Testing Ødegaard's selective migration hypothesis: a longitudinal cohort study of risk factors for non-affective psychotic disorders among prospective emigrants

BACKGROUND

The selection hypothesis posits that the increased rates of psychosis observed among migrants are due to selective migration of people who are predisposed to develop the disorder. To test this hypothesis, we examined whether risk factors for psychosis are more prevalent among future emigrants.

METHOD

A cohort of 49,321 Swedish military conscripts was assessed at age 18 years on cannabis use, IQ, psychiatric diagnosis, social adjustment, history of trauma and urbanicity of place of upbringing. Through data linkage we examined whether these exposures predicted emigration out of Sweden. We also calculated the emigrants' hypothetical relative risk compared with non-emigrants for developing a non-affective psychotic disorder.

RESULTS

Low IQ [odds ratio (OR) 0.5, 95% confidence interval (95% CI) 0.3-0.9] and 'poor social adjustment' (OR 0.4, 95% CI 0.2-0.8) were significantly less prevalent among prospective emigrants, whereas a history of urban upbringing (OR 2.3, 95% CI 1.4-3.7) was significantly more common. Apart from a non-significant increase in cannabis use among emigrants (OR 1.6, 95% CI 0.8-3.1), there were no major group differences in any other risk factors. Compared to non-emigrants, hypothetical relative risks for developing non-affective psychotic disorder were 0.7 (95% CI 0.4-1.2) and 0.8 (95% CI 0.7-1.0), respectively, for emigrants narrowly and broadly defined.

CONCLUSIONS

This study adds to an increasing body of evidence opposing the selection hypothesis.

[The genetics of antipsychotic-related movement disorders]

BACKGROUND

Treatment with antipsychotics is associated with movement disorders which are sometimes irreversible. It is therefore important to find ways of preventing the movements generated by the use of antipsychotics. Pharmacogenetic research is working on prevention strategies. The result of this research focus mainly on meta-analyses of association studies and genome-wide association studies (GWAS).

AIM

To present a review of the main pharmacogenetic studies of antipsychotic-related movement disorders.

METHOD

We reviewed the literature using Medline, Embase and PsycINFO.

RESULTS

Evidence from pooled data derived from meta-analyses showed small odds ratios between tardive dyskinesia (TD) and genes encoding DRD2, DRD3, BDNF, COMT, 5-HTR2A, CYP2D6, and MnSOD (p-value < 0.05). These results were not confirmed in DRDs and mnSOD by the most recent meta-analyses. GWAS for TD and parkinsonism have revealed new genes.

CONCLUSION

So far, we are unable to provide any clinically useful advice. New pharmacogenetic research and diagnostic systems are likely to create new opportunities.

[Functional remission of people with serious mental illness (SMI): psychometric properties of a new 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.

[Auto-immune disorders as a possible cause of neuropsychiatric syndromes]

BACKGROUND

Changes that occur in the behaviour of voltage-gated ion channels and ligand-gated receptor channels due to gene mutations or auto-immune attack are the cause of channelopathies in the central and peripheral nervous system. Although the relation between molecular channel defects and clinical symptoms has been explained in the case of many neuromuscular channelopathies, the pathophysiology of auto-immunity in neuropsychiatric syndromes is still unclear.

AIM

To review recent findings regarding neuronal auto-immune reactions in severe neuropsychiatric syndromes.

METHOD

Using PubMed, we consulted the literature published between 1990 and August 2014 relating to the occurrence of auto-immune antibodies in severe and persistent neuropsychiatric syndromes.

RESULTS

Auto-antibodies have only limited access to the central nervous system, but if they do enter the system they can, in some cases, cause disease. We discuss recent findings regarding the occurrence of auto-antibodies against ligand-activated receptor channels and potassium channels in neuropsychiatric and neurological syndromes, including schizophrenia and limbic encephalitis.

CONCLUSION

Although the occurrence of several auto-antibodies in schizophrenia has been confirmed, there is still no proof of a causal relationship in the syndrome. We still have no evidence of the prevalence of auto-immunity in neuropsychiatric syndromes. The discovery that an antibody against an ion channel is associated with some neuropsychiatric disorders may mean that in future it will be possible to treat patients by means of immunosuppression, which could lead to an improvement in a patient's cognitive abilities.

[Movement disorders as a prodromal sign in individuals at high risk of psychosis]

BACKGROUND

The accurate prediction of a transition to psychosis in high-risk and ultra-high-risk (UHR) populations is important because timely preventive interventions may succeed in delaying or even averting psychosis. However, current screening programmes have very low predictive power. Therefore, if prodromal signs are to be really useful they need to be objective and have strong predictive power. We hypothesise that in the prodromal phase movement disorders (MD) are probably better than screening programmes at predicting the development of psychotic disorders.

AIM

To determine, on the basis of published articles and personal experience, whether, in UHR populations, MD can predict a transition to psychosis more accurately that current screening programmes.

METHOD

We studied the literature using Medline.

RESULTS

Our strategy was to search the literature for studies concerning 1. children with schizotypal personality disorder, 2. UHR adolescents and 3. siblings of patients with schizophrenia. Studies relating to the first two groups showed that the severity of MD was related to the severity of the prodromal signs both at baseline and at follow-up. Patients with more (and more severe) MD had a higher risk of transition to a psychotic disorder than patients without MD. Studies relating to the third group showed that the frequency of mechanically measured md was significantly higher in the siblings of patients with schizophrenia than in healthy controls.

CONCLUSION

MD are objective easy-to-measure prodromal signs which might be powerful predictors of a transition to psychosis in (U)HR populations.

Factors contributing to the duration of untreated psychosis

BACKGROUND

Shortening the duration of untreated psychosis (DUP) - with the aim of improving the prognosis of psychotic disorders - requires an understanding of the causes of treatment delay. Current findings concerning several candidate risk factors of a longer DUP are inconsistent. Our aim was to identify factors contributing to DUP in a large sample that represents the treated prevalence of non-affective psychotic disorders.

METHOD

Patients with a non-affective psychotic disorder were recruited from mental health care institutes from 2004 to 2008. Of the 1120 patients enrolled, 852 could be included in the present analysis. Examined candidate factors were gender, educational level, migration status, premorbid adjustment and age at onset of the psychotic disorder. DUP was divided into five ordinal categories: less than one month, one month to three months, three months to six months, six months to twelve months and twelve months and over. An ordinal logistic regression analysis was used to identify the risk factors of a longer DUP.

RESULTS

Median DUP was less than one month (IQR 2). The factors migration status (p=0.028), age at onset of the psychotic disorder (p=0.003) and gender (p=0.034) were significantly associated with DUP in our analysis.

CONCLUSION

First generation immigrant patients, patients with an early onset of their psychotic disorder and male patients seem at risk of a longer DUP. These findings can assist in designing specific interventions to shorten treatment delay.

Does social defeat mediate the association between childhood trauma and psychosis? Evidence from the NEMESIS-2 Study

OBJECTIVE

Based on theoretical considerations and animal studies, mediation of 'social defeat' (SD) in the association between childhood trauma (CT) and psychosis was investigated.

METHOD

Trained interviewers administered a structured interview assessing CT, psychotic experiences and other psychopathology in 6646 participants in the second Netherlands Mental Health Survey and Incidence Study (NEMESIS-2).

RESULTS

Childhood trauma was associated with psychotic experiences making up the extended psychosis phenotype (EPP), as well as with a diagnosis of psychotic disorder (PD). Similarly, CT was associated with a priori selected items indexing SD (discouraged, hopeless, worthless, loss of self-confidence, low self-esteem, better off dead, suicidal thoughts) and with a measure of affective dysregulation (AD), which in turn were also associated with psychosis. While SD and AD individually acted as mediators in the association between CT and EPP, only SD acted as a mediator in the association between CT and PD. Cannabis use did not mediate the association between CT and EPP or PD.

CONCLUSION

The present results suggest a developmental model implicating SD as an important mediator in the link between childhood adverse experiences and later development of psychotic experiences. The combined mediation by SD and AD is compatible with an 'affective pathway' to early psychosis.

Therapygenetics in mindfulness-based cognitive therapy: do genes have an impact on therapy-induced change in real-life positive affective experiences?

Positive affect (PA) has an important role in resilience against depression and has been shown to increase with mindfulness-based cognitive therapy (MBCT). To elucidate the underlying mechanisms of change in PA as well as develop insights that may benefit personalized medicine, the current study examined the contribution of genetic variation to individual differences in change in PA in response to MBCT. Individuals (n=126) with residual depressive symptoms were randomized to either an MBCT group or treatment as usual. PA was assessed using experience sampling methodology (ESM). Single-nucleotide polymorphisms (SNPs) in genes known to be involved in reward functioning were selected. SNPs in the genes for brain-derived neurotrophic factor (BDNF), the muscarinic acetylcholine receptor M2 (CHRM2), the dopamine receptor D4 (DRD4) and the μ1 opioid receptor (OPRM1) significantly moderated the impact of treatment condition over time on PA. Genetic variation in the genes for CHRM2 and OPRM1 specifically had an impact on the level of PA following MBCT. The current study shows that variation in response to MBCT may be contingent on genetic factors associated with the regulation of PA. These findings contribute to our understanding of the processes moderating response to treatment and prediction of treatment outcome.

Positive emotions from social company in women with persisting subclinical psychosis: lessons from daily life

OBJECTIVE

Altered social reward functioning is associated with psychosis irrespective of stage and severity. Examining the role of social reward functioning prospectively in relation to psychotic experiences before these become persistent and potentially disabling can aid in elucidating social mechanisms that induce shifts toward more severe psychotic states, without the confounding effects of clinical disorder.

METHOD

In a longitudinal general population sample (N = 566), the experience sampling method (repetitive random sampling of momentary emotions and social context) was used to assess daily life social functioning at baseline. Persistence of subclinical psychotic experiences was based on the Community Assessment of Psychic Experiences assessed three times over 14 months. Analyses examined to what degree i) social context and ii) appreciation thereof differentiated between those who did and did not develop persistent psychotic experiences.

RESULTS

Although individuals with persistent psychotic experiences did not differ in overall level of positive effect, the amount of time spent alone or the level of social satisfaction compared to individuals without persistent psychotic experiences, they were more sensitive to the rewarding effects of social company.

CONCLUSION

Alterations in social reward experience may form one of the mechanisms that precede the development of the extended psychosis phenotype over time.

The Hong Kong mental morbidity survey: background and study design

Mental disorders are highly prevalent conditions with immense disease burden. To inform health and social services policy formulation, local psychiatric epidemiological data are required. The Hong Kong Mental Morbidity Survey is a 3-year population-based study in which 5700 community-dwelling Chinese adults aged between 16 and 75 years were interviewed with the aim of evaluating the prevalence, co-morbidity, functional impairment, physical morbidity, and social determinants of significant mental disorders in the population. This paper describes the background and design of the survey, and is the first territory-wide psychiatric epidemiological study in Hong Kong.

[The schizophrenia spectrum and other psychotic disorders in the DSM-5]

BACKGROUND

This article discusses changes made in the diagnostic criteria for psychotic disorders in the transition from DSM-IV to DSM-5.

AIM

To review and evaluate the changes incorporated in the DSM-5 criteria for psychotic disorders.

METHOD

Relevant documents and proceedings were reviewed on the basis of personal experience in the APA working group on psychotic disorders.

RESULTS

The chapter on the 'schizophrenia spectrum and other psychotic disorders' in DSM-5 introduces a conceptual psychosis continuum, in which the level, number and duration of psychotic signs and symptoms are used to differentiate between various forms of psychotic disorders. The chapter includes only a few marginal adjustments, aimed at simplifying usage and measurement-based treatment. The DSM-5 Committee also aspired for harmonization with the ICD. The Committee was in favor of a new name for schizophrenia, but referred the matter to the WHO. The empirical basis for 'attentuated psychosis syndrome' was found to be insufficient for the syndrome to be included as a diagnosis. The most important changes in the criteria for schizophrenia are the elimination of the classic subtypes, the clarification of cross-sectional and longitudinal course specifiers, the elimination of special status of Schneiderian first-rank symptoms, and the clarification and better delineation of schizophrenia in terms of: a) the relationship between schizophrenia and schizoaffective disorders and b) the relationship between schizophrenia and catatonia. In schizoaffective disorder, the perspective shifts from an episode diagnosis in DSM-IV to a life course for the illness in DSM-5. Although the committee gave serious consideration to the inclusion of trans-diagnostic dimensions, these have not been included; a factor that precludes more personalised diagnoses, at least for the time being.

CONCLUSION

The limitations of the classic system of categorical diagnosis are widely acknowledged and serious consideration has been given to the abolition of this type of diagnosis or at least to the possibility of enriching it with a transdiagnostic focus on dimensions of psychopathology. These steps have not been taken in DSM-5 - for the consensus committees this is evidently still a bridge too far.

Subclinical psychotic experiences and bipolar spectrum features in depression: association with outcome of psychotherapy

BACKGROUND

Subthreshold psychotic and bipolar experiences are common in major depressive disorder (MDD). However, it is unknown if effectiveness of psychotherapy is altered in depressed patients who display such features compared with those without. The current paper aimed to investigate the impact of the co-presence of subclinical psychotic experiences and subclinical bipolar symptoms on the effectiveness of psychological treatment, alone or in combination with pharmacotherapy.

METHOD

In a naturalistic study, patients with MDD (n = 116) received psychological treatment (cognitive behavioural therapy or interpersonal psychotherapy) alone or in combination with pharmacotherapy. Depression and functioning were assessed six times over 2 years. Lifetime psychotic experiences and bipolar symptoms were assessed at the second time point.

RESULTS

Subclinical psychotic experiences predicted more depression over time (β = 0.20, p < 0.002), non-remission [odds ratio (OR) 7.51, p < 0.016] and relapse (OR 3.85, p < 0.034). Subthreshold bipolar symptoms predicted relapse (OR 1.16, p < 0.037).

CONCLUSIONS

In general, subclinical psychotic experiences have a negative impact on the course and outcome of psychotherapy in MDD. Effects of subclinical bipolar experiences were less prominent.

Systematic review and collaborative recalculation of 133,693 incident cases of schizophrenia

BACKGROUND

This systematic review and collaborative recalculation was set up to recalculate schizophrenia incidence rates from previously published studies by age and sex.

METHOD

PubMed, EMBASE and PsycINFO databases were searched (January 1950 to December 2009) for schizophrenia incidence studies. Numerator and population data were extracted by age, sex and, if possible, study period. Original data were requested from the authors to calculate age- and sex-specific incidence rates. Incidence rate ratios (IRRs) with their 95% confidence intervals (CIs) were computed by age and sex from negative binomial regression models.

RESULTS

Forty-three independent samples met inclusion criteria, yielding 133 693 incident cases of schizophrenia for analysis. Men had a 1.15-fold (95% CI 1.00-1.31) greater risk of schizophrenia than women. In men, incidence peaked at age 20-29 years (median rate 4.15/10,000 person-years, IRR 2.61, 95% CI 1.74-3.92). In women, incidence peaked at age 20-29 (median rate 1.71/10,000 person-years, IRR 2.34, 95% CI 1.66-3.28) and 30-39 years (median rate 1.24/10,000 person-years, IRR 2.25, 95% CI 1.55-3.28). This peak was followed by an age-incidence decline up to age 60 years that was stronger in men than in women (χ² = 57.90, p < 0.001). The relative risk of schizophrenia was greater in men up to age 39 years and this reversed to a greater relative risk in women over the age groups 50-70 years. No evidence for a second incidence peak in middle-aged women was found.

CONCLUSIONS

Robust sex differences exist in the distribution of schizophrenia risk across the age span, suggesting differential susceptibility to schizophrenia for men and women at different stages of life.

Sexual minority status and psychotic symptoms: findings from the Netherlands Mental Health Survey and Incidence Studies (NEMESIS)

BACKGROUND

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.

METHOD

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.

RESULTS

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.

CONCLUSIONS

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.

Lessons learned from the psychosis high-risk state: towards a general staging model of prodromal intervention

BACKGROUND

The past two decades have seen exponential clinical and research interest in help-seeking individuals presenting with potentially prodromal symptoms for psychosis. However, the epidemiological validity of this paradigm has been neglected, limiting future advancements in the field.

METHOD

We undertook a critical review of core epidemiological issues underlying the clinical high-risk (HR) state for psychosis and which model of prodromal intervention is best suited for mental health.

RESULTS

The HR state for psychosis model needs refining, to bring together population-based findings of high levels of psychotic experiences (PEs) and clinical expression of risk. Traditionally, outcome has been attributed to 'HR criteria' alone rather than taking into account sampling strategies. Furthermore, the exclusive focus on variably defined 'transition' obscures true variation in the slow and non-linear progression across stages of psychopathology. Finally, the outcome from HR states is variable, indicating that the underlying paradigm of 'schizophrenia light progressing to schizophrenia' is inadequate.

CONCLUSIONS

In the general population, mixed and non-specific expression of psychosis, depression, anxiety and subthreshold mania is common and mostly transitory. When combined with distress, it may be considered as the first, diagnostically neutral stage of potentially more severe psychopathology, which only later may acquire a degree of diagnostic specificity and possible relative resistance to treatment. Therefore, rather than creating silos of per-disorder ultra-HR syndromes, an early intervention focus on the broad syndrome of early mental distress, requiring phase-specific interventions, may be more profitable.

Is psychotic disorder associated with increased levels of craving for cannabis? An Experience Sampling study

OBJECTIVE

Although cannabis use among individuals with psychotic disorder is considerable, little is known about patterns of use and factors contributing to continuation of use. Therefore, we investigated craving in relation to cannabis use in patients with psychotic disorder and healthy controls.

METHOD

The study included 58 patients with non-affective psychotic disorder and 63 healthy controls; all were frequent cannabis users. Craving was assessed with the Obsessive Compulsive Drug Use Scale (OCDUS) for cannabis, as well as in daily life using the Experience Sampling Method (ESM).

RESULTS

Patients scored higher on the OCDUS (B = 1.18, P = 0.022), but did not differ from controls in ESM indices of craving (all P > 0.05). In daily life, ESM craving predicted cannabis use and this was stronger in controls (χ(2) = 4.5, P = 0.033; Bcontrols = 0.08, P < 0.001; Bpatients = 0.06, P < 0.001). In both groups ESM craving was predicted by negative affect, paranoia, and hallucinations (Bnegativeaffect = 0.12, P = 0.009; Bparanoia = 0.13, P = 0.013; Bhallucinations = 0.13, P = 0.028), and followed by an increase in negative affect at non-cannabis-using moments (B = 0.03, P = 0.002).

CONCLUSION

The temporal dynamics of craving as well as craving intensity in daily life appear to be similar in patients and controls. Further research is needed to elucidate the inconsistencies between cross-sectional and daily-life measures of craving in psychosis.

Testing the estrogen hypothesis of schizophrenia: associations between cumulative estrogen exposure and cerebral structural measures

BACKGROUND

Bone mineral density (BMD), as an indicator of cumulative estrogen exposure, may be reduced in female patients with psychotic disorder (van der Leeuw et al., 2013), possibly reflecting reduced cerebral exposure to estrogen and alterations in neuroprotective effects. To the degree that BMD is a marker of cumulative (endogenous) estrogen exposure, we hypothesized that BMD would be positively associated with cerebral gray and white matter indices.

METHODS

Dual X-ray absorptiometry (DEXA) and magnetic resonance (MRI) scans were acquired in fourteen female patients diagnosed with a psychotic disorder. BMD was expressed in total BMD (g/cm(2)), Z- and T-scores. Cerebral cortical thickness (CT) (as indicator of gray matter status) and fractional anisotropy (FA) (as indicator of white matter integrity) were measured and served as the dependent variables in multilevel random regression models. BMD measures were the independent variables.

RESULTS

Femoral BMD measures were positively associated with CT at trend significance (total BMD: B=0.266, 95% CI: -0.019-0.552, p=0.067; Z-score: B=0.034, 95% CI: 0.001-0.067, p=0.046; T-score: B=0.034, 95% CI: 0.000-0.068, p=0.052). There were no significant associations between femoral BMD measures and FA.

CONCLUSIONS

The data suggest that in women with psychotic disorder, alterations in the neuroprotective effect of estrogen (as measured by BMD) impact cortical gray matter, but not white matter integrity. These findings merit further investigation and, if replicated, would lend support to the estrogen hypothesis of schizophrenia.

Resilience in mental health: linking psychological and neurobiological perspectives

OBJECTIVE

To review the literature on psychological and biological findings on resilience (i.e. the successful adaptation and swift recovery after experiencing life adversities) at the level of the individual, and to integrate findings from animal and human studies.

METHOD

Electronic and manual literature search of MEDLINE, EMBASE and PSYCHINFO, using a range of search terms around biological and psychological factors influencing resilience as observed in human and experimental animal studies, complemented by review articles and cross-references.

RESULTS

The term resilience is used in the literature for different phenomena ranging from prevention of mental health disturbance to successful adaptation and swift recovery after experiencing life adversities, and may also include post-traumatic psychological growth. Secure attachment, experiencing positive emotions and having a purpose in life are three important psychological building blocks of resilience. Overlap between psychological and biological findings on resilience in the literature is most apparent for the topic of stress sensitivity, although recent results suggest a crucial role for reward experience in resilience.

CONCLUSION

Improving the understanding of the links between genetic endowment, environmental impact and gene-environment interactions with developmental psychology and biology is crucial for elucidating the neurobiological and psychological underpinnings of resilience.

An incidence study of diagnosed autism-spectrum disorders among immigrants to the Netherlands

OBJECTIVE

To estimate the risk of developing autism-spectrum disorder (ASD) in children born to immigrants as compared with children of Dutch-born parents.

METHOD

Retrospective, population-based cohort study of all live births (n = 106 953) between 1998 and 2007 in a circumscribed geographical region in the Netherlands. Cohort members were linked to the Psychiatric Case Register to identify diagnosed cases.

RESULTS

A total of 518 cases of ASD were identified, including 150 children with autism and 368 children with Asperger syndrome or Pervasive Developmental Disorder Not Otherwise Specified (PDD-NOS). Children born to migrants from developing countries were at significantly lower risk of ASD [rate ratio (RR) = 0.6, 95% confidence interval (CI) 0.5-0.9] than children of Dutch-born parents. Within the ASD group, the risk for the subgroup with Asperger syndrome and PDD-NOS was reduced (RR = 0.4, 95% CI 0.3-0.6), whereas that for narrowly defined autism was non-significantly increased (RR = 1.4, 95% CI 0.9-2.4). Migrant groups did not differ in age at diagnosis.

CONCLUSION

The results echo Swedish findings indicating a reversal of risk gradient in children of parents from developing countries, specifically a decreased risk for high-functioning and increased risk for low-functioning autism.

Increased stress reactivity: a mechanism specifically associated with the positive symptoms of psychotic disorder

BACKGROUND

An increased reactivity to stress in the context of daily life is suggested to be an independent risk factor underlying the positive symptoms of psychotic disorder. The aim of this study was to investigate whether positive symptoms moderate the association between everyday stressful events and negative affect (NA), known as stress reactivity. This hypothesis was put to the test in patients with a diagnosis of psychotic disorder. Method The Comprehensive Assessment of Symptoms and History (CASH) and the Positive and Negative Syndrome Scale (PANSS) were used to assess positive and negative symptoms. The experience sampling method (ESM), a structured diary technique, was used to measure stress reactivity and psychotic symptoms in daily life.

RESULTS

Higher levels of positive symptoms (CASH: B = 0.14, p = 0.005; PANSS: B = 0.05, p = 0.000; ESM: B = 0.03, p = 0.000) and lower levels of negative symptoms (PANSS: B = - 0.05, p = 0.001) significantly moderate the association between unpleasant events and NA. No significant moderating effect was found for CASH negative symptoms. Moreover, the moderating effect of lifetime and current symptoms on the stress-NA association was significantly larger for those patients with predominantly positive symptoms (CASH: B = 0.09, p = 0.000; PANSS: B = 0.08, p = 0.000; ESM: B = 0.13, p = 0.000).

CONCLUSIONS

Patients with a 'psychotic syndrome' with high levels of positive symptoms and low levels of negative symptoms show increased reactivity to stress in daily life, indicating that stress reactivity is a possible risk factor underlying this syndrome.

An updated and conservative systematic review and meta-analysis of epidemiological evidence on psychotic experiences in children and adults: on the pathway from proneness to persistence to dimensional expression across mental disorders

BACKGROUND

The psychosis-proneness-persistence-impairment model of psychotic disorder incorporates notions of both phenomenological and temporal continuity (persistence) of psychotic experiences (PE), but not structural continuity. Specific testable propositions of phenomenological continuity and persistence are identified. Method Propositions are tested by systematic reviews of the epidemiology of PE, persistence of PE and disorder outcomes, and meta-analyses (including Monte Carlo permutation sampling, MCPS) of reported rates and odds ratios (ORs).

RESULTS

Estimates of the incidence and prevalence of PE obtained from 61 cohorts revealed a median annual incidence of 2.5% and a prevalence of 7.2%. Meta-analysis of risk factors identified age, minority or migrant status, income, education, employment, marital status, alcohol use, cannabis use, stress, urbanicity and family history of mental illness as important predictors of PE. The mode of assessment accounted for significant variance in the observed rates. Across cohorts, the probability of persistence was very strongly related to the rate of PE at baseline. Of those who report PE, ∼20% go on to experience persistent PE whereas for ∼80%, PE remit over time. Of those with baseline PE, 7.4% develop a psychotic disorder outcome.

CONCLUSIONS

Compelling support is found for the phenomenological and temporal continuity between PE and psychotic disorder and for the fundamental proposition that this relationship is probabilistic. However, imprecision in epidemiological research design, measurement limitations and the epiphenomenological nature of PE invite further robust scrutiny of the continuity theory.

Deconstructing the familiality of variability in momentary negative and positive affect

OBJECTIVE

The daily life, affective phenotypes of momentary negative affect (NA), positive affect (PA) variability and NA variability are associated with future depressive symptomatology. This study investigates the extent to which genetic and environmental factors contribute to the inter-individual differences in these daily life, affective phenotypes.

METHOD

Two hundred and seventy-nine female twins from the Flemish (Belgium) general population participated in an experience sampling study measuring affect in daily life. Structural equation modelling was used to fit univariate and bivariate models.

RESULTS

Genetic factors explained, respectively, 18%, 18% and 35% of the inter-individual differences in momentary NA, PA variability and NA variability. Non-shared environmental factors were found to explain the remaining inter-individual variation. In addition, 41% of the association between positive and NA variability was attributed to shared genetic factors.

CONCLUSION

Results of this study show that daily life patterns of affective expression are subject to substantial environmental influence. Prospective assessments of the effect of interventions on these expressions may therefore represent a powerful tool to prevent transition from subclinical depressive symptomatology to a clinical outcome or to reduce symptomatology in those with clinical depression.

Unemployment, ethnicity and psychosis

OBJECTIVE

This study describes the incidence of psychosis in unemployed people and determines whether unemployment has a greater impact on the development of psychosis amongst Black minority groups than White groups.

METHOD

Patients with a first diagnosis of Research Diagnostic Criteria psychosis, in a defined area of London from 1998 to 2004, were identified. Crude and standardised incidence rates of psychosis amongst unemployed people for each ethnic group were calculated. Poisson regression modelling tested for interactions between unemployment and ethnicity.

RESULTS

Hundred cases occurred amongst employed people and 78 cases occurred amongst the unemployed people. When standardised to the employed White population of the area, White unemployed people had a standardised incidence ratio (SIR) of 11.7 (95% CI 6.4-19.7), Black Caribbean people had a SIR of 60.1(95% CI 39.3-88) and Black African people had a SIR of 40.7 (95% CI 25.8-61.1). There was no interaction however between ethnicity and unemployment (Likelihood ratio test P = 0.54).

CONCLUSION

Rates of psychosis are high amongst unemployed people in south London and extremely high amongst Black Caribbean and Black African unemployed people. There was no evidence however that the minority groups were particularly sensitive to the stresses, limitations or meaning of unemployment.

[Effects on scale and confidence intervals as alternatives to p < 0.05]

BACKGROUND

Researchers and reviewers often use the conventional p < 0.05 as threshold in statistical tests. In many cases, however, the interpretation of p-values is incorrect.

AIM

To explain where the 5% norm originates, identify the interpretation problems that often arise and suggest some alternatives.

METHOD

On the basis of recent literature we examine the meaning and origin of the p < 0.05 norm. We looked closely at entire articles and short reports in the Tijdschrift voor Psychiatrie, starting with the Jubilee issue of 2008, in order to find examples of methodological problems relating to the routine use of p-values.

RESULTS

We found several examples of the problematic use of p-values; these included the testing of a priori unlikely, or even impossible null hypotheses, the reporting of small effects calculations based on erroneous assumptions, and incorrect interpretations of statistical parameters and p-values.

CONCLUSION

Research in psychiatry, like research in other disciplines, attaches too much weight to p-values. Guidelines for authors should advise authors to focus explicitly on effect sizes, confidence intervals and the scale on which the results are presented.

Bone mineral density as a marker of cumulative endogenous estrogen exposure: relationship to background genetic risk of psychotic disorder

BACKGROUND

Alterations in bone mineral density (BMD) in patients with psychotic disorder may reflect the effect of treatment (disease effect observed in patients but not their siblings) or, as an intermediate marker of cumulative endogenous estrogen exposure, alterations in the neuroprotective effect of estrogen in the brain (vulnerability effect observed in patients and siblings).

METHODS

Dual X-ray absorptiometry (DEXA) scans were acquired in 62 patients with a psychotic disorder, 67 non-psychotic siblings of patients with a psychotic disorder, and 48 controls. BMD (g/cm(2)), Z-scores and T-scores were measured in the lumbar spine and proximal femur. Associations between group and BMD were investigated with multilevel random regression analyses. Group×sex interactions and effects of antipsychotic medication (AP) on BMD were examined.

RESULTS

Group was not associated with BMD outcome measures, although patients had consistently lower BMD measures compared to both siblings and controls. There were no significant group×sex interactions, but stratified analyses showed that BMD measures in female patients were significantly lower in comparison to female controls and siblings (e.g. total femoral BMD, P vs. C: B=-0.100, p=0.010; P vs. S: B=-0.104, p=0.008). After excluding female patients who used prolactin-raising AP, the effect was attenuated (e.g. total femoral BMD, P vs. C: B=-0.073, p=0.072; P vs. S: B=-0.085, p=0.051). In men, there were no significant BMD differences between patients and controls.

CONCLUSION

Familial risk of psychotic disorder was not associated with BMD. Instead, decreased BMD in the femur may reflect treatment effects or non-familial risk associated with low cumulative endogenous estrogen levels in women.

Testing the hypothesis that psychotic illness begins when subthreshold hallucinations combine with delusional ideation

OBJECTIVE

While hallucinations and delusions are often considered as a single class of 'positive symptoms', little is known about their dynamic cooccurrence in relation to clinical outcome in non-help-seeking people.

METHOD

The Netherlands Mental Health and Incidence Study (NEMESIS-1) is a longitudinal study of mental disorders (n = 7075) with three measurements over a 3-year period. Risk factors, persistence of psychotic experiences, and clinical outcome were analyzed for groups with: i) no psychotic experiences, ii) only delusions, iii) only hallucinations, and iv) both delusions and hallucinations.

RESULTS

Hallucinations and delusions occurred together more often (T0, 3.5%; T1, 1.0%; T2, 0.9%) than that predicted by chance (T0, 1.0%; T1, 0.1%; T2, 0.04%). The group with both symptoms showed more 'first-rank'-like delusions compared with the group with only delusions. Having both hallucinations and delusions, compared to isolated symptoms, was associated more strongly with risk factors, comorbid affective symptoms, negative symptoms, and persistence of psychotic experiences. This was not an artifact of having more symptoms in general.

CONCLUSION

Experiencing both delusions and hallucinations is an indicator of greater etiological load resulting in more clinical outcome. A specific 'hallucinatory-delusional state' may represent an early phase of exacerbation of aberrant attribution of salience, increasing risk for clinical outcome.

Evidence that the wider social environment moderates the association between familial liability and psychosis spectrum outcome

BACKGROUND

Familial liability to both severe and common mental disorder predicts psychotic disorder and psychotic symptoms, and may be used as a proxy in models examining interaction between genetic risk and the environment at individual and contextual levels.

METHOD

In a representative general population sample (n=4011) in Izmir, Turkey, the full spectrum of expression of psychosis representing (0) no symptoms, (1) subclinical psychotic experiences, (2) low-impact psychotic symptoms, (3) high-impact psychotic symptoms and (4) full-blown clinical psychotic disorder was assessed in relation to mental health problems in the family (proxy for familial liability) and the wider social environment. Quality of the wider social environment was assessed in an independent sample using contextual measures of informal social control, social disorganization, unemployment and low income, aggregated to the neighbourhood level.

RESULTS

The association between familial liability to severe mental illness and expression of psychosis spectrum was stronger in more deprived neighbourhoods [e.g. this association increased from β=0.33 (p=0.01) in low-unemployment neighbourhoods to β=0.92 (p<0.001) in high-unemployment neighbourhoods] and in neighbourhoods high in social control, while neighbourhood variables did not modify the association between familial liability to common mental disorder and the psychosis outcome. Neighbourhood variables mediated urbanicity effects.

CONCLUSIONS

Contextual effects may be important in moderating the expression of psychosis liability in populations, representing a specific pathway independent of the link between common mental disorder and psychosis.

Emotion recognition in psychosis: no evidence for an association with real world social functioning

BACKGROUND

Patients with psychotic disorders show impairments in the recognition of emotions in other people. These impairments have been associated with poor social functioning as measured by self-report questionnaires, clinical interviews and laboratory-based tests of social skills. The ecological validity of these tests, however, is low. Associations were examined between emotion recognition and daily life social interactions in 50 patients diagnosed with a non-affective psychotic disorder and 67 healthy controls.

METHODS

All participants were assessed with the Degraded Facial Affect Recognition Task (DFAR), a computer test measuring the recognition of emotional facial expressions. Social functioning in daily life was assessed using the Experience Sampling Method (a random time sampling technique) with focus on measures of social context and appraisal of the social situation.

RESULTS

Groups differed significantly in the recognition of angry faces, whereas no differences existed for other emotions. There were no associations between emotion recognition and social functioning in daily life and there was no evidence for differential associations in patients as compared to controls.

DISCUSSION

Social functioning, when assessed in an ecologically valid fashion, is not sensitive to variation in the traditional experimental assessment of emotion recognition. Real life measures of functioning should guide research linking the handicaps associated with psychosis to underlying cognitive and emotional dysregulation.

Do subthreshold psychotic experiences predict clinical outcomes in unselected non-help-seeking population-based samples? A systematic review and meta-analysis, enriched with new results

BACKGROUND

The base rate of transition from subthreshold psychotic experiences (the exposure) to clinical psychotic disorder (the outcome) in unselected, representative and non-help-seeking population-based samples is unknown.

METHOD

A systematic review and meta-analysis was conducted of representative, longitudinal population-based cohorts with baseline assessment of subthreshold psychotic experiences and follow-up assessment of psychotic and non-psychotic clinical outcomes.

RESULTS

Six cohorts were identified with a 3-24-year follow-up of baseline subthreshold self-reported psychotic experiences. The yearly risk of conversion to a clinical psychotic outcome in exposed individuals (0.56%) was 3.5 times higher than for individuals without psychotic experiences (0.16%) and there was meta-analytic evidence of dose-response with severity/persistence of psychotic experiences. Individual studies also suggest a role for motivational impairment and social dysfunction. The evidence for conversion to non-psychotic outcome was weaker, although findings were similar in direction.

CONCLUSIONS

Subthreshold self-reported psychotic experiences in epidemiological non-help-seeking samples index psychometric risk for psychotic disorder, with strong modifier effects of severity/persistence. These data can serve as the population reference for selected and variable samples of help-seeking individuals at ultra-high risk, for whom much higher transition rates have been indicated.

Do we need a European consensus on the use of antipsychotic medication?

Recently, much effort has been directed towards reaching a consensus on the use of antipsychotic medication in the United Kingdom (UK) and in France. Anecdotal evidence suggests, however, that any differences that may exist between practitioners in the UK are only minor in comparison to those between practitioners in the various countries in the European Union. A comparison was conducted of the number of prescribed antipsychotic compounds, as well as their way of administration, in two samples of schizophrenic patients in the UK and France. French patients were much more likely to have been prescribed two or more antipsychotic compounds, either alone (relative risk: RR = 26.3; 95% CI: 3.8-190.6), or in combination with a depot preparation (RR = infinity; Fisher's exact test P = 0.04). British patients were more likely to have been prescribed a single depot preparation (RR = 4.7; 95% CI: 2.3-9.9). These disparities are related to contrasting views on the properties and indications of antipsychotics in the two countries. Given these disparities, working towards a European consensus appears essential.

Cognitive functioning and age at onset in non-affective psychotic disorder

OBJECTIVE

Age at psychosis onset has been related to variability in cognitive functioning, but its effect may be mediated by demographic and clinical factors. The aim of the current study was to study the contribution of age at onset, as well as demographic and illness characteristics, to variation in cognitive functioning in patients with schizophrenia spectrum disorder.

METHOD

Patients (n = 1053) and healthy controls (n = 631) underwent comprehensive neuropsychological and clinical assessments. The effect of age at onset on age-standardized cognitive test scores was assessed with multiple linear regression analyses. Mediation by illness and demographic factors was tested using a multiple mediation Sobel test.

RESULTS

A diagnosis of schizophrenia, higher antipsychotic dose, and more negative symptoms were associated with earlier onset of illness, while female sex and a more chronic course were associated with later illness onset. Furthermore, earlier onset was associated with worse performance on immediate recall and sustained attention. However, male sex, more negative symptoms, and higher antipsychotic dose mediated the effect of age at onset on memory, while negative symptoms explained its association with attention/vigilance.

CONCLUSION

Greater impairment in memory and attention in early-onset psychosis may be explained by features indicative of underlying neurodevelopmental vulnerability.

Early trauma and familial risk in the development of the extended psychosis phenotype in adolescence

OBJECTIVE

Both genetic and environmental factors are thought to play a role in the development of psychotic outcomes; however, their respective contributions over time, including possible developmental interactions, remain largely unknown.

METHOD

The contribution of parental general and psychotic psychopathology as proxies of genetic risk to the development of subthreshold psychosis and its hypothesized interaction with childhood trauma were studied in a general population sample of 2230 adolescents, followed from age 10-16 years. Outcome measures were: i) level of psychotic experiences at age 16 years and ii) persistence of such experiences over the total follow-up period.

RESULTS

General parental psychopathology was associated with CAPE score (OR = 1.08; P < 0.043 for highest quintile) and suggestively predicted psychosis persistence (OR, 1.16; P < 0.072). Psychotic parental psychopathology was suggestively associated with CAPE score (OR, 2.25; P < 0.063 for highest quintile), predicted membership of the Persistent group (OR, 3.72; P < 0.039) and suggestively predicted membership of the Decreasing group (OR 2.04; P < 0.051). Childhood trauma was associated with CAPE score and with all developmental trajectories of subclinical psychosis. No evidence was found for an interaction between trauma and parental psychopathology.

CONCLUSION

The development and persistence of subthreshold psychotic symptoms may be conditional on non-interacting proxy genetic and environmental influences.

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.

Symptomatic remission in psychosis and real-life functioning

BACKGROUND

In 2005 Andreasen proposed criteria for remission in schizophrenia. It is unclear whether these criteria reflect symptom reduction and improved social functioning in daily life.

AIMS

To investigate whether criteria for symptomatic remission reflect symptom reduction and improved functioning in real life, comparing patients meeting remission criteria, patients not meeting these criteria and healthy controls.

METHOD

The Experience Sampling Method (ESM), a structured diary technique, was used to explore real-life symptoms and functioning in 177 patients with (remitted and non-remitted) schizophrenia spectrum disorders and 148 controls.

RESULTS

Of 177 patients, 70 met criteria for symptomatic remission. These patients reported significantly fewer positive and negative symptoms and better mood states compared with patients not in remission. Furthermore, patients in remission spent more time in goal-directed activities and had less preference for being alone when they were with others. However, the patient groups did not differ on time spent in social company and doing nothing, and both the remission and non-remission groups had lower scores on functional outcome measures compared with the control group.

CONCLUSIONS

The study provides an ecological validation for the symptomatic remission criteria, showing that patients who met the criteria reported fewer positive symptoms, better mood states and partial recovery of reward experience compared with those not in remission. However, remission status was not related to functional recovery, suggesting that the current focus on symptomatic remission may reflect an overly restricted goal.

Pituitary volume, stress reactivity and genetic risk for psychotic disorder

BACKGROUND

Hypothalamic-pituitary-adrenal (HPA) axis hyperactivity, associated with increased pituitary volume, may mediate observed alterations in stress reactivity in patients with psychotic disorder. We examined the association between pituitary volume, real-life stress reactivity and genetic liability for psychotic disorder.

METHOD

Pituitary volumes were derived from magnetic resonance imaging (MRI) scans of 20 patients with psychotic disorder, 37 non-psychotic siblings of these patients, and 32 controls. The Experience Sampling Method (ESM) was used to measure emotional stress reactivity [changes in negative affect (NA) associated with daily life stress] in the three groups, and biological stress reactivity (changes in cortisol associated with daily life stress) in siblings and controls. Interactions between group, stress and pituitary volume in models of NA and cortisol were examined.

RESULTS

Groups did not differ in pituitary volume. Patients showed significantly higher emotional stress reactivity than siblings and controls. In addition, emotional stress reactivity increased with increasing pituitary volume to a greater degree in patients than in controls and siblings. Siblings had higher cortisol levels than controls but did not show increased cortisol reactivity to stress. There was no interaction between pituitary volume, stress and group in the model of cortisol.

CONCLUSIONS

Higher pituitary volume was associated with increased emotional stress reactivity in patients with psychotic disorder, siblings and controls. The association was significantly stronger in the patient group, suggesting a process of progressive sensitization mediating clinical outcome.

Adversity and psychosis: a 10-year prospective study investigating synergism between early and recent adversity in psychosis

OBJECTIVE

Recent studies have suggested that early adverse events, such as childhood trauma, may promote enduring liability for psychosis whereas more recent adverse events may act as precipitants. Examination of these environmental dynamics, however, requires prospective studies in large samples. This study examines whether the association between recent adverse events and psychosis is moderated by exposure to early adversity.

METHOD

A random regional representative population sample of 3021 adolescents and young adults in Munich, Germany, was assessed three times over a period of up to 10 years, collecting information on sociodemographic factors, environmental exposures, and measures of psychopathology and associated clinical relevance. Evidence of statistical non-additivity between early adversity (two levels) and more recent adversity (four levels) was assessed in models of psychotic symptoms. Analyses were a priori corrected for age, gender, cannabis use, and urbanicity.

RESULTS

Early and recent adversity were associated with each other (RR = 1.32, 95% CI 1.06-1.66; P = 0.014) and displayed statistical non-additivity at the highest level of exposure to recent adversity (χ(2) = 4.59; P = 0.032).

CONCLUSION

The findings suggest that early adversity may impact on later expression of psychosis either by increasing exposure to later adversity and/or by rendering individuals more sensitive to later adversity if it is severe.

Evidence that interactive effects of COMT and MTHFR moderate psychotic response to environmental stress

OBJECTIVE

A functional interaction between Catechol-O-Methyltransferase (COMT) Val158Met and methylenetetrahydrofolate reductase (MTHFR) C677T has been shown to differentially affect cognition in patients with schizophrenia and healthy controls; the effect of COMT Val158Met × MTHFR interaction on resilience to stress in patients and controls remains to be examined.

METHOD

A total of 98 patients with non-affective psychotic disorder and 118 controls were genotyped for MTHFR C677T, MTHFR A1298C, and COMTVal158Met. Daily life reactivity to stress, modelled as the effect of daily life stress on psychotic experiences, was measured using the experience sampling method (ESM).

RESULTS

The MTHFR C677T genotype moderated the interaction between COMT Val158Met genotype and stress in patients (P < 0.0001), but not in controls (P = 0.68). Further examination of this interaction revealed that in patients with the MTHFR 677 T-allele, COMT Met/Met individuals displayed the largest increases in psychotic symptoms in reaction to ESM stress [χ(2)(2) = 29.51; P < 0.0001], whereas in patients with the MTHFR 677 C/C genotype no significant COMT Val158Met × ESM stress interaction was apparent [χ(2)(2) = 3.65; P = 0.16]. No moderating effect of MTHFR A1298C was found.

CONCLUSION

Stress reactivity associated with COMT Val158Met in patients with psychosis may crucially depend on MTHFR C677T genotype.

The association between social phobia, social anxiety cognitions and paranoid symptoms

OBJECTIVE

Previous research suggests high levels of comorbidity between social phobia and paranoid symptoms, although the nature of this association remains unclear.

METHOD

Data were derived from the Early Developmental Stages of Psychopathology study, a 10-year longitudinal study in a representative German community sample of 3021 participants aged 14-24 years at baseline. The Munich-Composite International Diagnostic Interview was used to assess social phobia and paranoid symptoms, along with data on social phobia features. Cross-sectional and longitudinal analyses were conducted. Differential associations with environmental risk factors and temperamental traits were investigated.

RESULTS

Lifetime social phobia and paranoid symptoms were associated with each other cross-sectionally (OR = 1.80, 95% CI = 1.31-2.47). Lifetime paranoid symptoms were associated specifically with social anxiety cognitions. Lifetime cognitions of negative evaluation predicted later onset of paranoid symptoms, whereas onset of social phobia was predicted by cognitions of loss of control and fear/avoidance of social situations. Lifetime social phobia and paranoid symptoms shared temperamental traits of behavioural inhibition, but differed in environmental risks.

CONCLUSIONS

The present study showed that paranoid symptoms and social phobia share similarities in cognitive profile and inhibited temperament. Avoidance appears to be important in the development of social phobia, whereas cannabis use and traumatic experiences may drive paranoid thinking in vulnerable individuals.

Auditory hallucinations in childhood: associations with adversity and delusional ideation

BACKGROUND

Previous work suggests that exposure to childhood adversity is associated with the combination of delusions and hallucinations. In the present study, associations between (severity of) auditory vocal hallucinations (AVH) and (i) social adversity [traumatic experiences (TE) and stressful events (SE)] and (ii) delusional ideation were examined.

METHOD

A baseline case-control sample of children with and without AVH were re-assessed on AVH after 5 years and interviewed about the experience of social adversity and delusions.

RESULTS

A total of 337 children (mean age 13.1 years, S.D.=0.5) were assessed: 40 children continued to hear voices that were present at baseline (24%, persistent group), 15 heard voices only at follow-up (9%, incident group), 130 children no longer reported AVH that were present at baseline (remitted group) and 152 never heard voices (referent group). Both TE and SE were associated with both incident and persistent AVH, as well as with greater AVH severity and delusional ideation at follow-up. In addition, the combination of AVH and delusions displayed a stronger association with TE and SE compared with either AVH or delusions alone.

CONCLUSIONS

Early childhood AVH are mostly benign and transitory. However, experience of social adversity is associated with persistence, severity and onset of new AVH closer to puberty, and with delusional ideation.

Evidence that genes for depression impact on the pathway from trauma to psychotic-like symptoms by occasioning emotional dysregulation

BACKGROUND

Genes for depression may act by making individuals more sensitive to childhood trauma. Given that childhood adversity is a risk factor for adult psychosis and symptoms of depression and psychosis tend to cluster within individuals and families, the aim was to examine whether the association between childhood adversity and psychotic-like symptoms is moderated by genetic liability for depression. A secondary aim was to determine to what degree a depression-related increase in stress sensitivity or depressive symptoms themselves occasioned the moderating effect.

METHOD

Female twins (n=508) completed both prospective and retrospective questionnaires regarding childhood adversity [the Symptom Checklist-90 - Revised (SCL-90-R) and SCID-I (psychotic symptoms)] and psychotic trait liability [the Community Assessment of Psychic Experiences (CAPE)]. Stress sensitivity was indexed by appraisals of event-related stress and negative affect (NA) in the flow of daily life, assessed with momentary assessment technology for five consecutive days. Multilevel regression analyses were used to examine moderation of childhood adversity by genetic liability for depression in the prediction of follow-up psychotic experiences.

RESULTS

The effect of childhood adversity was significantly moderated by genetic vulnerability for depression in the model of both follow-up psychotic experiences (SCL-90-R) and follow-up psychotic trait liability (CAPE). The moderation by genetic liability was mediated by depressive experience but not by stress sensitivity.

CONCLUSIONS

Genetic liability for depression may potentiate the pathway from childhood adversity to psychotic-like symptoms through dysfunctional emotional processing of anomalous experiences associated with childhood trauma.

Self-monitoring as a familial vulnerability marker for psychosis: an analysis of patients, unaffected siblings and healthy controls

BACKGROUND

Alterations in self-monitoring have been reported in patients with psychotic disorders, but it remains unclear to what degree they represent true indicators of familial vulnerability for psychosis.

METHOD

An error-correction action-monitoring task was used to examine self-monitoring in 42 patients with schizophrenia, 32 of their unaffected siblings and 41 healthy controls.

RESULTS

Significant between-group differences in self-monitoring accuracy were found (χ2=29.3, p<0.0001), patients performing worst and unaffected siblings performing at an intermediate level compared to controls (all between-group differences p<0.05). In the combined group of healthy controls and unaffected siblings, detection accuracy was associated with positive schizotypy as measured by the Structured Interview for Schizotypy - Revised (SIS-R) (β=-0.16, s.e.=0.07, p=0.026), but not with negative schizotypy (β=-0.05, s.e.=0.12, p=0.694). In patients, psychotic symptoms were not robustly associated with detection accuracy (β=-0.01, s.e.=0.01, p=0.094), although stratified analysis revealed suggestive evidence for association in patients not currently using antipsychotic medication (β=-0.03, s.e.=0.01, p=0.052), whereas no association was found in patients on antipsychotic medication (β=-0.01, s.e.=0.01, p=0.426). A similar pattern of associations was found for negative symptoms.

CONCLUSIONS

Alterations in self-monitoring may be associated with familial risk and expression of psychosis. The association between psychotic symptoms and self-monitoring in patients may be affected by antipsychotic medication, which may explain previous inconsistencies in the literature.

Risk of psychiatric treatment for mood disorders and psychotic disorders among migrants and Dutch nationals in Utrecht, The Netherlands

PURPOSE

While there are consistent reports of a high psychosis rate among certain groups of migrants in Europe, there is little information on their risk for mood disorders. The aim of this study was to investigate the risk of receiving psychiatric treatment for mood disorders or psychotic disorders, comparing migrants and Dutch nationals in an ethnically mixed catchment area. A second aim was to calculate the 1-year prevalence rates of psychotic disorders in first-generation migrants.

METHOD

A psychiatric registry provided information on treatments at all in- and outpatient facilities. Statistics Netherlands provided annual population figures.

RESULTS

The risk of receiving treatment for unipolar depressive disorder was increased for the Turkish-Dutch (first and second generation combined; age- and sex-adjusted relative risk 4.9; 95% CI: 4.4-5.5), Moroccan-Dutch (RR = 3.6; 3.3-4.0) and Surinamese-Dutch (RR=1.8; 1.5-2.2). The risk of being treated for bipolar disorder was not significantly increased for any group, except for the Turkish-Dutch of the second generation. The risk of treatment for non-affective psychotic disorder was very high for the Turkish-Dutch, Moroccan-Dutch and Surinamese-Dutch of the second generation. There was a large difference in the relative risk of this disorder between the Turkish-Dutch of the first (RR = 1.3; 1.0-1.8) and the second generation (RR = 8.7; 5.5-13.9). The 1-year prevalence rates of treated psychotic disorders were highest for Surinamese-Dutch (2.1%) and Moroccan-Dutch males (1.2%) of the first generation. Migrants from western-European countries were not at increased risk for any of these disorders.

CONCLUSIONS

The stressful position of non-Western migrants in Dutch society has negative consequences on their mental health.

[Staging and profiling of psychiatric disorders]

BACKGROUND

Diagnostic issues are at the heart of medicine. Although the existing systems to classify mental disorders have been of tremendous value to Psychiatry, there is growing pressure to reform psychiatric diagnosis. In other areas in medicine staging and profiling has been a fruitful strategy to model the diagnosis of complex disorders.

AIM

To examine whether staging and profiling may be a fruitful model for the diagnosis of psychiatric disorders.

RESULTS

Clinical staging and profiling may help to reform our current static, descriptive and largely categorical classification of mental disorders and arrive at a diagnostic system that is developmental, that can accommodate better the continuous nature of most mental health problems and that is sensitive to etiologic and prognostic risk factors.

CONCLUSION

Looking beyond the forthcoming revisions of DSM and ICD, clinical staging and profiling provide the necessary framework for a more fundamental reform of psychiatric diagnosis.

[Behavioural standard or coercive measure? Some considerations regarding the special issue on ROM]

BACKGROUND

The cost of mental health care has possibly risen more than costs in other sectors of health care in the Netherlands. In an attempt to control the rising costs, new policies have been implemented that include the introduction of selective financial penalties for those in need of mental health care as well as the start of performance-based mental health care reimbursement. In order to achieve the latter goal, a nation-wide large-scale data collection was introduced based on clinical routine outcome monitoring (ROM) data, with a view to using these data for benchmarking.

AIM

Closer inspection of the benchmarking efforts in terms of scientific validity.

METHOD

Qualitative review and analysis.

RESULTS

Analysis shows that the type of ROM data that is collected in the Netherlands is valid for tracking the outcomes of individual patients, but unsuitable for performance comparisons between institutions for reasons of case-mix, instrument-mix, bias and lack of sensitivity.

CONCLUSION

Attempts to introduce benchmarking based on rom will probably have a negative impact on the practice of mental health care in the Netherlands. More input from mental health professionals and scientists is required in order to identify more rational and efficient ways of spending scarce resources.

Replication in two independent population-based samples that childhood maltreatment and cannabis use synergistically impact on psychosis risk

BACKGROUND

There may be biological plausibility to the notion that cannabis use and childhood trauma or maltreatment synergistically increase the risk for later development of psychotic symptoms. To replicate and further investigate this issue, prospective data from two independent population-based studies, the Greek National Perinatal Study (n=1636) and The Netherlands Mental Health Survey and Incidence Study (NEMESIS) (n=4842), were analyzed.

METHOD

Two different data sets on cannabis use and childhood maltreatment were used. In a large Greek population-based cohort study, data on cannabis use at age 19 years and childhood maltreatment at 7 years were assessed. In addition, psychotic symptoms were assessed using the Community Assessment of Psychic Experiences (CAPE). In NEMESIS, the Composite International Diagnostic Interview (CIDI) was used to assess psychotic symptoms at three different time points along with childhood maltreatment and lifetime cannabis use.

RESULTS

A significant adjusted interaction between childhood maltreatment and later cannabis use was evident in both samples, indicating that the psychosis-inducing effects of cannabis were stronger in individuals exposed to earlier sexual or physical mistreatment [Greek National Perinatal Study: test for interaction F(2, 1627)=4.18, p=0.02; NEMESIS: test for interaction χ2(3)=8.08, p=0.04].

CONCLUSIONS

Cross-sensitivity between childhood maltreatment and cannabis use may exist in pathways that shape the risk for expression of positive psychotic symptoms.