages (i.e. before a first diagnosis of psychosis) along the psychosis continuum. Multilevel models were constructed with sleep quality and sleep quantity as predictors of PEs and vice versa. Post-hoc, we constructed a multilevel model with both sleep quality and quantity as predictors of PEs. In addition, we tested whether associations differed between clinical stages.

Within persons, poorer sleep predicted next day PEs (B = −0.02, p = 0.01), but not vice versa. Between persons, shorter sleep over the 90-day period predicted more PEs (B = −0.04, p = 0.002). Experiencing more PEs over 90-days predicted poorer (B = −0.02, p = 0.02) and shorter (B = −1.06, p = 0.008) sleep. We did not find any significant moderation effects for clinical stage.

We found a bidirectional relationship between sleep and PEs with daily fluctuations in sleep predicting next day PEs and general patterns of more PEs predicting poorer and shorter sleep. Our results highlight the importance of assessing sleep as a risk marker in the early clinical stages for psychosis.

Exposure to adversities in early childhood is associated with psychotic experiences and disorders in adulthood. We aimed to examine whether early childhood adversities are associated with middle childhood psychotic experiences in a cohort of children at familial high risk of schizophrenia (FHR-SZ), bipolar disorder (FHR-BP) and population-based controls (controls).

Four hundred and forty-six children from The Danish High Risk and Resilience Study – VIA7 and VIA11 participated in this study (FHR-SZ = 170; FHR-BP = 103; controls = 173). Exposure to early childhood adversities and psychotic experiences were assessed using face-to-face interviews. Having childhood adversities assessed at baseline (age 7) was used as predictor. Psychotic experiences assessed at follow-up (age 11) were used as outcome.

Across the sample, exposure to early childhood interpersonal adversities was associated with an increased risk for any middle childhood psychotic experiences and subclinical delusions when adjusting for relevant confounders (OR 1.8, 95% CI 1.0–3.1, p = 0.05; OR 3.0, 95% CI 1.6–5.6, p < 0.001). There was no significant dose–response effect of exposure to multiple types of childhood adversities on any psychotic experiences. There were no interaction effects between early childhood adversities and FHR on middle childhood psychotic experiences. Exploratory analyses revealed that experiencing domestic violence in early childhood was associated with any middle childhood psychotic experiences (OR 2.8, 95% CI 1.5–5.1, p = 0.001).

Exposure to interpersonal adversities during early childhood is associated with an increased risk for middle childhood psychotic experiences including specifically subclinical delusions. Future studies should examine associations between exposure to childhood adversities and conversion to psychosis within this cohort.

Psychotic experiences and negative symptoms (PENS) are common in non-clinical populations. PENS are associated with adverse outcomes, particularly when they persist. Little is known about the trajectories of PENS dimensions in young people, nor about the precursory factors associated with these trajectories.

We conducted growth mixture modelling of paranoia, hallucinations, and negative symptoms across ages 16, 17, and 22 in a community sample (N = 12 049–12 652). We then described the emergent trajectory classes through their associations with genome-wide polygenic scores (GPS) for psychiatric and educational phenotypes, and earlier childhood characteristics.

Three trajectory classes emerged for paranoia, two for hallucinations, and two for negative symptoms. Across PENS, GPS for clinical help-seeking, major depressive disorder, and attention deficit hyperactivity disorder were associated with increased odds of being in the most elevated trajectory class (OR 1.07–1.23). Lower education GPS was associated with the most elevated trajectory class for hallucinations and negative symptoms (OR 0.77–0.91). Conversely for paranoia, higher education GPS was associated with the most elevated trajectory class (OR 1.25). Trajectory class associations were not significant for schizophrenia, obsessive-compulsive disorder, bipolar disorder, or anorexia GPS. Emotional/behaviour problems and life events in childhood were associated with increased odds of being in the most elevated trajectory class across PENS.

Our results suggest latent heterogeneity in the development of paranoia, hallucinations, and negative symptoms in young people that is associated with specific polygenic scores and childhood characteristics.

Psychotic experiences (PEs) frequently occur and are associated with a range of negative health outcomes. Prospective studies on PEs are scarce, and to date no study investigated PE prevalence, incidence, persistence, their risk indicators, and psychiatric comorbidity, in one dataset. Furthermore, most studies are based on self-report, and it is unclear how this compares to clinical interviews.

Data are used from the Netherlands Mental Health Survey and Incidence Study-2 (NEMESIS-2), a psychiatric cohort study among a representative sample of adults (baseline characteristics: N = 6646; 49.6% female; 18–64 years). Results are presented for self-reported and clinically validated PEs. Associations are assessed for mental disorders, socio-demographic, vulnerability, physical health, and substance use factors.

Based on self-report, at baseline 16.5% of respondents had at least one PE in their lifetime, of those, 30.1% also reported a PE at 3-year follow-up. 4.8% had a first PE at 3-year follow up. The 3-year prevalence of PE was associated with almost all studied risk indicators. Generally, the strongest associations were found for mental health disorders. Prevalence and incidence rates were two to three times higher in self-report than in clinical interview but results on associated factors were similar.

Validated prevalence and incidence estimates of PE are substantially lower than self-reported figures but results on associated factors were similar. Therefore, future studies on associations of PEs can rely on relatively inexpensive self-reports of PEs. The associations between PE and mental disorders underline the importance of assessment of PE in general practice.

Psychotic experiences (PE) occur most often in childhood, at the same age many mental disorders (MD) develop. There is growing evidence that those who report PE and MD show poorer health outcomes. If this occurs in psychosocial outcomes e.g. self-esteem, stress, mental distress, or social support, is under examined. Attachment anxiety and avoidance are the dimensions of attachment, which is hypothesized to develop in infancy as a mechanism for interpersonal relationships in times of need.

To examine the role of transient childhood PE in adult psychosocial outcomes, in those with and without MD. Additionally, to examine if the dimensions of attachment attenuate this model.

One hundred and three participants attended baseline (age 11 – 13) and 10-year follow-up. PE and MD were collected using the Schedule for Affective Disorders and Schizophrenia for School-aged Children, Present & Lifetime Version. Attachment and outcomes were collected using self-report measures. Analysis compared those with PE, MD and PE and MD, to healthy controls.

PE in childhood was associated with lower self-esteem and lower perceived social support from friends. Lower self-esteem in adulthood was more pronounced in those reporting PE and MD, and was additionally associated with stress in relationships, daily life, and mental distress. Childhood MD without PE was not significantly associated with any psychosocial outcomes. Attachment dimensions significantly attenuated the relationship between PE and self-esteem.

This paper illustrates the significant association of childhood PE on adult outcomes, independent of the effect of co-occurring MD, and demonstrate attachment dimensions role in this model.

No significant relationships.

Psychotic experiences (PEs) are relatively common in childhood and adolescence and are associated with increased risk of functional issues and psychiatric illness in young adulthood, and PEs that recur are associated with increased risk of poorer psychiatric and functional outcomes. Childhood adversity is a well-established risk factor for PEs. The aim of this study was to investigate (1) the relationship between childhood adversity and recurring PEs in adolescence and (2) candidate mediators of that relationship.

We used data from Cohort ‘98 of the Growing Up in Ireland study (n = 6039) at three time points (ages 9, 13 and 17) to investigate the relationship between childhood adversity (parent-reported at age 9), recurring PEs (measured using a subset of the Adolescent Psychotic-like Symptoms Screener at ages 13 and 17). The mediating roles of parent–child relationship, internalising and externalising difficulties, self-concept, physical activity, dietary quality, perceived neighbourhood safety and friendship quantity were investigated using the KHB path decomposition method.

Childhood adversity was associated with an increased risk of recurring PEs with a population attributable fraction of 23%. Internalising difficulties and self-concept explained 13% of the relationship between childhood adversity and PEs suggesting a partial mediation. A significant direct effect remained between childhood adversity and recurring PEs.

The established relationship between childhood adversity and PEs may be mainly driven by the relationship between childhood adversity and recurring PEs. Internalising difficulties and self-concept together mediate part of the relationship between childhood adversity and recurring PEs.

Social capital is thought to represent an environmental factor associated with the risk of psychotic disorder (PD). This study aims to investigate the association between neighbourhood-level social capital and clinical transitions within the spectrum of psychosis.

In total, 2175 participants, representative of a community-based population, were assessed twice (6 years apart) to determine their position within an extended psychosis spectrum: no symptoms, subclinical psychotic experiences (PE), clinical PE, PD. A variable representing change between baseline (T1) and follow-up (T2) assessment was constructed. Four dimensions of social capital (informal social control, social disorganisation, social cohesion and trust, cognitive social capital) were assessed at baseline in an independent sample, and the measures were aggregated to the neighbourhood level. Associations between the variable representing psychosis spectrum change from T1 to T2 and the social capital variables were investigated.

Lower levels of neighbourhood-level social disorganisation, meaning higher levels of social capital, reduced the risk of clinical PE onset (OR 0.300; z = −2.75; p = 0.006), persistence of clinical PE (OR 0.314; z = −2.36; p = 0.018) and also the transition to PD (OR 0.136; z = −2.12; p = 0.034). The other social capital variables were not associated with changes from T1 to T2.

Neighbourhood-level social disorganisation may be associated with the risk of psychosis expression. Whilst replication of this finding is required, it may point to level of social disorganisation as a public health target moderating population psychosis risk.

Prevention programs that are ‘transdiagnostic’ may be more cost-effective and beneficial, in terms of reducing levels of psychopathology in the general population, than those focused on a specific disorder. This randomized controlled study evaluated the efficacy of one such intervention program called Resilience Training (RT).

College students who reported mildly elevated depressive or subclinical psychotic symptoms (‘psychotic experiences' (PEs)) (n = 107) were randomized to receiving RT (n = 54) or to a waitlist control condition (n = 53). RT consists of a four-session intervention focused on improving resilience through the acquisition of mindfulness, self-compassion, and mentalization skills. Measures of symptoms and these resilience-enhancing skills were collected before and after the 4-week RT/waitlist period, with a follow-up assessment 12-months later.

Compared to the waitlist control group, RT participants reported significantly greater reductions in PEs, distress associated with PEs, depression, and anxiety, as well as significantly greater improvements in resilience, mindfulness, self-compassion, and positive affect, following the 4-week RT/waitlist period (all p < 0.03). Moreover, improvements in resilience-promoting skills were significantly correlated with symptom reductions (all p < 0.05). Lastly, the RT-related reductions in PEs and associated distress were maintained at the 12-month follow-up assessment.

RT is a brief, group-based intervention associated with improved resilience and reduced symptoms of psychopathology, with sustained effects on PEs, in transdiagnostically at-risk young adults. Follow-up studies can further assess the efficacy of RT relative to other interventions and test whether it can reduce the likelihood of developing a serious mental illness.

Rapid progression from the first identifiable symptom to the onset of first-episode psychosis (FEP) allows less time for early intervention. The aim of this study was to examine the association between the first identifiable symptom and the subsequent speed of illness progression.

Data were available for 390 patients attending a catchment-based early intervention service for FEP. Exposure to non-psychotic and subthreshold psychotic symptoms was retrospectively recorded using semi-structured interviews. Outcomes following the onset of the first identifiable symptom were (1) time to onset of FEP and (2) symptom incidence rate (i.e. number of symptoms emerging per person-year until FEP onset). These outcomes were respectively analyzed with Cox proportional hazards and negative binomial regressions.

After Bonferroni correction, having a subthreshold psychotic (v. non-psychotic) symptom as the first symptom was not associated with time to FEP onset [hazard ratio (HR) = 1.39; 95% CI 0.94–2.04] but was associated with higher symptom incidence [incidence rate ratio (IRR) = 1.92; 95% CI 1.10–3.48]. A first symptom of suspiciousness was associated with shorter time to FEP onset (HR = 2.37; 95% CI 1.38–4.08) and higher symptom incidence rate (IRR = 3.20; 95% CI 1.55–7.28) compared to other first symptoms. In contrast, a first symptom of self-harm was associated with lower symptom incidence rate (IRR = 0.06; 95% CI 0.01–0.73) compared to other first symptoms. Several associations between symptoms and illness progression were moderated by the age at symptom onset.

Appreciating the content and timing of early symptoms can identify windows and treatment targets for early interventions in psychosis.

Most research exploring the link between traumatic events and psychotic experiences has focused on either Australia, Europe or North America. In this study, we expand the existing knowledge to Thailand and investigate the impact of the type and the number of traumatic events on psychotic experiences in Thailand.

We used data from the nationally representative 2013 Thai National Mental Health Survey (TNMHS), including questions on traumatic events and psychotic experiences. We regressed the lifetime experience of hallucinations or delusions against the following independent variables: the experience of any traumatic event during lifetime (dichotomous; hypothesis 1); the experience of either no traumatic event, one interpersonal, one unintentional or both interpersonal and unintentional traumatic events (categorical; hypothesis 2) and the number of traumatic events experienced during lifetime (categorical; hypothesis 3). We adjusted the regression models for sociodemographic indicators and psychiatric disorders, and considered survey weights.

About 6% (95% confidence interval: 4.9–7.0) of the respondents stated that they had either hallucinatory or delusional experiences during their lifetime. The risk of reporting such experiences was more than doubled as high among respondents who had experienced at least one traumatic event during their lifetime than among those who had not yet experienced one, with higher risks for interpersonal or multiple traumatic events. Our results further indicated an increase in the risk of psychotic experiences as the number of traumatic events increased, with up to an eight-fold higher risk for people exposed to five or more traumatic events in their lifetime, compared to those with no traumatic events.

Individuals reporting interpersonal or multiple traumatic events face much higher risk of psychotic experiences. Effective and widely accessible secondary prevention programmes for people having experienced interpersonal or multiple traumatic events constitute a key intervention option.

One putative psychological mechanism through which momentary stress impacts on psychosis in individuals with increased liability to the disorder is via affective disturbance. However, to date, this has not been systematically tested. We aimed to investigate whether (i) cross-sectional and temporal effects of momentary stress on psychotic experiences via affective disturbance, and (ii) the reverse pathway of psychotic experiences on stress via affective disturbance were modified by familial liability to psychosis.

The Experience Sampling Method was used in a pooled data set of six studies with three groups of 245 individuals with psychotic disorder, 165 unaffected first-degree relatives, and 244 healthy control individuals to index familial liability. Multilevel moderated mediation models were fitted to investigate indirect effects across groups cross-sectionally and multilevel cross-lagged panel models to investigate temporal effects in the proposed pathways across two measurement occasions.

Evidence on indirect effects from cross-sectional models indicated that, in all three groups, effects of stress on psychotic experiences were mediated by negative affect and, vice versa, effects of psychotic experiences on stress were mediated by negative affect, with all indirect effects being weakest in relatives. Longitudinal modelling of data provided no evidence of temporal priority of stress in exerting its indirect effects on psychotic experiences via affective disturbance or, vice versa.

Our findings tentatively suggest a rapid vicious cycle of stress impacting psychotic experiences via affective disturbances, which does, however, not seem to be consistently modified by familial liability to psychosis.