[Are conspiracy theorists psychotic? A comparison between conspiracy theories and paranoid delusions]. / Zijn complotdenkers psychotisch? Een vergelijking tussen complottheorieën en paranoïde wanen.

BACKGROUND: 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. AIM: To explore the nature, consequences, and social-psychological dimensions of conspiratorial thinking, and describe similarities and differences with paranoid delusions. METHOD: Critically assessing relevant literature about conspiratorial thinking and paranoid delusions. RESULTS: 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. CONCLUSIONS 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.

Development of a stage-dependent prognostic model to predict psychosis in ultra-high-risk patients seeking treatment for co-morbid psychiatric disorders.

BACKGROUND: 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. METHOD: 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. RESULTS: 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. CONCLUSIONS: 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.

Cost-effectiveness of preventing first-episode psychosis in ultra-high-risk subjects: multi-centre randomized controlled trial.

BACKGROUND: 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. METHOD: 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. RESULTS: 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. CONCLUSIONS: 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.

Positive and useful auditory vocal hallucinations: prevalence, characteristics, attributions, and implications for treatment.

OBJECTIVE: Auditory hallucinations that are viewed by patients as positive and useful may be barriers to treatment-seeking. The aim was to assess prevalence, impact, and course of, and attributions to, these voices in psychotic and non-psychotic patients. METHOD: One hundred thirty-one patients of a Voices Clinic and 65 members of the Dutch Resonance Foundation were assessed with the Positive and Useful Voices Inquiry. Data were analyzed using Pearson's chi-square, one-way anova, and Crohnbach's alpha statistics. RESULTS: First voices are most often reported as negative. Positive voices occur more among non-psychotic subjects, but the specific characteristics and diagnosis are not significantly associated. Lifetime prevalence of positive and useful voices ranged between 40% and 60%, with varied prevalence rates over time. Positive voices are experienced by subjects as direct addresses in the third person. Perceived control of voices is significantly associated with the wish to preserve them. Attribution of protective power to positive voices has the strongest association with positive experience. CONCLUSION: Many patients express a desire to preserve these voices. Voice characteristics do not allow for validly discriminating psychotic from non-psychotic disorders.

[The administrative incidence of non-affective psychoses in Friesland and Twente]. / De administratieve incidentie van niet-affectieve psychosen in Friesland en Twente.

BACKGROUND: Research into the risk factors for schizophrenia has once again drawn attention to the geographical differences in the incidence and gender distribution of schizophrenia. The incidence - as recorded by the mental health care services - of non-affective psychotic disorders in the Netherlands is unknown. AIM: To ascertain the mental-health-care recorded incidence of non-affective psychotic disorders in Friesland and Twente in 2002. METHOD: The medical files of all adults who made their first contact with mental health care services in 2002 (n = 6,477) via two clinics in the Netherlands were screened for psychotic symptoms. All patients with psychotic symptoms (n = 242) were included and the clinical diagnosis was recorded. Thirty months later the most recent clinical diagnosis was recorded again. results Within six months of their first contact 75 patients were diagnosed with non-affective disorder. This diagnosis was still valid after 30 months. These results demonstrate an incidence of 2.2/10,000 inhabitants. The male-female ration was 1.8:1. The incidence of psychotic disorder did not differ significantly between the two regions under study. CONCLUSION: The incidence found corresponds to the incidence reported in earlier Dutch studies; it lies on the 75th percentile of the cumulative incidence given in an international review.

[Positive and negative auditory vocal hallucinations]. / Positieve en nuttige auditieve vocale hallucinaties.

BACKGROUND: Modern psychiatry emphasises the negative aspects of hearing voices. However, experience shows that some patients find these voices positive or useful. AIM: To describe the life-time prevalence of hearing voices in a group of patients and the course of this phenomenon and to find out whether these patients find the hearing of voices positive and/or useful. METHOD: The study population consisted of patients and former patients of the Voices Outpatient Department of the Groningen University Medical Centre. For this study the Positive and Useful Voices Inquiry, a self-report questionnaire was developed. RESULTS: The life-time prevalence of positive voices was 52%, whereas the life-time prevalence of useful voices was 40%. In the majority of patients the number of positive voices decreased and the number of useful remained the same. Positive voices provided protection, reassurance or companionship. Useful voices gave advice, assist with daily activities or decision-making. Thirty two percent of the patients wished to continue hearing positive voices, 40% wished to continue hearing useful voices. These wishes were correlated to patients feeling that they have control over these voices. CONCLUSION: The prevalence of positive and useful voices is quite considerable and is therefore therapeutically relevant. A substantial proportion of the patients wishes to continue hearing these types of voices.

Association of treatment delay, migration and urbanicity in psychosis.

BACKGROUND: Several factors may contribute to duration of untreated psychosis (DUP): patient-delay, referral-delay and treatment-delay caused by mental health care services (MHS-delay). In order to find the most effective interventions to reduce DUP, it is important to know what factors in these pathways to care contribute to DUP. AIM: To examine the relationship of the constituents of treatment delay, migration status and urbanicity. METHOD: In first episode psychotic patients (n=182) from rural, urban and highly urbanized areas, DUP, migration status and pathways to care were determined. RESULTS: Mean DUP was 53.6 weeks (median 8.9, SD=116.8). Patient-delay was significantly longer for patients from highly urbanized areas and for first generation immigrants. MHS-delay was longer for patients who were treated already by MHS for other diagnoses. CONCLUSIONS: Specific interventions are needed focusing on patients living in highly urbanized areas and first generation immigrants in order to shorten patient delay. MHS should improve early detection of psychosis in patients already in treatment for other diagnosis.