[Ecological momentary assessment as a clinical tool in psychiatry: promises, pitfalls, and possibilities]. / Dagboekmetingen als hulpmiddel in de psychiatrische zorg: beloften, valkuilen en mogelijkheden.

BACKGROUND: Ecological momentary assessment (EMA) is a promising method to gain insight into the daily lives of people with mental disorders. EMA can be used to monitor mood, symptoms, and experiences multiple times per day. Using advanced statistical methods, such as network analysis, as EMA feedback might result in novel insights that are relevant to psychiatric care. AIM: To investigate the promise, pitfalls, and possibilities of EMA and network analysis for psychiatric care. METHOD: Empirical network studies, reviews, and qualitative research were employed to investigate the state of research and the perspectives of patients and clinicians on EMA and network analysis. Furthermore, an empirical study will be discussed, in which twenty patients with bipolar disorders completed five EMA diaries per day for four months within treatment. RESULTS: Studies using network analysis demonstrated conflicting results. Qualitative research indicated that bipolar patients and clinicians are aware of the added benefit of EMA for psychiatric care, especially for improving insight and self-management. At the same time, EMA was seen as burdensome. Personalization and integration with existing treatment protocols emerged as necessary requirements for adequate implementation of EMA in psychiatric care. CONCLUSION: EMA can have added value for psychiatric care, provided it is adequately implemented. BACKGROUND: Ecological momentary assessment (EMA) is a promising method to gain insight into the daily lives of people with mental disorders. EMA can be used to monitor mood, symptoms, and experiences multiple times per day. Using advanced statistical methods, such as network analysis, as EMA feedback might result in novel insights that are relevant to psychiatric care. AIM: To investigate the promise, pitfalls, and possibilities of EMA and network analysis for psychiatric care. METHOD: Empirical network studies, reviews, and qualitative research were employed to investigate the state of research and the perspectives of patients and clinicians on EMA and network analysis. Furthermore, an empirical study will be discussed, in which twenty patients with bipolar disorders completed five EMA diaries per day for four months within treatment. RESULTS: Studies using network analysis demonstrated conflicting results. Qualitative research indicated that bipolar patients and clinicians are aware of the added benefit of EMA for psychiatric care, especially for improving insight and self-management. At the same time, EMA was seen as burdensome. Personalization and integration with existing treatment protocols emerged as necessary requirements for adequate implementation of EMA in psychiatric care. CONCLUSION: EMA can have added value for psychiatric care, provided it is adequately implemented.

[Use of the Triangle of Care Card and its influence on the cooperation with caregivers and clients]. / Gebruik van Triadekaart en invloed op de samenwerking met naastbetrokkenen.

BACKGROUND: Although there is consensus on the importance of involving informal caregivers of people with severe mental illness, interventions are needed to support this. AIM: To explore whether the use of the 'Triangle of Care Card', an instrument developed to help strengthen the role of care-givers in their contact with workers, increases quality of cooperation and care. METHOD: Three outpatient mental health teams and twelve teams for supported housing started working with the card. Information from files and questionnaires were used to monitor change and compare this with the changes during the same year in ten other teams. RESULTS: Use of the Triangle of Care Card was sparse. When it was used, a broader range of subjects were discussed, including the needs of caregivers. Also, clients were more involved. In teams where the card was introduced, the clients' networks became more apparent and there was an increase in face-to-face meetings with members of this network. CONCLUSION: Introduction of the Triangle of Care Card leads to change in the involvement of caregivers. However, implementation is problematic and therefore the increase in quality of the cooperation with caregivers and quality of care is yet small.

[An antipsychotic without dopamine receptor blockade?] / Een antipsychoticum zonder dopamine­receptorblokkade?

BACKGROUND: Current antipsychotic treatment is suboptimal. There is an urgent need for new antipsychotics with new mechanisms of action. SEP-363856 is a trace amine-associated receptor 1 (TAAR1) agonist and a serotonin 5-HT1a agonist with potential antipsychotic properties. AIM: To describe the rationale for the development of SEP-363856, the pharmacology of TAAR1/5-HT1a agonists, and the clinical efficacy of SEP-363856. METHOD: A narrative review of the literature using PubMed, Embase and PsychINFO. RESULTS: Six publications were identified, one of which was a phase 2 clinical trial with SEP-363856. This phase 2 study shows that SEP-363856 is an effective and well-tolerated antipsychotic; positive, but also negative symptoms decreased; motor side effects (akathisia) and prolactin increase did not occur, while metabolic side effects hardly occurred. Reported side-effects were somnolence and nausea. The antipsychotic activity of SEP-363856 appears to be (pre)clinical not based on D2 antagonism, but on TAAR1 and 5-HT1a agonism. CONCLUSION: TAAR1 and 5-HT1a agonists such as SEP-363856 may be a treatment option for psychosis. Hopefully they can be further developed into an antipsychotic with a favorable effectiveness and tolerability profile.

Vitamin D concentration and psychotic disorder: associations with disease status, clinical variables and urbanicity.

BACKGROUND: The association between schizophrenia and decreased vitamin D levels is well documented. Low maternal and postnatal vitamin D levels suggest a possible etiological mechanism. Alternatively, vitamin D deficiency in patients with schizophrenia is presumably (also) the result of disease-related factors or demographic risk factors such as urbanicity. METHODS: In a study population of 347 patients with psychotic disorder and 282 controls, group differences in vitamin D concentration were examined. Within the patient group, associations between vitamin D, symptom levels and clinical variables were analyzed. Group × urbanicity interactions in the model of vitamin D concentration were examined. Both current urbanicity and urbanicity at birth were assessed. RESULTS: Vitamin D concentrations were significantly lower in patients (B = -8.05; 95% confidence interval (CI) -13.68 to -2.42; p = 0.005). In patients, higher vitamin D concentration was associated with lower positive (B = -0.02; 95% CI -0.04 to 0.00; p = 0.049) and negative symptom levels (B = -0.03; 95% CI -0.05 to -0.01; p = 0.008). Group differences were moderated by urbanicity at birth (χ2 = 6.76 and p = 0.001), but not by current urbanicity (χ2 = 1.50 and p = 0.224). Urbanicity at birth was negatively associated with vitamin D concentration in patients (B = -5.11; 95% CI -9.41 to -0.81; p = 0.020), but not in controls (B = 0.72; 95% CI -4.02 to 5.46; p = 0.765). CONCLUSIONS: Lower vitamin D levels in patients with psychotic disorder may in part reflect the effect of psychosis risk mediated by early environmental adversity. The data also suggest that lower vitamin D and psychopathology may be related through direct or indirect mechanisms.

[Decision aid for the treatment of psychotic illness: development of TReatment E-AssisT (TREAT)]. / Beslistool bij de behandeling van psycho-tische aandoeningen: de ontwikkeling van TReatment E-AssisT (TREAT).

BACKGROUND: Use of decision aids in mental health care is increasing and will also be introduced in the Dutch mental healthcare system. We describe the context of this development and discuss how decision aids could facilitate evidence-based psychiatry.
AIM: To describe the development of the decision aid TReatment E-Assist (TREAT) in the Dutch mental healthcare system that aims to optimize treatment of people with a psychotic illness.
METHOD: We describe how the TREAT application works and discuss its potential contribution to the treatment of people with a psychotic illness.
RESULTS: In a pilot study TREAT was judged as user friendly and useful. TREAT seemed to increase the integration of ROM-results in treatment and the advice offered new view points for practioners.
CONCLUSION: TREAT is a novel application which combines routine outcome monitoring results with current treatment guidelines and standards of care in order to generate personalised treatment recommendations in the context of a psychiatric treatment trajectory. A multicentre study is being conducted in different provinces in the Netherlands to investigate the effectiveness of TREAT.

Long-term cognitive trajectories and heterogeneity in patients with schizophrenia and their unaffected siblings.

OBJECTIVE: This study aimed to assess the heterogeneity and stability of cognition in patients with a non-affective psychotic disorder and their unaffected siblings. In addition, we aimed to predict the cognitive subtypes of siblings by their probands. METHOD: Assessments were conducted at baseline, 3 and 6 years in 1119 patients, 1059 siblings and 586 controls from the Genetic Risk and Outcome of Psychosis (GROUP) study. Group-based trajectory modeling was applied to identify trajectories and clustered multinomial logistic regression analysis was used for prediction modeling. A composite score of eight neurocognitive tests was used to measure cognitive performance. RESULTS: Five stable cognitive trajectories ranging from severely altered to high cognitive performance were identified in patients. Likewise, four stable trajectories ranging from moderately altered to high performance were found in siblings. Siblings had a higher risk of cognitive alteration when patients' alteration was mild (OR = 2.21), moderate (OR = 5.70), and severe (OR = 10.07) compared with patients with intact cognitive function. The familial correlation coefficient between pairs of index patients and their siblings was 0.27 (P = 0.003). CONCLUSIONS: The cognitive profiles identified in the current study might be suitable as endophenotypes and could be used in future genetic studies and predicting functional and clinical outcomes.

[Personalised medicine for psychosis]. / Personalised medicine bij psychotische stoornissen.

BACKGROUND: Personalised medicine (pm) means treatment that specifically targets the needs of individual patients on the basis of genetic, biomarker, phenotypic or psychosocial characteristics.
AIM: To update our knowledge about the current use of pm in the treatment of psychotic disorders.
METHOD: Review of the literature on pm for psychoses.
RESULTS: At the moment, genetic and other biological characteristics cannot be used for the diagnosis and treatment of psychotic disorders because they are not sensitive enough and their specificity is too low. We investigated immunulogical, oxidative, metabolic, hormonal and dopaminergic aspects that could lead to the use of pm. pm is already being used on the basis of phenotypical, cognitive and psychosocial characteristics; those characteristics include substance abuse, cognitive dysfunction, ethnicity and childhood trauma.
CONCLUSION: In the next years there may be more opportunities for using for pm in psychosis. The increase may results from large genetic network studies and treatment studies involving stratification based on hypothetical specific mechanisms instead of on the categorical diagnosis of illnesses such as schizophrenia.

Course of auditory vocal hallucinations in childhood: 11-year follow-up study.

OBJECTIVE: Childhood auditory vocal hallucinations (AVH) are mostly transient but may predict clinical outcomes. Little is known about their course over time and associations with risk factors, and how this may inform early intervention. Our objective was to assess the 11-year course of AVH, associated psychopathology and risk factors. METHOD: A 5-year (T1) and 11-year (T2) follow-up of a baseline case-control sample (n = 694, of whom 347 with AVH). At T2, online assessment of AVH, other psychotic experiences, psychopathology, trauma and cannabis use was completed by 293 adolescents aged 18-19 years. RESULTS: The AVH 6-year (T1-T2) persistence rate was 18.2%, and the AVH 11-year (T0-T2) persistence rate was 6.2%. AVH at T2 were associated with higher levels of T2 other psychotic experiences, T2 psychopathology and T2 traumatic events, but not with T2 stress or T2 cannabis use. Persistence of AVH (i.e. AVH reported two or three times from T0) was associated with T2 traumatic events and higher risk for post-traumatic stress disorder. CONCLUSION: Auditory vocal hallucinations in early childhood are mostly transitory. AVH in adolescence, especially when persistent, are associated with affective symptoms and environmental risk, particularly traumatic events.

[A study of cost-effectiveness of treating serious mental illness: challenges and solutions]. / Doelmatigheidsonderzoek bij mensen met een ernstige psychische aandoening: uitdagingen en oplossingen.

BACKGROUND People with serious mental illness (SMI) often suffer high healthcare costs and enduring loss of quality of life. Increasing our understanding of the cost-effectiveness of people with SMI is important when striving for optimal health at affordable costs. AIM To describe aspects that can be important for cost-effectiveness research targeting people with SMI. METHOD These aspects are demonstrated by considering pro-active care, rehabilitation and involuntary treatment RESULTS The possible involvement of a large number of stakeholders outside of healthcare requires cost-effectiveness research to also map the costs and benefits outside of healthcare, preferably for each stakeholder specifically. Availability of data, the possibility to combine datasets, and ways to deal with dropouts require extra attention. CONCLUSION Cost-effectiveness research targeting people with SMI could be enhanced when solutions are found for the availability of data inside and outside of healthcare and when dropout can be compensated for by other sources of data, such that costs and benefits for each stakeholder can be estimated more reliably.

Childhood abuse and neglect in relation to the presence and persistence of psychotic and depressive symptomatology.

BACKGROUND: The association between childhood trauma and psychotic and depressive symptomatology is well established. However, less is known about the specificity and course of these symptoms in relation to childhood trauma. METHOD: In a large sample (n = 2765) of patients with psychosis (n = 1119), their siblings (n = 1057) and controls (n = 589), multivariate (mixed-effects) regression analyses with multiple outcomes were performed to examine the association between childhood trauma and psychotic and depressive symptomatology over a 3-year period. RESULTS: A dose-response relationship was found between childhood trauma and psychosis. Abuse was more strongly associated with positive symptoms than with negative symptoms whereas the strength of the associations between neglect and positive and negative symptoms was comparable. In patients, similar associations between childhood trauma and psychotic or depressive symptoms were found, and in siblings and controls, stronger associations were found between trauma and depressive symptomatology. Childhood trauma was not related to a differential course of symptoms over a 3-year time period. CONCLUSIONS: In congruence with earlier work, our findings suggest that childhood trauma, and abuse in particular, is associated with (subthreshold) psychosis. However, childhood trauma does not seem to be associated with a differential course of symptoms, nor does it uniquely heighten the chance of developing (subthreshold) psychotic symptomatology. Our results indicate that trauma may instead contribute to a shared vulnerability for psychotic and depressive symptoms.

[Cost-effectiveness in Dutch mental health care: future because of ROM?]. / Doelmatigheid in de ggz: toekomst dankzij ROM?

BACKGROUND: The document reporting Dutch mental health care negotiations for 2014-2017 calls for a cost decrease based on cost-effectiveness. Thanks to ROM, the Dutch mental health care seems well prepared for cost-effectiveness research. AIM: Evaluate how valid cost-effectiveness research should be established in mental health care and the role of rom therein. METHOD: Evaluation of requirements of cost-effectiveness research, trends, and a translation to Dutch mental health care. RESULTS: Valid cost-effectiveness research in mental health care requires the application of a societal perspective, a long time-horizon and an adequate evaluation of quality of life of patients. Healthcare consumption, outcome of care and characterisation of the patient population should be measured systematically and continuously. Currently, rom-data are not suitable to serve as a basis for cost-effectiveness research, although a proper basis is present. Further development of rom could lead to a situation in which mental health care is purchased on the basis of cost-effectiveness. However, cost-effectiveness will only really be improved if quality of care is rewarded, rather than rewarding activities that are not always related to outcome of care. CONCLUSION: Cost-effectiveness research in mental health care should focus on societal costs and benefits, quality of life and a long time-horizon. If developed further, rom has the potential to be a basis for cost-effectiveness research in the future.

[Functional remission of people with serious mental illness (SMI): psychometric properties of a new ROM-instrument]. / Functionele remissie bij mensen met een ernstige psychiatrische aandoening; psychometrische eigenschappen van een nieuw ROM-instrument.

BACKGROUND: Instruments are used for routine outcome monitoring of patients with severe mental illness in order to measure psychiatric symptoms, care needs and quality of life. By adding an instrument for measuring functional remission a more complete picture can be given of the complaints, the symptoms and general functioning, which can give direction to providing care for patients with severe mental illness. AIM: To describe the development and testing of a new instrument of functional remission (FR) among people with a psychotic disorder or another serious mental disorder (SMI) as an addition to the symptomatic remission (SR), according to international criteria. METHOD: The FR-assessment involves assessment by a mental health professional who conducts a semi-structured interview with the patient and his or her family and/or uses patient files relating to the three areas of functioning: daily living and self-care; work, study and housekeeping; and social contacts. These areas are rated on a three-point scale of 0: independent; 1: partially independent; 2: dependent. The assessment covers a period of six months, in accordance with the measurement of symptomatic remission and should be part of regular routine outcome monitoring (ROM) procedures. The FR-instrument was used in 2012 with 840 patients from eight Dutch mental care institutions and included a one-year follow-up among 523 patients (response 62%). RESULTS: The results showed that the instrument is relatively easily to complete. It was also relevant for clinical practice, although further research is needed because of the raters' low response. Intra- and inter-rater reliability, discriminating and convergent validity, and sensitivity to change were rated sufficient to good. CONCLUSION: If the FR-instrument becomes part of regular ROM-procedures and is used as a measure of societal participation, it could be a useful addition to current measures of symptomatic remission.

Insight change in psychosis: relationship with neurocognition, social cognition, clinical symptoms and phase of illness.

OBJECTIVE: Impaired insight is an important and prevalent symptom of psychosis. It remains unclear whether cognitive disturbances hamper improvements in insight. We investigated the neurocognitive, social cognitive, and clinical correlates of changes in insight. METHOD: One hundred and fifty-four patients with a psychotic disorder were assessed at baseline (T0 ) and after three years (T3 ) with the Birchwood Insight Scale, the Positive And Negative Syndrome Scale, measures of neurocognition and social cognition. Linear regression analyses were conducted to examine to what extend neurocognition, social cognition, clinical symptoms and phase of illness could uniquely predict insight change. Subsequently, changes in these factors were related to insight change. RESULTS: Better neurocognitive performance and fewer clinical symptoms at baseline explained insight improvements. The additional effect of clinical symptoms over and above the contribution of neurocognition was significant. Together, these factors explained 10% of the variance. Social cognition and phase of illness could not predict insight change. Changes in clinical symptoms, but not changes in neurocognitive performance were associated with insight change. CONCLUSION: Neurocognitive abilities may predict, in part, the development of insight in psychosis.

Financial dissatisfaction in people with psychotic disorders - A short report on its prevalence and correlates in a large naturalistic psychosis cohort.

Psychotic disorders have a strong negative impact on multiple aspects of daily life, including people's financial situation. This exploratory study examines the level of financial dissatisfaction and its correlates in a large cohort of people with psychotic disorders. Data from the first assessments of people with psychotic disorders (n = 5271) who were included in the Pharmacotherapy Monitoring and Outcome Survey (PHAMOUS; 2006-2020), which is conducted in the northern Netherlands, were used. The Manchester Short Assessment of Quality of Life (MANSA) was used to measure financial dissatisfaction. In addition, sociodemographic and psychiatric characteristics, substance use and global and social functioning were assessed. One-fifth to one-third of people with psychotic disorders report financial dissatisfaction, fluctuating over the year in which they were assessed. These proportions are considerably higher than in the general population. Cannabis and other substance use were associated with higher levels of financial dissatisfaction (small to medium effect). The other significant associations showed (very) small effect sizes. Therefore, we conclude that financial dissatisfaction in people with psychotic disorders appears to be relatively independent of other demographic and psychiatric characteristics, and global and social functioning. These findings are an important first step for increasing knowledge on financial dissatisfaction among people with psychotic disorders. The findings can also contribute to raising awareness about the topic for healthcare professionals working in this field.

Self-stigma, religiosity, and perceived social support in people with recent-onset psychosis in the Islamic Republic of Iran: Associations with symptom severity and psychosocial functioning.

AIMS: Most evidence on psychosocial factors in recent-onset psychosis comes from high-income countries in Europe, Australia, Canada and the USA, while these factors are likely to differ under varying sociocultural and economic circumstances. In this study, we aimed to investigate associations of self-stigma, religiosity and perceived social support with symptom severity and psychosocial functioning in an Iranian cohort of people with recent-onset psychosis (i.e. illness duration of <2 years). METHODS: We used baseline data of 361 participants (N = 286 [74%] male, mean age = 34 years [Standard Deviation = 10.0]) from the Iranian Azeri Recent-onset Acute Phase Psychosis Survey (ARAS). We included assessments of self-stigma (Internalized Stigma of Mental Illness, ISMI), religiosity (based on Stark & Glock), perceived social support (Multidimensional Scale of Perceived Social Support, MSPSS), symptom severity (Positive And Negative Syndrome Scale, PANSS) and psychosocial functioning (clinician-rated Global Assessment of Functioning Scale, GAF, and self-reported World Health Organization Disability Assessment Schedule 2.0, WHODAS 2.0). Descriptive analyses were employed to characterize the study sample. Covariate-adjusted ordinal and multivariable linear regression analyses were performed to investigate cross-sectional associations of baseline ISMI, religiosity and MSPSS with concurrent PANSS, GAF and WHODAS 2.0. RESULTS: Higher self-stigma was associated with poorer self-reported functioning (B = 0.375 [95% Confidence Interval (CI): 0.186, 0.564]) and more severe concurrent symptoms (B = 0.436 [95% CI: 0.275, 0.597]). Being more religious was associated with poorer clinician-rated functioning (OR = 0.967 [95% CI: 0.944, 0.991]), but with less severe symptoms (B = -0.258 [95% CI: -0.427, -0.088]). Stronger social support was associated with poorer clinician-rated (OR = 0.956 [95% CI: 0.935, 0.978]) and self-reported functioning (B = 0.337 [95% CI: 0.168, 0.507]). CONCLUSION: This study shows that self-stigma, religiosity and perceived social support were associated with symptom severity and clinician-rated as well as self-reported psychosocial functioning in an Iranian cohort of people with recent-onset psychosis. The findings extend previous evidence on these psychosocial factors to one of the largest countries in the Middle East, and suggest that it may be worthwhile to develop strategies aimed at tackling stigma around psychosis and integrate the role of religiosity and social support in mental ill-health prevention and therapy.

ABCB1 gene variants influence tolerance to selective serotonin reuptake inhibitors in a large sample of Dutch cases with major depressive disorder.

P-glycoprotein (P-gp), an ATP-driven efflux pump in the blood-brain barrier, has a major impact on the delivery of antidepressant drugs in the brain. Genetic variants in the gene ABCB1 encoding for P-gp have inconsistently been associated with adverse effects. In order to resolve these inconsistencies, we conducted a study in a large cohort of patients with major depressive disorder with the aim to unravel the association of ABCB1 variants with adverse effects of antidepressants and in particular with selective serotonin reuptake inhibitors (SSRIs), which display affinity as substrate for P-gp. The Netherlands Study of Depression and Anxiety (NESDA) study was used as a clinical sample. For 424 patients data were available on drug use, side effects. We selected six ABCB1 gene variants (1236T>C, 2677G>T/A, 3435T>C, rs2032583, rs2235040 and rs2235015) and analyzed them for association with adverse drug effects using multinomial regression analysis for both single variants and haplotypes. We found a significant association between the number of SSRI-related adverse drug effects and rs2032583 (P=0.001), rs2235040 (P=0.002) and a haplotype (P=0.002). Moreover, serotonergic effects (sleeplessness, gastrointestinal complaints and sexual effects) were significantly predicted by these variants and haplotype (P=0.002/0.003). We conclude that adverse drug effects with SSRI treatment, in particular serotonergic effects, are predicted by two common polymorphisms of the ABCB1 gene.

Association between HTR2C gene polymorphisms and the metabolic syndrome in patients using antipsychotics: a replication study.

In two previous studies we found an association between HTR2C polymorphisms and the prevalence of the metabolic syndrome in patients using antipsychotics. In this study, we set out to replicate our findings in a third separate sample of patients. Data for this cross-sectional study came from the ongoing Pharmacotherapy Monitoring and Outcome survey study, investigating the association between schizophrenia and metabolic or cardiovascular risk factors. Primary end point was the prevalence of the metabolic syndrome. Primary determinants were two polymorphisms in the HTR2C gene: rs3813929 (-759 C/T) and rs1414334:C>G. Carriership of the variant rs1414334 C-allele was significantly associated with an increase prevalence of the metabolic syndrome (odds ratio (OR) 3.73; 95% confidence interval (CI) 1.29-10.79, P=0.015). No association was found between the HTR2C -759 C/T polymorphism and the metabolic syndrome. This study confirms previous findings that the variant C-allele of the rs1414334 polymorphism is associated with the metabolic syndrome.

Age at onset of non-affective psychosis in relation to cannabis use, other drug use and gender.

BACKGROUND: Cannabis use is associated with an earlier age at onset of psychotic illness. The aim of the present study was to examine whether this association is confounded by gender or other substance use in a large cohort of patients with a non-affective psychotic disorder. METHOD: In 785 patients with a non-affective psychotic disorder, regression analysis was used to investigate the independent effects of gender, cannabis use and other drug use on age at onset of first psychosis. RESULTS: Age at onset was 1.8 years earlier in cannabis users compared to non-users, controlling for gender and other possible confounders. Use of other drugs did not have an additional effect on age at onset when cannabis use was taken into account. In 63.5% of cannabis-using patients, age at most intense cannabis use preceded the age at onset of first psychosis. In males, the mean age at onset was 1.3 years lower than in females, controlling for cannabis use and other confounders. CONCLUSIONS: Cannabis use and gender are independently associated with an earlier onset of psychotic illness. Our findings also suggest that cannabis use may precipitate psychosis. More research is needed to clarify the neurobiological factors that make people vulnerable to this precipitating effect of cannabis.

Economic aspects of peer support groups for psychosis.

Peer support groups are rarely available for patients with psychosis, despite potential clinical and economic advantages of such groups. In this study, 106 patients with psychosis were randomly allocated to minimally guided peer support in addition to care as usual (CAU), or CAU only. No relevant differences between mean total costs of both groups were found, nor were there significant differences in WHOQoL-Bref outcomes. Intervention adherence had a substantial impact on the results. It was concluded that minimally guided peer support groups for psychosis do not seem to affect overall healthcare expenses. Positive results of additional outcomes, including a significant increase in social contacts and esteem support, favour the wider implementation of such groups.