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Impaired metacognition is associated with difficulties in the daily functioning of people with psychosis. Metacognition can be divided into four domains: Self-Reflection, Understanding the Other's Mind, Decentration, and Mastery. This study investigated whether Metacognitive Reflection and Insight Therapy (MERIT) can be used to improve metacognition.
This study is a randomized controlled trial. Patients in the active condition (n = 35) received forty MERIT sessions, the control group (n = 35) received treatment as usual. Multilevel intention-to-treat and completers analyses were performed for metacognition and secondary outcomes (psychotic symptomatology, cognitive insight, Theory of Mind, empathy, depression, self-stigma, quality of life, social functioning, and work readiness).
Eighteen out of 35 participants finished treatment, half the drop-out stemmed from therapist attrition (N = 5) or before the first session (N = 4). Intention-to-treat analysis demonstrated that in both groups metacognition improved between pre- and post-measurements, with no significant differences between the groups. Patients who received MERIT continued to improve, while the control group returned to baseline, leading to significant differences at follow-up. Completers analysis (18/35) showed improvements on the Metacognition Assessment Scale (MAS-A) scales Self Reflectivity and metacognitive Mastery at follow-up. No effects were found on secondary outcomes.
On average, participants in the MERIT group were, based on MAS-A scores, at follow-up more likely to recognize their thoughts as changeable rather than as facts. MERIT might be useful for patients whose self-reflection is too limited to benefit from other therapies. Given how no changes were found in secondary measures, further research is needed. Limitations and suggestions for future research are discussed.
We present 12-month follow-up results for a randomised controlled trial of prolonged exposure and eye movement desensitisation and reprocessing (EMDR) therapy in 85 (78.8%) participants with psychotic disorder and comorbid post-traumatic stress disorder (PTSD). Positive effects on clinician-rated PTSD, self-rated PTSD, depression, paranoid-referential thinking and remission from schizophrenia were maintained up to 12-month follow-up. Negative post-traumatic cognitions declined in prolonged exposure and were stable in EMDR. A significant decline in social functioning was found, whereas reductions in interference of PTSD symptoms with social functioning were maintained. These results support that current PTSD guidelines apply to individuals with psychosis.
Declaration of interest
M.v.d.G. and D.v.d.B. receive income for published books on psychotic disorders and for the training of postdoctoral professionals in the treatment of psychotic disorders. A.d.J. receives income for published books on EMDR therapy and for the training of postdoctoral professionals in this method. A.v.M. receives income for published book chapters on PTSD and for the training of postdoctoral professionals in prolonged exposure. C.d.R. receives income for the training of postdoctoral professionals in EMDR therapy.
This study presents secondary analyses of a recently published trial in which post-traumatic stress disorder (PTSD) patients with psychosis (n = 108) underwent 8 sessions of trauma-focused treatment, either prolonged exposure (PE) or eye movement desensitisation and reprocessing (EMDR) therapy. 24.1% fulfilled the criteria for the dissociative subtype, a newly introduced PTSD subtype in DSM-5. Treatment outcome was compared for patients with and without the dissociative subtype of PTSD. Patients with the dissociative subtype of PTSD showed large reductions in clinician-administered PTSD scale (CAPS) score, comparable with patients without the dissociative subtype of PTSD. It is concluded that even in a population with severe mental illness, patients with the dissociative subtype of PTSD do benefit from trauma-focused treatments without a pre-phase of emotion regulation skill training and should not be excluded from these treatments.
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.
In patients with psychotic disorders, the effects of psychological post-traumatic stress disorder (PTSD) treatment on symptoms of psychosis, depression and social functioning are largely unknown
In a single-blind randomized controlled trial (RCT) 155 outpatients in treatment for psychosis (61.3% schizophrenic disorder, 29% schizoaffective disorder) were randomized to eight sessions prolonged exposure (PE; n = 53) or eye movement desensitization and reprocessing (EMDR) (n = 55), or a waiting-list condition (WL, n = 47) for treatment of their co-morbid PTSD. Measures were performed on (1) psychosis: severity of delusions (PSYRATS-DRS), paranoid thoughts (GPTS), auditory verbal hallucinations (PSYRATS-AHRS), and remission from psychotic disorder (SCI-SR-PANSS); (2) depression (BDI-II); (3) social functioning (PSP). Outcomes were compared at baseline, post-treatment, 6-month follow-up and over all data points.
Both PE and EMDR were significantly associated with less severe paranoid thoughts post-treatment and at 6-month follow-up, and with more patients remitting from schizophrenia, at post-treatment (PE and EMDR) and over time (PE). Moreover, PE was significantly associated with a greater reduction of depression at post-treatment and at 6-month follow-up. Auditory verbal hallucinations and social functioning remained unchanged.
In patients with chronic psychotic disorders PE and EMDR not only reduced PTSD symptoms, but also paranoid thoughts. Importantly, in PE and EMDR more patients accomplished the status of their psychotic disorder in remission. Clinically, these effects are highly relevant and provide empirical support to the notion that delivering PTSD treatment to patients with psychotic disorders and PTSD deserves increasing recognition and acceptance among clinicians.
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.
Previous research has established the relationship between cannabis use and psychotic disorders. Whether cannabis use is related to transition to psychosis in patients at ultra-high risk (UHR) for psychosis remains unclear. The present study aimed to review the existing evidence on the association between cannabis use and transition to psychosis in UHR samples.
A search of PsychInfo, Embase and Medline was conducted from 1996 to August 2015. The search yielded 5559 potentially relevant articles that were selected on title and abstract. Subsequently 36 articles were screened on full text for eligibility. Two random-effects meta-analyses were performed. First, we compared transition rates to psychosis of UHR individuals with lifetime cannabis use with non-cannabis-using UHR individuals. Second, we compared transition rates of UHR individuals with a current DSM-IV cannabis abuse or dependence diagnosis with lifetime users and non-using UHR individuals.
We found seven prospective studies reporting on lifetime cannabis use in UHR subjects (n = 1171). Of these studies, five also examined current cannabis abuse or dependence. Lifetime cannabis use was not significantly associated with transition to psychosis [odds ratio (OR) 1.14, 95% confidence interval (CI) 0.856–1.524, p = 0.37]. A second meta-analysis yielded an OR of 1.75 (95% CI 1.135–2.710, p = 0.01), indicating a significant association between current cannabis abuse or dependence and transition to psychosis.
Our results show that cannabis use was only predictive of transition to psychosis in those who met criteria for cannabis abuse or dependence, tentatively suggesting a dose–response relationship between current cannabis use and transition to psychosis.
Metacognitive training (MCT) for schizophrenia spectrum is widely implemented. It is timely to systematically review the literature and to conduct a meta-analysis.
Eligible studies were selected from several sources (databases and expert suggestions). Criteria included comparative studies with a MCT condition measuring positive symptoms and/or delusions and/or data-gathering bias. Three meta-analyses were conducted on data gathering (three studies; 219 participants), delusions (seven studies; 500 participants) and positive symptoms (nine studies; 436 participants). Hedges’ g is reported as the effect size of interest. Statistical power was sufficient to detect small to moderate effects.
All analyses yielded small non-significant effect sizes (0.26 for positive symptoms; 0.22 for delusions; 0.31 for data-gathering bias). Corrections for publication bias further reduced the effect sizes to 0.21 for positive symptoms and to 0.03 for delusions. In blinded studies, the corrected effect sizes were 0.22 for positive symptoms and 0.03 for delusions. In studies using proper intention-to-treat statistics the effect sizes were 0.10 for positive symptoms and −0.02 for delusions. The moderate to high heterogeneity in most analyses suggests that processes other than MCT alone have an impact on the results.
The studies so far do not support a positive effect for MCT on positive symptoms, delusions and data gathering. The methodology of most studies was poor and sensitivity analyses to control for methodological flaws reduced the effect sizes considerably. More rigorous research would be helpful in order to create enough statistical power to detect small effect sizes and to reduce heterogeneity. Limitations and strengths are discussed.
Post-traumatic stress disorder (PTSD) is highly prevalent in patients with a psychotic disorder. Because a PTSD diagnosis is often missed in patients with psychosis in routine care, a valid screening instrument could be helpful.
To determine the validity of the Trauma Screening Questionnaire (TSQ) as a screening tool for PTSD among individuals with psychotic disorders.
Among 2608 patients with a psychotic disorder, the rate of trauma exposure was determined and the TSQ was administered to screen for PTSD. PTSD status was verified in 455 patients using the Clinician-Administered PTSD Scale (trial registration: ISRCTN 79584912).
Trauma exposure was reported by 78.2% of the 2608 patients. PTSD prevalence was estimated at 16% (95% CI 14.6–17.4%) compared with 0.5% reported in the patients' clinical charts. A TSQ cut-off score of six predicted PTSD with 78.8% sensitivity, 75.6% specificity, 44.5% correct positives and 93.6% correct negatives.
The TSQ seems to be a valid screening tool for PTSD in patients with a psychotic disorder.
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.
There is an increasing interest in cognitive–behavioural therapy (CBT) interventions targeting negative symptoms in schizophrenia. To date, CBT trials primarily focused on positive symptoms and investigated change in negative symptoms only as a secondary outcome. To enhance insight into factors contributing to improvement of negative symptoms, and to identify subgroups of patients that may benefit most from CBT directed at ameliorating negative symptoms, we reviewed all available evidence on these outcomes.
A systematic search of the literature was conducted in PsychInfo, PubMed and the Cochrane register to identify randomized controlled trials reporting on the impact of CBT interventions on negative symptoms in schizophrenia. Random-effects meta-analyses were performed on end-of-treatment, short-term and long-term changes in negative symptoms.
A total of 35 publications covering 30 trials in 2312 patients, published between 1993 and 2013, were included. Our results showed studies’ pooled effect on symptom alleviation to be small [Hedges’ g = 0.093, 95% confidence interval (CI) −0.028 to 0.214, p = 0.130] and heterogeneous (Q = 73.067, degrees of freedom = 29, p < 0.001, τ2 = 0.081, I2 = 60.31) in studies with negative symptoms as a secondary outcome. Similar results were found for studies focused on negative symptom reduction (Hedges’ g = 0.157, 95% CI −0.10 to 0.409, p = 0.225). Meta-regression revealed that stronger treatment effects were associated with earlier year of publication, lower study quality and with CBT provided individually (as compared with group-based).
The co-occurring beneficial effect of conventional CBT on negative symptoms found in older studies was not supported by more recent studies. It is now necessary to further disentangle effective treatment ingredients of older studies in order to guide the development of future CBT interventions aimed at negative symptom reduction.
Metacognitive training (MCT) for patients with psychosis is a psychological group intervention that aims to educate patients about common cognitive biases underlying delusion formation and maintenance, and to highlight their negative consequences in daily functioning.
In this randomized controlled trial, 154 schizophrenia spectrum patients with delusions were randomly assigned to either MCT + treatment as usual (TAU) or TAU alone. Both groups were assessed at baseline, and again after 8 and 24 weeks. The trial was completed fully by 111 patients. Efficacy was measured with the Psychotic Symptom Rating Scales (PSYRATS) Delusions Rating Scale (DRS), and with specific secondary measures referring to persecutory ideas and ideas of social reference (the Green Paranoid Thoughts Scale, GPTS), cognitive insight (the Beck Cognitive Insight Scale, BCIS), subjective experiences of cognitive biases (the Davos Assessment of Cognitive Biases Scale, DACOBS) and metacognitive beliefs (the 30-item Metacognitions Questionnaire, MCQ-30). Economic analysis focused on the balance between societal costs and health outcomes (quality-adjusted life years, QALYs).
Both conditions showed a decrease of delusions. MCT was not more efficacious in terms of reducing delusions, nor did it change subjective paranoid thinking and ideas of social reference, cognitive insight or subjective experience of cognitive biases and metacognitive beliefs. The results of the economic analysis were not in favour of MCT + TAU.
In the present study, MCT did not affect delusion scores and self-reported cognitive insight, or subjective experience of cognitive biases and metacognitive beliefs. MCT was not cost-effective.
Depression is a clinically relevant dimension, associated with both positive and negative symptoms, in patients with schizophrenia. However, in siblings it is unknown whether depression is associated with subclinical positive and negative symptoms.
Depressive symptoms and their association with positive and negative symptoms were examined in 813 healthy siblings of patients with a non-affective psychotic disorder, 822 patients and 527 healthy controls. Depressive episodes meeting DSM-IV-TR criteria (lifetime) and depressed mood (lifetime) were assessed with the Comprehensive Assessment of Symptoms and History (CASH) in all three groups. In the patient group, the severity of positive and negative psychosis symptoms was assessed with the CASH. In the siblings and healthy controls, the severity of subclinical psychosis symptoms was assessed with the Community Assessment of Psychic Experiences (CAPE).
Patients reported more lifetime depressed mood and more depressive episodes than both siblings and controls. Siblings had a higher chance of meeting lifetime depressive episodes than the controls; no significant differences in depressed mood were found between siblings and controls. In all three groups the number and duration of depressive symptoms were associated with (sub)clinical negative symptoms. In the patients and siblings the number of depressive symptoms was furthermore associated with (sub)clinical positive symptoms. Finally, lifetime depressed mood showed familial clustering but this clustering was absent for lifetime depressive episodes.
These findings suggest that a co-occurring genetic vulnerability for both depressive and psychotic symptomatology exists on a clinical and a subclinical level.
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.
Low energy ion damage effects have been investigated in GaAs-A1GaAs two dimensional electron gas (2DEG) materials. The effect of ion mass (He, Ar, Xe) and adsorbed C12 on the charge carrier density and mobility has been studied for ion bombarded 2DEG systems. The 2DEG mobility was significantly reduced by ion damage with the effect becoming more dramatic with smaller ion mass. For the same treatment, the two dimensional carrier density was relatively unaffected. The results of He ion exposure showed serious degradation of the 2DEG with moderate ion dose. Electrical measurements were performed to determine the conducting widths of narrow patterned wires. For the same structural widths (mask width) He defined wires showed smaller electrical widths than Ar milling in the presence of chlorine. Serious limitations to patterning small structures may be imposed using beam processes that include He or other light mass species.
We describe here an effort to provide lateral confinement of carriers within a continuous InGaAs quantum well by creating a pattern of strain in the well. A compressed InGaAsP layer overlying the quantum well and the InP barrier was patterned into submicron stressor wires by etching to within approximately 20 nm of the InP barrier. The relaxation of the compression at the edges of the quaternary stressors resulted in dilation of the quantum well material under their centers, thus lowering the band gap of the material, providing confinement for both electrons and holes there. We observed a red shift of the quantum well luminescence of 7 meV for 400 nm wide wires, evidence for the strain-induced lateral confinement. This is the first observation of a red-shifted band gap in submicron strain-confining structures.
We have studied excitation transfer from the host quantum well to strain-confined quantum dots. We find that there is a long-lived intermediate state acting as a reservoir, holding the excitation before it is thermally activated over a barrier to reach the quantum dot. The barrier height increases monotonically with dot size.
Interventions to improve adherence to treatment in people with psychotic disorders have produced inconclusive results. We developed a new treatment, treatment adherence therapy (TAT), whose intervention modules are tailored to the reasons for an individual's non-adherence.
To examine the effectiveness of TAT with regard to service engagement and medication adherence in out-patients with psychotic disorders who engage poorly.
Randomised controlled study of TAT v. treatment as usual (TAU) in 109 out-patients. Most outcome measurements were performed by masked assessors. We used intention-to-treat multivariate analyses (Dutch Trial Registry: NTR1159).
Treatment adherence therapy v. TAU significantly benefited service engagement (Cohen's d = 0.48) and medication adherence (Cohen's d = 0.43). Results remained significant at 6-month follow-up for medication adherence. Near-significant effects were also found regarding involuntary readmissions (1.9% v. 11.8%, P = 0.053). Symptoms and quality of life did not improve.
Treatment adherence therapy helps improve engagement and adherence, and may prevent involuntary admission.