Functional deficits, that is, problems in fulfilling appropriate social roles in daily life, are very common in people with a psychotic disorder. In recent years, Virtual Reality (VR) has emerged as a potential tool to improve SCT. Our research group has developed an immersive VR-SCT (‘Dynamic Interactive Social Cognition Training in Virtual Reality’: ‘DiSCoVR’).

To evaluate to effects of a VR-based social cognition training (SCT) for people with a psychotic disorder.

This intervention was compared the an active VR-control condition in a multicenter RCT. Both interventions contained sixteen individual 45-60-minute on-site sessions, administered twice a week. Main study outcomes are social cognition and social functioning in daily life assessed with experience sampling.

From baseline to post-treatment (n=72), none of the time*group interactions were significant, indicating an absence of treatment effects. A significant effect of time was observed for the SERS total score (b=9.84, 95% CI=3.81-15.87, p=.002), indicating overall improvement in self-esteem.

We did not find any significant treatment effects. An effect of time on self-esteem was found at post-treatment, but not follow-up, suggesting a temporary improvement in self-esteem in both groups. One way to interpret these results is that, contrary to other SCT interventions, DiSCoVR does not improve social cognition or social functioning. This could be due to characteristics of the treatment protocol. Another possibility is that, contrary to the premise of VR-SCT, our VR environments inadequately simulated reality. Adapting an established protocol to VR, could further elucidate the merit of VR as a training method.

No significant relationships.

Conspiracy theories are popular during the COVID-19 pandemic. Conspiratorial thinking is characterised by the strong conviction that a certain situation that one sees as unjust is the result of a deliberate conspiracy of a group of people with bad intentions. Conspiratorial thinking appears to have many similarities with paranoid delusions.

To explore the nature, consequences, and social-psychological dimensions of conspiratorial thinking, and describe similarities and differences with paranoid delusions.

Critically assessing relevant literature about conspiratorial thinking and paranoid delusions.

Conspiratorial thinking meets epistemic, existential, and social needs. It provides clarity in uncertain times and connection with an in-group of like-minded people. Both conspiratorial thinking and paranoid delusions involve an unjust, persistent, and sometimes bizarre conviction. Unlike conspiracy theorists, people with a paranoid delusion are almost always the only target of the presumed conspiracy, and they usually stand alone in their conviction. Furthermore, conspiracy theories are not based as much on unusual experiences of their inner self, reality, or interpersonal contacts.

Conspirational thinking is common in uncertain circumstances. It gives grip, certainty, moral superiority and social support. Extreme conspirational thinking seems to fit current psychiatric definitions of paranoid delusions, but there are also important differences. To make a distinction with regard to conspiratorial thinking, deepening of conventional definitions of delusions is required. Instead of the strong focus on the erroneous content of delusions, more attention should be given to the underlying idiosyncratic, changed way of experiencing reality.

No significant relationships.

Clinicians in mental healthcare have few objective tools to identify and analyse their patient’s care needs. Clinical decision aids are tools that can support this process.

This study examines whether 1) clinicians working with a clinical decision aid (TREAT) discuss more of their patient’s care needs compared to usual treatment, and 2) agree on more evidence-based treatment decisions.

Clinicians participated in consultations (n=166) with patients diagnosed with psychotic disorders from four Dutch mental healthcare institutions. Primary outcomes were measured with the modified Clinical Decision-making in Routine Care questionnaire and combined with psychiatric, physical and social wellbeing related care needs. A multilevel analysis compared discussed care needs and evidence-based treatment decisions between treatment as usual (TAU) before, TAU after and the TREAT-condition.

First, a significant increase in discussed care needs for TREAT compared to both TAU conditions (b = 20.2, SE = 5.2, p = 0.00 and b = 15.8, SE = 5.4, p = 0.01) was found. Next, a significant increase in evidence-based treatments decisions for care needs was observed for TREAT compared to both TAU conditions (b = 16.7, SE = 4.8, p = 0.00 and b = 16.0, SE = 5.1, p = 0.01).

TREAT improved the discussion about physical health issues and social wellbeing related topics. It also increased evidence-based treatment decisions for care needs which are sometimes overlooked and difficult to treat. Our findings suggest that TREAT makes sense of ROM data and improves guideline-informed care.

No significant relationships.

I am co-founder and have shares of VRelax, a company providing VR relaxation software.

Cognitive deficits may be characteristic for only a subgroup of first-episode psychosis (FEP) and the link with clinical and functional outcomes is less profound than previously thought. This study aimed to identify cognitive subgroups in a large sample of FEP using a clustering approach with healthy controls as a reference group, subsequently linking cognitive subgroups to clinical and functional outcomes.

204 FEP patients were included. Hierarchical cluster analysis was performed using baseline brief assessment of cognition in schizophrenia (BACS). Cognitive subgroups were compared to 40 controls and linked to longitudinal clinical and functional outcomes (PANSS, GAF, self-reported WHODAS 2.0) up to 12-month follow-up.

Three distinct cognitive clusters emerged: relative to controls, we found one cluster with preserved cognition (n = 76), one moderately impaired cluster (n = 74) and one severely impaired cluster (n = 54). Patients with severely impaired cognition had more severe clinical symptoms at baseline, 6- and 12-month follow-up as compared to patients with preserved cognition. General functioning (GAF) in the severely impaired cluster was significantly lower than in those with preserved cognition at baseline and showed trend-level effects at 6- and 12-month follow-up. No significant differences in self-reported functional outcome (WHODAS 2.0) were present.

Current results demonstrate the existence of three distinct cognitive subgroups, corresponding with clinical outcome at baseline, 6- and 12-month follow-up. Importantly, the cognitively preserved subgroup was larger than the severely impaired group. Early identification of discrete cognitive profiles can offer valuable information about the clinical outcome but may not be relevant in predicting self-reported functional outcomes.

Lesbian, bisexual, or gay individuals (LBGs) have an increased risk for mental health problems compared to heterosexuals, but this association has sparsely been investigated for psychotic disorders. The aim of this study was: (1) to examine whether LBG sexual orientation is more prevalent in individuals with a non-affective psychotic disorder (NAPD) than in people without a psychotic disorder; and if so, (2) to explore possible mediating pathways.

Sexual orientation was assessed in the 6-year follow-up assessment of the Dutch Genetic Risk and Outcome of Psychosis study (GROUP), a case–control study with 1547 participants (582 patients with psychotic disorder, 604 siblings, and 361 controls). Binary logistic regression analyses were used to calculate the risk of patients with a psychotic disorder being LBG, compared to siblings and controls. Perceived discrimination, history of bullying, childhood trauma (CT), and sexual identity disclosure were investigated as potential mediating variables.

The proportion of individuals with LBG orientation was 6.8% in patients (n = 40), 4.3% in siblings (n = 26), and 2.5% in controls (n = 10). The age- and gender-adjusted odds ratio of LBG for patients was 1.57 (95% CI 1.08–2.27; p = 0.019), compared to siblings and controls. Discrimination, bullying, and CT all partially mediated this association.

Adverse social experiences related to sexual minority status may increase the risk for NAPD. Sexual identity, behavior, and difficulties need more attention in everyday clinical practice.

Childhood trauma is associated with higher risk for mental disorders, including psychosis. Heightened sensitivity to social stress may be a mechanism. This virtual reality study tested the effect of childhood trauma on level of paranoid ideations and distress in response to social stress, in interaction with psychosis liability and level of social stress exposure.

Seventy-five individuals with higher psychosis liability (55 with recent onset psychotic disorder and 20 at ultra-high risk for psychosis) and 95 individuals with lower psychosis liability (42 siblings and 53 controls) were exposed to a virtual café in five experiments with 0–3 social stressors (crowded, other ethnicity and hostility). Paranoid ideation was measured after each experiment. Subjective distress was self-rated before and after experiments. Multilevel random regression analyses were used to test main effects of childhood trauma and interaction effects.

Childhood trauma was more prevalent in individuals with higher psychosis liability, and was associated with higher level of (subclinical) psychotic and affective symptoms. Individuals with a history of childhood trauma responded with more subjective distress to virtual social stress exposures. The effects of childhood trauma on paranoia and subjective distress were significantly stronger when the number of virtual environmental stressors increased. Higher psychosis liability increased the effect of childhood trauma on peak subjective distress and stress reactivity during experiments.

Childhood trauma is associated with heightened social stress sensitivity and may contribute to psychotic and affective dysregulation later in life, through a sensitized paranoid and stress response to social stressors.

Current ultra-high-risk (UHR) criteria appear insufficient to predict imminent onset of first-episode psychosis, as a meta-analysis showed that about 20% of patients have a psychotic outcome after 2 years. Therefore, we aimed to develop a stage-dependent predictive model in UHR individuals who were seeking help for co-morbid disorders.

Baseline data on symptomatology, and environmental and psychological factors of 185 UHR patients (aged 14–35 years) participating in the Dutch Early Detection and Intervention Evaluation study were analysed with Cox proportional hazard analyses.

At 18 months, the overall transition rate was 17.3%. The final predictor model included five variables: observed blunted affect [hazard ratio (HR) 3.39, 95% confidence interval (CI) 1.56–7.35, p < 0.001], subjective complaints of impaired motor function (HR 5.88, 95% CI 1.21–6.10, p = 0.02), beliefs about social marginalization (HR 2.76, 95% CI 1.14–6.72, p = 0.03), decline in social functioning (HR 1.10, 95% CI 1.01–1.17, p = 0.03), and distress associated with suspiciousness (HR 1.02, 95% CI 1.00–1.03, p = 0.01). The positive predictive value of the model was 80.0%. The resulting prognostic index stratified the general risk into three risk classes with significantly different survival curves. In the highest risk class, transition to psychosis emerged on average ⩾8 months earlier than in the lowest risk class.

Predicting a first-episode psychosis in help-seeking UHR patients was improved using a stage-dependent prognostic model including negative psychotic symptoms (observed flattened affect, subjective impaired motor functioning), impaired social functioning and distress associated with suspiciousness. Treatment intensity may be stratified and personalized using the risk stratification.

Environmental factors such as urban birth and ethnic minority position have been related to risk for psychotic disorders. There is some evidence that not only individual, but also neighborhood characteristics influence this risk. The aim of this study was to investigate social disorganization of neighborhoods and incidence of psychotic disorders.

The research was a 7-year first-contact incidence study of psychotic disorders in The Hague. Neighborhood characteristics included continuous, dichotomous and cumulative measures of socio-economic level, residential mobility, ethnic diversity, proportion of single person households, voter turnout, population density and crime level. Using multilevel Poisson regression analysis, incidence rate ratios (IRRs) and 95% confidence intervals (CIs) of psychotic disorders were calculated for the indicators of neighborhood social disorganization.

A total of 618 incident cases were identified. Neighborhood socio-economic level and residential mobility had the strongest association with incidence of psychotic disorders [individual-level adjusted Wald χ21 = 13.03 (p = 0.0003) and 5.51 (p = 0.02), respectively]. All but one (proportion of single person households) of the dichotomous neighborhood indicators were significantly associated with a higher IRR. The cumulative degree of neighborhood social disorganization was strongly and linearly associated with the incidence of psychotic disorders (trend test, Wald χ25 = 25.76, p = 0.0001). The IRR in neighborhoods with the highest degree of social disorganization was 1.95 (95% CI 1.38–2.75) compared with the lowest disorganization category.

The findings suggest that the risk for developing a psychotic disorder is higher for people living in socially disorganized environments. Longitudinal studies are needed to investigate causality.

Although there is evidence for the effectiveness of interventions for psychosis among ultra-high-risk (UHR) groups, health economic evaluations are lacking. This study aimed to determine the cost effectiveness and cost–utility of cognitive–behavioural therapy (CBT) to prevent first-episode psychosis.

The Dutch Early Detection and Intervention Evaluation study was a randomized controlled trial of 196 UHR patients with an 18-month follow-up. All participants were treated with routine care (RC) for non-psychotic disorders. The experimental group (n = 95) received add-on CBT to prevent first-episode psychosis. We report the intervention, medical and travel costs, as well as costs arising from loss of productivity. Treatment response was defined as psychosis-free survival and quality-adjusted life years (QALYs) gained.

In the cost-effectiveness analysis, the proportion of averted psychoses was significantly higher in the CBT condition (89.5% v. 76.2%). CBT showed a 63.7% probability of being more cost effective, because it was less costly than RC by US$844 (£551) per prevented psychosis. In the cost–utility analysis, QALY health gains were slightly higher for CBT than for RC (0.60 v. 0.57) and the CBT intervention had a 52.3% probability of being the superior treatment because, for equal or better QALY gains, the costs of CBT were lower than those of RC.

Add-on preventive CBT for UHR resulted in a significant reduction in the incidence of first psychosis. QALY gains show little difference between the two conditions. The CBT intervention proved to be cost saving.

The risk for psychotic disorders is increased for many ethnic minority groups and may develop in early childhood. This study investigated whether the prevalence of psychotic experiences (PE) with high impact is higher among ethnic minority youth compared to majority youth and examined the significance of these PE.

A school-based study assessed a large community sample of 1545 ethnic minority and majority children in The Netherlands (mean age 12.98 ± 1.81 years). The Dutch (n = 702, 45.4%), Moroccan-Dutch (n = 400, 25.9%) and Turkish-Dutch (n = 170, 11.0%) ethnic groups could be studied separately. Self-report questionnaires on PE, impact and cultural context were administered.

Prevalence of PE with high impact was 3.1% in Dutch, 9.5% in Moroccan-Dutch and 7.1% in Turkish-Dutch youth. Compared to Dutch youth, odds ratios were 3.0 [95% confidence interval (CI) 1.7–5.1] for Moroccan-Dutch youth and 2.2 (95% CI 1.1–4.6) for Turkish-Dutch youth. Differences were not explained by cultural or religious differences.

The increased risk for psychotic disorders in ethnic minorities may already be detectable in childhood, since PE with high impact were more common among ethnic minority youth compared to majority youth. The additional measurement of impact of PE appears to be a valid approach to identify those children at risk to develop psychotic or other more common psychiatric disorders.

Ethnic minority position is associated with increased risk for psychotic outcomes, which may be mediated by experiences of social exclusion, defeat and discrimination. Sexual minorities are subject to similar stressors. The aim of this study is to examine whether sexual minorities are at increased risk for psychotic symptoms and to explore mediating pathways.

A cross-sectional survey was performed assessing cumulative incidence of psychotic symptoms with the Composite International Diagnostic Interview in two separate random general population samples (NEMESIS-1 and NEMESIS-2). Participants were sexually active and aged 18–64 years (n = 5927, n = 5308). Being lesbian, gay or bisexual (LGB) was defined as having sexual relations with at least one same-sex partner during the past year. Lifetime experience of any psychotic symptom was analysed using logistic regression, adjusted for gender, educational level, urbanicity, foreign-born parents, living without a partner, cannabis use and other drug use.

The rate of any psychotic symptom was elevated in the LGB population as compared with the heterosexual population both in NEMESIS-1 [odds ratio (OR) 2.56, 95% confidence interval (CI) 1.71–3.84] and NEMESIS-2 (OR 2.30, 95% CI 1.42–3.71). Childhood trauma, bullying and experience of discrimination partly mediated the association.

The finding that LGB orientation is associated with psychotic symptoms adds to the growing body of literature linking minority status with psychosis and other mental health problems, and suggests that exposure to minority stress represents an important mechanism.

Ethnicity has been associated with different incidence rates and different symptom profiles in young patients with psychotic-like disorders. No studies so far have examined the effect of ethnicity on symptoms in people with an At Risk Mental State (ARMS).

In this cross-sectional study, we analysed the relationship between ethnicity and baseline data on the severity of psychopathology scores in 201 help-seeking patients who met the ARMS criteria and agreed to participate in the Dutch Early Detection and Intervention (EDIE-NL) trial. Eighty-seven of these patients had a non-Dutch ethnicity. We explored the possible mediating role of ethnic identity.

Higher rates of negative symptoms, and of anhedonia in particular, were found in the ethnic minority group. This result could be attributed mainly to the Moroccan-Dutch and Turkish-Dutch subgroups, who also presented with more depression symptoms when the groups were examined separately. The ethnic minority group displayed a lower level of ethnic group identity compared to the immigrants of the International Comparative Study of Ethnocultural Youth (ICSEY). Ethnic identity was inversely related to symptoms in the Moroccan-Dutch patient group.

The prevalence of more severe negative symptoms and depression symptoms in ethnic minority groups deserves more attention, as the experience of attenuated positive symptoms when accompanied by negative symptoms or distress has proven to be predictive for transition to a first psychotic episode.

Cannabis use may be a risk factor for schizophrenia. Part of this association may be explained by genotype–environment interaction, and part of it by genotype–environment correlation. The latter issue has not been explored. We investigated whether cannabis use is associated with schizophrenia, and whether gene–environment correlation contributes to this association, by examining the prevalence of cannabis use in groups with different levels of genetic predisposition for schizophrenia.

Case-control study of first-episode schizophrenia. Cases included all non-Western immigrants who made first contact with a physician for schizophrenia in The Hague, The Netherlands, between October 2000 and July 2005 (n=100; highest genetic predisposition). Two matched control groups were recruited, one among siblings of the cases (n=63; intermediate genetic predisposition) and one among immigrants who made contact with non-psychiatric secondary health-care services (n=100; lowest genetic predisposition). Conditional logistic regression analyses were used to predict schizophrenia as a function of cannabis use, and cannabis use as a function of genetic predisposition for schizophrenia.

Cases had used cannabis significantly more often than their siblings and general hospital controls (59, 21 and 21% respectively). Cannabis use predicted schizophrenia [adjusted odds ratio (OR) cases compared to general hospital controls 7.8, 95% confidence interval (CI) 2.7–22.6; adjusted OR cases compared to siblings 15.9 (95% CI 1.5–167.1)], but genetic predisposition for schizophrenia did not predict cannabis use [adjusted OR intermediate predisposition compared to lowest predisposition 1.2 (95% CI 0.4–3.8)].

Cannabis use was associated with schizophrenia but there was no evidence for genotype–environment correlation.