Cannabis use and genetic predisposition for schizophrenia: a case-control study

BACKGROUND

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

METHOD

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

RESULTS

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

CONCLUSIONS

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

Subtle gene-environment interactions driving paranoia in daily life

It has been suggested that genes impact on the degree to which minor daily stressors cause variation in the intensity of subtle paranoid experiences. The objective of the present study was to test the hypothesis that catechol-O-methyltransferase (COMT) Val(158)Met and brain-derived neurotrophic factor (BDNF) Val(66)Met in part mediate genetic effects on paranoid reactivity to minor stressors. In a general population sample of 579 young adult female twins, on the one hand, appraisals of (1) event-related stress and (2) social stress and, on the other hand, feelings of paranoia in the flow of daily life were assessed using momentary assessment technology for five consecutive days. Multilevel regression analyses were used to examine moderation of daily life stress-induced paranoia by COMT Val(158)Met and BDNF Val(66)Met genotypes. Catechol-O-methyltransferase Val carriers displayed more feelings of paranoia in response to event stress compared with Met carriers. Brain-derived neurotrophic factor Met carriers showed more social-stress-induced paranoia than individuals with the Val/Val genotype. Thus, paranoia in the flow of daily life may be the result of gene-environment interactions that can be traced to different types of stress being moderated by different types of genetic variation.

Meta-analyses of cognitive functioning in euthymic bipolar patients and their first-degree relatives

BACKGROUND

Previous work suggests that impairments in executive function and verbal memory in particular may persist in euthymic bipolar patients and serve as an indicator of genetic risk (endophenotype).

METHOD

A systematic review of the literature was undertaken. Effects sizes were extracted from selected papers and pooled using meta-analytical techniques.

RESULTS

In bipolar patients, large effect sizes (d>0.8) were noted for executive functions (working memory, executive control, fluency) and verbal memory. Medium effect sizes (0.5<d<0.8) were reported for aspects of executive function (concept shifting, executive control), mental speed, visual memory, and sustained attention. Small effect sizes (d<0.5) were found for visuoperception. In first-degree relatives, effect sizes were small (d<0.5), but significantly different from healthy controls for executive function and verbal memory in particular.

CONCLUSIONS

Executive function and verbal memory are candidate bipolar endophenotypes given large deficits in these domains in bipolar patients and small, but intermediate, cognitive impairments in first-degree relatives.

Mental health care use in Parkinson's disease: a record linkage study

BACKGROUND/AIM

Parkinson's disease (PD) is often complicated by psychiatric comorbidity, which is likely to lead to a higher use of mental health care facilities. In addition, psychiatric symptomatology and associated mental health care use may be present even before motor symptoms and PD are diagnosed, as the pathophysiology of PD and its psychiatric consequences are likely to overlap to a degree. This will be reflected in an increasing mental health care use prior to the diagnosis of PD. The aim of this study is to compare the level of mental health care use of PD patients with that of a matched control population, and to assess possible fluctuations in mental health care use in the years surrounding the diagnosis of PD.

METHODS

Record linkage study comparing the number of mental health care contacts by PD patients with that of a matched control population.

RESULTS

Mental health care use by PD patients already increased before the time of diagnosis of PD, and decreased again after diagnosis. The relative risk for mental health care use was increased from 3 years prior (RR 1.41; 95% CI 1.27-1.57) to 2 years after (RR 1.83; 95% CI 1.63-2.05) diagnosing PD. This increase was higher for women than for men, and higher for younger than older individuals.

CONCLUSION

The early pathophysiology of PD is expressed in part as mental health problems, suggesting the possibility of early detection in particular demographic groups and a proactive approach to early intervention for comorbid psychopathology.

[Long-term service-dependent patients in mental health care: connection to urbanisation]

BACKGROUND

In view of the increased rate of psychiatric morbidity in urban areas there is likely to be a relation between urbanisation and the extent to which patients use the care services. It is not yet known whether this relation is particularly strong in the case of long-term service-dependent patients with mental health problems.

AIM

To investigate the possible relation between the prevalence of long-term service-dependent patients and the degree of urbanisation and to find out if there are differences in the strength of this relation in the case of different types of long-term patients and between these patients and other psychiatric patients.

METHOD

Data were collected from three psychiatric case registers and from the Statistics Netherlands (cbs). Distinctions were made between three types of long-term patients: 'long stay', 'residential & outpatient' and 'outpatient'. The population was divided into five categories according to the degree of urbanisation in the area of residence. Data were analysed using Poisson regression analysis, corrected for differences in age, sex, marital status and the amount of care available.

RESULTS

The incidence rate ratios for the categories 'long stay', 'residential & outpatient' and 'outpatient' and for other patients were significantly higher for each category of urbanisation than for non-urbanised municipalities. There was also a significant positive linear relation. For long stay patients no significant relation was found with the degree of urbanisation. The total ratios for long-term patients were higher than the ratios for other types of patients. The ratios for residential and outpatient were higher than the ratios for outpatient.

CONCLUSION

The prevalence of long-term service-dependent patients in mental health care increases with the degree of urbanisation and this increase is stronger than the increase observed for other patients. Furthermore, the relation with urbanisation for the category residential and outpatient is stronger for the category residential and outpatient than for the long-term outpatients.

[An observational study of 'assertive outreach' with remission as outcome measure]

BACKGROUND

Systems of intensive care such as the Function Assertive Community Treatment (Function-act) are advocated because they are reported to have achieved very promising results. However, comparative studies aimed at measuring the efficacy of such systems are mainly of short duration and the outcome measure is nearly always the amount of care provided.

AIM

To investigate, via an observational study, changes that occurred in the number of patients going into remission and in the amount of care provided before and after the introduction of f-act.

METHOD

f-act was introduced in Maastricht and the surrounding area (population 220,000) at the beginning of 2002. Cumulative routine measurements of the effect of care in the region had been performed since 1998. These measurements were used to compare the proportion of patients in remission in two non-overlapping patients cohorts, each covering a 4-year period, namely 1998-2001 and 2002-2005. results The proportion of patients who made the transition to remission increased from 19% in the period before the introduction of f-act to 31% in the period after its introduction (or = 2.21; 95% ci: 1.03-4.78), but after controlling for confounders the difference was no longer statistically significant.

CONCLUSION

In routine clinical practice f-act can reduce the intensity of psychopathological symptoms, possibly because the care provided under f-act is less fragmented. However, more research is needed before the claimed beneficial effects of f-act can be proved conclusively.

[A psychosis proneness-persistence-impairment model of psychotic disorders]

There is evidence that the normally transitory developmental expression of psychosis (psychosisproneness) may first of all become abnormally persistent (persistence) and later on become clinically relevant (impairment), depending on the amount of environmental risk to which the person is exposed. According to the psychosis-proneness-persistence impairment model, genetic background factors can impact on a transitory expression of psychosis. Whether or not this will lead to a poor prognosis in terms of persistence and clinical need will depend on the interaction between environmental exposure and genetic risk.

Cognitive alterations in groups at risk for psychosis: neutral markers of genetic risk or indicators of social disability?

OBJECTIVE

To investigate whether cognitive alterations associated with vulnerability to psychosis, are associated with expression of psychopathology and functional outcome in groups at different levels of risk for psychotic illness.

METHOD

Neurocognition, psychopathology and functional outcome were measured in subjects with variable risk for psychosis: i) 29 patients with psychotic disorder, ii) 46 subjects at familial risk, iii) 41 subjects at psychometric risk and iv) 54 control subjects.

RESULTS

Dose-response relationships between cognitive dysfunction and increasing risk for psychosis were found. Cognitive alterations were predicted by negative symptoms in patients and by positive psychotic experiences in the familial risk group. In both at risk groups, cognitive speed was associated with functional outcome.

CONCLUSION

Some cognitive impairments serve as neutral endophenotypic marker across the psychosis continuum. However, other cognitive alterations associated with transmission of psychosis may have a direct impact on the pathway from risk to psychopathology and alterations in functioning.

The association between cognition and functional outcome in first-episode patients with schizophrenia: mystery resolved?

OBJECTIVE

The presence of a prospective association between cognition and functional outcome in first episode patients with schizophrenia is much debated.

METHOD

Associations between Intelligence Quotient (IQ) measures and functional outcome were assessed at the first hospitalization and after 10 years follow-up.

RESULTS

Functional outcome was associated with estimated premorbid IQ and IQ at 10-year follow-up, but not with IQ assessed at first hospitalization.

CONCLUSION

The presence of a prospective as well as a cross-sectional relationship of the global cognitive measure IQ with 10-year functional outcome could be established. However, assessing associations between cognitive measures assessed at first hospitalization and subsequent functional outcome, can give inconclusive results due to non-uniform intellectual deterioration from premorbid level in the period preceding the first hospitalization.

The dynamics of symptomatic and non-symptomatic coping with psychotic symptoms in the flow of daily life

OBJECTIVE

Previous research has suggested that going along with psychotic symptoms (symptomatic coping) is less effective than other coping strategies with psychotic symptoms. This pilot study aims to validate such findings using a momentary assessment strategy of coping with stress in daily life.

METHOD

Patients with psychosis (n = 35) were studied with the Experience Sampling Method (ESM; a structured diary technique) to assess coping with stress in daily life. This was analysed in relation to coping with psychotic symptoms using a previously validated interview (Maastricht Assessment of Coping Strategies).

RESULTS

Symptomatic and non-symptomatic coping were negatively associated with each other. Symptomatic coping was negatively associated with the level of coping in daily life, whereas a positive association was apparent for non-symptomatic coping. Non-symptomatic coping, but not symptomatic coping, predicted appraisals of distress associated with psychotic symptoms.

CONCLUSION

Effective coping may be associated with the tendency to develop conscious appraisals of distress associated with psychotic symptoms.

Subclinical psychotic experiences and cognitive functioning as a bivariate phenotype for genetic studies in the general population

OBJECTIVE

Cognitive deficits may be vulnerability markers for the development of schizophrenia. This study examined whether cognitive deficits are related to specific dimensions of subclinical psychotic experiences and whether associations between these variables are caused by additive genetic, common environmental and/or individual-specific environmental factors.

METHOD

A general population sample of 298 female twin pairs completed the Community Assessment of Psychic Experiences and a neuropsychological test battery. Associations between subclinical positive and negative psychotic dimensions and neuropsychological factors (episodic memory and information processing speed) were examined. Univariate correlation and structural equation analyses were performed to explore the role of genetic and environmental factors in the phenotypes separately. Bivariate correlation and structural equation analyses were applied to examine the causes of association.

RESULTS

There were significant correlations between information processing speed and both the positive (r=.11; p<.05) and the negative dimension (r=.10; p<.05). For the negative dimension and for speed of processing, the data suggested a model that included genetic factors. The observed phenotypic correlation between the negative dimension and information processing speed could be solely explained in terms of additive genetic factors. Although the comparison of the correlations for MZ and DZ pairs did not give a clear indication as to the underlying causes of the association, structural equation modelling suggested that the observed phenotypic correlation between the negative dimension and information processing speed could be solely explained in terms of additive genetic factors.

CONCLUSION

Negative symptoms and information processing speed are associated at the subclinical level and this association appears to be influenced by genetic factors exclusively. Bivariate psychosis phenotypes may represent suitable candidates for molecular genetic studies in the general population.

[Can the "Camberwell Assessment of Need" predict changes in care consumption?]

BACKGROUND

Because of the shift in the Dutch psychiatric care system towards care based on actual need, we should have some kind of instrument for assessing the future need for care. The Camberwell Assessment of Need (CAN) is such an instrument. It is particularly useful when there is a clear link between the need for care and the consumption of care.

AIM

To study whether the can is a predictor of (changes in) care consumption.

METHOD

The Maastricht Cumulative Needs for Care Monitor (CNCM) involves an interview with all patients with psychotic disorders who are in care in the Maastricht region. The interview takes place at intake and thereafter annually. The main instrument of the CNCM is the CAN, but other instruments are also included. CNCM data are matched with care consumption data extracted from the Psychiatric Case Register South Limburg, including both care consumption in the year before and in the year after the CNCM assessment.

RESULTS

Patients with intermediate or higher levels of need for care were found to use more inpatient care than patients with lower levels of need for care. In addition, the results showed that a high level of need for care was a predictor of shifts from low inpatient care consumption to high inpatient care consumption, although statistically imprecise by conventional alpha.

CONCLUSION

The CAN may well be a valuable instrument for assessing future inpatient care consumption.

Relationship between DHA status at birth and child problem behaviour at 7 years of age

Animal studies have demonstrated behavioural effects of long-chain polyunsaturated fatty acid (LC-PUFA) deficiencies and in humans, several psychiatric disorders have been linked to abnormal essential fatty acid metabolism. The aim of this study was to examine the relationship between LC-PUFA status at birth and the later development of problem behaviour. In a sample of 393 children, higher levels of docosahexaenoic acid (DHA) at birth were associated with lower levels of internalising problem behaviour at age 7 years. The association was markedly present in the infants fed with artificial formula (n=215, Beta=-0.32, P=0.000), but absent in the infants fed with human milk (n=170, Beta=0.11, P=0.325). The associations between arachidonic acid and internalising or externalising behaviour were neither large nor significant. The results suggest that perinatal DHA status may have long-term behavioural consequences. Therefore, we suggest to include measures of problem behaviour in future trials of LC-PUFA supplementation of mothers and/or infants.

[Coping matters in psychosis. Coping and the need for professional care in cases of subclinical psychosis]

BACKGROUND

Changes in the amount of care required in cases of subclinical psychosis are examined in relation to (1) the level of patient distress and (2) the level of dysfunctional coping.

METHOD

The Netherlands Mental Health Survey and Incidence Study (nemesis) is a longitudinal investigation into the occurrence of psychopathology in the general population. In the first two measurements of the nemesis study 4722 individuals had not been diagnosed as having a psychotic disorder according to dsm-iii-r. In the third measurement, 83 of those 4.722 were found to have had at least one subclinical psychotic experience. A panel of experts decided on the level of care that patients required. results Of the various types of psychotic experiences it was only 'passivity phenomena', hearing voices' and 'non-verbal hallucinations' which were associated with the need for care. These associations were largely explained by distress associated with the psychotic experience, with the exception of hearing voices. There were qualitative differences between the various types of coping: in particular, 'symptomatic coping' with psychotic experiences was associated with less perceived control over the psychotic experience (or = 0,79; 95% CI (confidence interval) 0,63-0,98) and an increased probability of the need for care (or = 6,07; 95% CI 1,95-18,95).

CONCLUSION

Various types of psychotic experiences require different levels of care. The need for care can arise when psychotic experiences begin to cause patient distress and/or dysfunctional coping. These factors may well play a role in turning an individual with subclinical psychotic experiences into a psychiatric patient.

[Remission criteria in schizophrenia]

BACKGROUND

Recent research shows that there is a considerable variation in the incidence and course of schizophrenia. The illness therefore can best be defined in terms of changeability and plasticity.

AIM

An internationally accepted standard definition of symptomatic remission.

METHOD

Two international panels of experts have wrestled with the problem of whether or how symptomatic remission in persons diagnosed with schizophrenia can be defined. A draft definition was published recently.

RESULTS

The proposed definition is conceptually viable and can be incorporated easily into both clinical practice and clinical research. Acceptance of the remission concept can raise expectations about treatment outcome to a higher level than is possible when a patient is merely defined as being 'stable', can improve the quality of treatment documentation and facilitate the dialogue concerning treatment expectations. The availability of validated outcome measures based on remission should enhance the reporting and the comparability of clinical research and should facilitate the design and interpretation of new research into the relation between symptomatic remission and functional outcomes.

CONCLUSION

The introduction of standard remission criteria can create many opportunities for clinical practice, clinical research and cumulative records of results; at the same time it can facilitate a dialogue with patients and help to clarify the diagnosis of schizophrenia.

Trends in cannabis use prior to first presentation with schizophrenia, in South-East London between 1965 and 1999

BACKGROUND

There is evidence that cannabis use might be relevant to the aetiology of schizophrenia. We aimed to measure any change in cannabis use over time in those first presenting with schizophrenia in South-East London from 1965 to 1999, and compare this with change in use in those presenting with non-psychotic psychiatric disorders.

METHOD

The rate of cannabis use in the year prior to first ever presentation was measured over seven time periods. Logistic regression modelling was used to determine (a) whether cannabis use changed over time, after controlling for age, sex and ethnicity, and (b) whether there was an interaction between diagnosis and time.

RESULTS

Cannabis use increased over time in both the schizophrenia group [odds ratio per time period (OR) 2.03, 95% confidence interval (CI) 1.74-2.38, p<0.0001] and the non-psychotic disorders group (OR 1.24, 95% CI 1.05-1.47, p=0.012), after controlling for age, sex and ethnicity. However, the effect of time was significantly greater in the schizophrenia group than in the non-schizophrenia group (chi2=17, p<0.0001).

CONCLUSION

Cannabis use in the year prior to presentation with schizophrenia increased markedly between 1965 and 1999, and disproportionately so compared to increase in cannabis use in other psychiatric disorders.

A momentary assessment study of the relationship between affective and adrenocortical stress responses in daily life

The tendency to experience negative emotions in the face of stress may lead to repeated overactivation of the hypothalamic-pituitary-adrenal axis. In a sample of 556 women, this study used the Experience Sampling Method to assess different daily stressors, current mood, and salivary cortisol, 10 times daily for 5 days. Multilevel analyses estimated the contributions of stressors and mood states as predictors of salivary cortisol secretion. Results showed that minor stressors were associated with decreased positive affect and increased negative affect, agitation, and cortisol. Of the mood states, only negative affect was independently associated with cortisol. Negative affect also mediated effects of daily stressors on cortisol. Although further research is needed to clarify: (i) the causal pathways between daily stress, mood, and cortisol and (ii) the importance of daily stress reactivity as a prospective risk factor, these findings confirm that minor daily stressors can influence emotional and biological processes involved in subjective well-being.

Validity and reliability of the CAPE: a self-report instrument for the measurement of psychotic experiences in the general population

OBJECTIVE

General population longitudinal cohort studies have demonstrated the prognostic validity of self-reported psychotic experiences, but data on reliability and cross-validation with interview-based measures of these experiences are sparse. This study tested the reliability and validity of the Community Assessment of Psychic Experiences (CAPE42).

METHOD

At baseline, the CAPE42 was used to measure the subclinical psychosis phenotype in a general population sample (n = 765). At follow-up (mean interval: 7.7 months), the Structured Interview for Schizotypy, Revised (SIS-R), the Brief Psychiatric Rating Scale (BPRS), and the CAPE42 were administered (n = 510).

RESULTS

Baseline self-reported dimensions of psychosis were specifically and independently associated with their equivalent interview-based dimension at follow-up (standardized effect sizes of 0.4-0.5) and with their equivalent self-reported measure (standardized effect sizes of 0.6-0.8).

CONCLUSION

The results indicate that self-reported dimensions of psychotic experiences in general population samples appear to be stable, reliable and valid.

Attribution style and psychosis: evidence for an externalizing bias in patients but not in individuals at high risk

BACKGROUND

The aims of the study were to investigate whether (i) patients with lifetime presence of non-affective psychosis show an external-personal attribution bias for negative events, (ii) this attribution style can also be detected in first-degree relatives of patients with psychosis and subjects with subclinical psychotic experiences, and (iii) this attribution style is related to the presence of psychotic symptoms, in particular delusions.

METHOD

Participants were 23 patients with lifetime presence of non-affective psychosis, a high- risk group of 36 first-degree relatives of patients with non-affective psychosis, a high-risk group of 31 subjects with subclinical psychotic experiences and 46 normal controls. Attribution style was measured by the Internal, Personal and Situational Attribution Questionnaire. Positive symptoms were assessed with the Present State Examination (PSE) and the Scale for the Assessment of Positive Symptoms (SAPS).

RESULTS

Relative to the controls, an externalizing bias was apparent in the patient group (beta = 0.20, p = 0.03) but not in the two high-risk groups. There was a dose-response association between externalizing bias and the delusions subscale of the PSE (relative to lowest level: highest level of delusions: beta = 0.53, p = 0.04; intermediate levels of delusions: beta = 0.23, p = 0.35). No significant differences were found in personalizing bias between the four groups.

CONCLUSIONS

Patients with psychosis tend to use an externalizing bias in their explanations of negative social events, and this bias is associated with the presence of positive psychotic symptoms, in particular delusions. A deviant attribution style is not part of the vulnerability to psychosis.

A prospective study of the transition rates of subthreshold (hypo)mania and depression in the general population

BACKGROUND

Previous work suggests that subthreshold depression and subthreshold (hypo)mania are common, although little is known about the prognosis in terms of transition to clinical disorder. This paper presents data on the temporal relationship between subthreshold and clinical expression of mood phenotypes.

METHOD

In a random general population sample of 7076 individuals, symptoms of depression and (hypo)mania were measured with the Composite International Diagnostic Interview (CIDI) at baseline, after 1 year, and 2 years later.

RESULTS

At baseline, the lifetime prevalences of depressive and (hypo)manic symptoms were 17.2% and 1.2% respectively. Predictive values of mood symptoms for a DSM-III-R mood disorder ranged from 14.3% to 50%. (Hypo)manic mood symptoms had much higher predictive values than unipolar manifestations, not only for bipolar disorder but also for major depression.

CONCLUSIONS

The subthreshold expressions of depression and (hypo)mania are prevalent and continuous with more severe clinical states. The cross-prediction of mood symptoms may support a continuum from depressive to (hypo)manic symptoms. The high predictive value of (hypo)manic symptoms for mood disorders suggests that the experience of (hypo)manic symptoms is a stronger indicator of vulnerability for mood dysregulation than the experience of depressive symptoms.

Standardized remission criteria in schizophrenia

OBJECTIVE

Recent work has focussed on schizophrenia as a 'deficit' state but little attention has been paid to defining illness plasticity in terms of symptomatic remission.

METHOD

A qualitative review of a recently proposed concept of remission [N.C. Andreasen, W.T. Carpenter Jr, J.M. Kane, R.A. Lasser, S.R. Marder, D.R. Weinberger (2005) Am J Psychiatry 162: 441] is presented.

RESULTS

The proposed definition of remission is conceptually viable, and can be easily implemented in clinical trials and clinical practice. Its increasing acceptance may reset expectations of treatment to a higher level, improve documentation of clinical status and facilitate dialogue on treatment expectations. The availability of validated outcome measures based on remission will enhance the conduct and reporting of clinical investigations, and could facilitate the design and interpretation of new studies on cognition and functional outcomes. While useful as a concept, it is important to consider that remission is distinct from recovery.

CONCLUSION

The introduction of standardized remission criteria may offer significant opportunities for clinical practice, health services research and clinical trials.

Evidence for three distinct classes of 'typical', 'psychotic' and 'dual' mania: results from the EMBLEM study

OBJECTIVE

To describe patients included in the European Mania in Bipolar Longitudinal Evaluation of Medication (EMBLEM) study and to assess and clinically validate the presence of clinical subtypes of patients with acute mania.

METHOD

The EMBLEM study is a 2-year prospective, observational study on the treatment and outcome of patients who are treated for a manic or mixed episode. Latent Class Analysis was used to define discrete groups of patients at baseline.

RESULTS

Three groups were identified: 'typical mania' (59% of patients); 'psychotic mania' (27%) with more severe mania and presence of psychotic symptoms; and 'dual mania' (13%) with a high proportion of substance abuse. Patient groups differed in age of onset, social functioning and service needs.

CONCLUSION

Dual mania represents a distinct and not infrequent subgroup of patients with mania. The exclusion of patients with comorbid substance problems from clinical trials creates a gap in our knowledge on treatment effectiveness.

The combination of shared family environment and individual-specific developmental deviance as a cause for treated psychiatric morbidity in children

OBJECTIVE

There is an incomplete understanding of why some children growing up in the same family are in need of treatment for psychiatric morbidity whilst their siblings are not. The present paper examined the possible role of individual-specific developmental risk factors.

METHOD

Three case-control analyses were conducted: i) 80 children referred to the Community Mental Health Centre (cases) and 320 population controls, ii) 68 healthy siblings of cases and 272 population controls, and iii) 80 children and 68 healthy siblings. Measures of development and psychosocial circumstances were obtained from routine, longitudinal, standardized child medical records.

RESULTS

Given shared family environments, additional presence of delays in speech and motor development contributed most to differential sibling mental health outcomes. In addition, cases displayed both earlier expression and more severe levels of developmental behavioural deviance than their healthy siblings, who in turn had higher levels of behavioural deviance than population controls.

CONCLUSION

In siblings sharing a familial risk environment, development of psychiatric morbidity may be canalized through additional individual-specific developmental exposures.

Are apparent associations between parental representations and psychosis risk mediated by early trauma?

OBJECTIVE

It was investigated whether the reported association between representations of parental rearing style and psychosis does not represent a main effect, but instead is a proxy indicator of the true underlying risk factor of early trauma.

METHOD

In a general population sample of 4045 individuals aged 18-64 years, first ever onset of positive psychotic symptoms at 3-year follow-up was assessed using the Composite International Diagnostic Interview and clinical interviews if indicated. Representations of parental rearing style were measured with the Parental Bonding Instrument (PBI).

RESULTS

Lower baseline level of PBI parental care predicted onset of psychotic symptoms 2 years later. However, when trauma was included in the equation, a strong main effect of trauma emerged at the expense of the effect size of PBI low care.

CONCLUSION

The results suggest that associations between representations of parental rearing style and psychosis may be an indicator of the effect of earlier exposure to childhood trauma.

Childhood trauma, psychosis and schizophrenia: a literature review with theoretical and clinical implications

OBJECTIVE

To review the research addressing the relationship of childhood trauma to psychosis and schizophrenia, and to discuss the theoretical and clinical implications.

METHOD

Relevant studies and previous review papers were identified via computer literature searches.

RESULTS

Symptoms considered indicative of psychosis and schizophrenia, particularly hallucinations, are at least as strongly related to childhood abuse and neglect as many other mental health problems. Recent large-scale general population studies indicate the relationship is a causal one, with a dose-effect.

CONCLUSION

Several psychological and biological mechanisms by which childhood trauma increases risk for psychosis merit attention. Integration of these different levels of analysis may stimulate a more genuinely integrated bio-psycho-social model of psychosis than currently prevails. Clinical implications include the need for staff training in asking about abuse and the need to offer appropriate psychosocial treatments to patients who have been abused or neglected as children. Prevention issues are also identified.

Deconstructing the familiality of the emotive component of psychotic experiences in the general population

OBJECTIVE

Genetic and environmental influences on variation in distress associated with subclinical psychotic experiences were examined.

METHOD

A total of 289 twin pairs filled in the Community Assessment of Psychic Experiences, a self-report instrument assessing subclinical positive and negative psychotic experiences and associated distress (distresspos and distressneg). Using structural equation modelling, univariate and bivariate models were fitted.

RESULTS

Univariate model fitting showed genetic and non-shared environmental influences on both distresspos and distressneg. Bivariate model fitting showed that 52% of the correlation between the two phenotypes (r=0.46) was because of shared genes and that non-shared environmental factors accounted for 48% of the correlation.

CONCLUSION

Liability to psychosis not only refers to the development of psychosis per se, but also to the liability to develop dysfunctional emotional appraisals. The emotive component of psychosis liability involves genetic transmission of a general, non-symptom-specific distress factor that may be a target for molecular genetic research.

Early trauma may increase the risk for psychotic experiences by impacting on emotional response and perception of control

OBJECTIVE

Exposure to early trauma may increase the risk of dysfunctional responses to anomalous psychotic experiences resulting in psychotic symptom formation.

METHOD

In a three-wave longitudinal general population study, 4045 never-psychotic individuals exposed and non-exposed to trauma before the age of 16 years, according to baseline interview were interviewed for the onset of psychotic experiences 3 years later (T2). In 36 individuals with incident psychosis at T2, assessments were made, for each psychotic experience, of i) the amount of distress associated with and ii) the degree of coping and subjective control over the experience.

RESULTS

In the 16 observations of an incident psychotic experience, in the absence of distress, the baseline rate of early trauma was low (6%), whereas it was much higher in the 21 observations of an incident psychotic experience with distress [43%; odds ratio=10.0, 95% confidence interval (CI): 1.04, 96.3; P=0.046]. Similarly, coping attempts in the context of early trauma was associated with less control (reduction of 2 points on a seven-point scale, 95% CI: -4.0, -0.07).

CONCLUSION

Early experience of trauma may create lasting cognitive and affective vulnerabilities to develop clinical symptoms arising out of early, non-clinical psychotic experiences.

Effects of epoetin alfa on blood transfusions and postoperative recovery in orthopaedic surgery: the European Epoetin Alfa Surgery Trial (EEST)

BACKGROUND AND OBJECTIVE

Preoperative epoetin alfa administration decreases transfusion requirements and may reduce transfusion complications, such as postoperative infection due to immune suppression and thus hospitalization time. This study examined the impact of preoperative epoetin alfa administration on postoperative recovery and infection rate.

METHODS

In an open randomized controlled multicentre trial in patients undergoing orthopaedic surgery, the effects of preoperative administration of epoetin alfa vs. routine care were compared in six countries. Haemoglobin (Hb) values, transfusions, time to ambulation, time to discharge, infections and safety were evaluated in patients with preoperative Hb concentrations 10-13g dL(-1) (on-treatment population: epoetin n = 460; control n = 235), from study entry until 4-6 weeks after surgery. Outcome was also compared in patients with and without transfusion.

RESULTS

Epoetin-treated patients had higher Hb values from the day of surgery until discharge (P < 0.001) and lower transfusion rates (12% vs. 46%; P < 0.001). Epoetin treatment delivered no significant effect on postoperative recovery (time to ambulation, time to discharge and infection rate). However, the time to ambulation (3.8+/-4.0 vs. 3.1+/-2.2days; P < 0.001)and the time to discharge (12.9+/-6.4 vs. 10.2+/-5.0 days; P < 0.001) was longer in the transfused than in the non-transfused patients. Side-effects in both groups were comparable.

CONCLUSIONS

Epoetin alfa increases perioperative Hb concentration in mild-to-moderately anaemic patients and thus reduces transfusion requirements. Patients receiving blood transfusions require a longer hospitalization than non-transfused patients.

Behavioural sensitization to daily life stress in psychosis

BACKGROUND

Recent neurobiological models provide a possible mechanism of daily life stress directly affecting the intensity of psychotic experiences in vulnerable individuals. In order to validate such a mechanism, the impact of daily life stress on psychosis intensity was investigated in two groups at increased risk of onset (relatives) and relapse (patients) of psychosis.

METHOD

Patients with psychosis in a clinical state of remission (n = 42), first-degree relatives (n = 47), and control subjects (n = 49) were studied with the Experiencing Sampling Method (ESM is a structured diary technique assessing current context and psychopathology in daily life) to assess (1) appraised subjective stress related to daily activities and events, and (2) intensity of subtle psychotic experiences in daily life.

RESULTS

Multilevel regression analyses revealed significant increases in psychosis intensity associated with increases in subjective activity--and event-related stress in patients. First-degree relatives reported increases in psychosis intensity in relation to activity-related stress but not event-related stress. No association was found in control subjects.

CONCLUSIONS

Subjects at increased risk for psychosis show continuous variation in the intensity of subtle psychotic experiences associated with minor stresses in the flow of daily life. Behavioural sensitization to environmental stress may therefore be a vulnerability marker for schizophrenia, reflecting dopaminergic hyper-responsivity in response to environmental stimuli.

Electronic monitoring of salivary cortisol sampling compliance in daily life

Naturalistic research methods have been developed to collect data in the daily environment, providing ecological valid measures. Recent reports suggest, however, that compliance with fixed time sampling protocols may be problematic and can bias results. This study investigated compliance with an intensive, random time sampling protocol for salivary cortisol and effects of non-compliance on cortisol results. Twenty female twin pairs and nineteen of their sisters were instructed to take saliva samples when signaled at ten unpredictable moments on each of five consecutive days. Subjects recorded collection times, unaware that compliance with the sampling protocol was being investigated by means of electronic monitoring devices. Samples taken < or = 15 min after the signal, according to self-report, were defined as adherent to the protocol. Samples taken < or = 10 min after the self-reported collection time, according to the monitor, were defined as accurate. Self-reported adherence to the sampling protocol was 96.4%. Verified compliance was somewhat lower, with 81% of all saliva samples accurately timed. Contrary to previous reports, inclusion of non-compliant samples in the analysis did not distort the cortisol diurnal profile. Intensive, random time sampling appears to have advantages over fixed time sampling for obtaining valid cortisol profiles when researchers do not have devices to monitor compliance. Results indirectly support the validity of momentary self-report data about daily experiences obtained with the same sampling methods.

Ethnic differences in first clinical presentation of bipolar disorder: results from an epidemiological study

BACKGROUND

Although high incidence rates of mania have been described in some ethnic minority populations, little is known about any ethnic differences in the early clinical presentation of bipolar disorder.

METHODS

All cases of operationalised DSM-IV bipolar I disorder (BPI), first manic episode, within a defined epidemiological catchment area over a 35-year period, were identified; sociodemographic data, including ethnicity, and clinical information were then extracted. The proportion of African-Caribbean (n=52), African (n=33) and white European (n=149) cases who experienced a depressive episode before onset of mania and psychotic symptoms at first mania were compared.

RESULTS

African-Caribbean and African groups were significantly less likely to have experienced a depressive episode before onset of first mania, at 13.5% and 6.1%, respectively, compared with 28.1% in the white European group. African-Caribbean and African groups also experienced more severe psychotic symptoms at first mania, but there were no differences in mood incongruent or first rank symptoms between ethnic groups.

LIMITATIONS

Data pertaining to diagnosis and clinical symptoms were extracted by retrospective case note review.

CONCLUSIONS

Ethnic differences in clinical presentation of bipolar disorder may have implications for assessment and treatment of ethnic minority patients.

Early maternal stress and health behaviours and offspring expression of psychosis in adolescence

OBJECTIVE

It has been suggested that influences operating early in life may affect the risk of postpubertal psychosis outcomes. This hypothesis was tested using a broad outcome of psychotic symptoms expressed in adolescence (prevalence: 15.6%).

METHOD

Findings are based on a longitudinal, population-based cohort study of 963 adolescents aged 15-20 years and their parents in the area of Munich, Germany. Trained psychologists assessed adolescents with the Munich-Composite International Diagnostic Interview. Independently, direct diagnostic interviews were conducted with the parents.

RESULTS

A range of medical complications of pregnancy and delivery, including lower birth weight, were not associated with the psychosis outcome. However, a number of maternal health behaviours and experiences did show associations, independent of confounders.

CONCLUSION

Not maternally reported medical complications of pregnancy and delivery, but maternal prenatal health behaviours predicted expression of psychosis along a continuum in adolescence. This effect may either be direct or constitute a proxy for later postnatal maternal behaviours associated with psychosis risk in the offspring.

Hallucinatory experiences and onset of psychotic disorder: evidence that the risk is mediated by delusion formation

OBJECTIVE

To examine the hypothesis that the risk for onset of psychotic disorder in individuals with self-reported hallucinatory experiences (HE) would be higher in those who developed delusional ideation (DE) than in those who did not.

METHOD

A population sample of 4673 individuals were interviewed with the Composite International Diagnostic Interview at baseline and 1 and 3 years later. At year 3, clinical re-interview took place to identify onset of psychotic disorder.

RESULTS

Given the presence of HEs at baseline, the increase in risk of having the psychosis outcome at year 3 was much higher in those with DE at year 1 than in those without DE (risk difference between individuals with and without DE: 18.72%, 95% CI: 2.22-35.23, chi(2) = 4.94, df = 1, P = 0.026).

CONCLUSION

The results are in line with current psychological theories stating that clinical outcome of psychosis-like experiences is related to the development of secondary beliefs and appraisals.

Pleasurable auditory hallucinations

OBJECTIVE

The focus in auditory hallucination (AH) research is usually on the negative impact of the experience itself. There are practically no studies on whether voices can be perceived as pleasurable. The aim of the present study was to assess the frequency of voices as a pleasurable experience in a psychotic patient population.

METHOD

A total of 160 patients with AHs (89 schizophrenia and 17 other psychoses) were assessed with the psychotic symptom rating scale (PSYRATS) for AHs, including an added item on whether the experience was pleasurable.

RESULTS

Twenty-eight patients (26%) reported the voices as a pleasurable experience and 10 of them did so frequently. Pleasurable hallucinations showed negative associations with amount and intensity of distress, degree of negative content and loudness. Positive associations were apparent with chronicity and perceived control over the voices.

CONCLUSION

Pleasurable hallucinations can be detected in a substantial proportion of patients, and cross validated with existing instruments.

The association of inequality with the incidence of schizophrenia--an ecological study

BACKGROUND

Socio-economic factors are known to be associated with schizophrenia, but no studies have investigated the effect of inequality on incidence rates of schizophrenia. The aim of the study was to determine whether those electoral wards with greater inequality have a higher incidence of schizophrenia.

METHOD

An ecological study was carried out involving a retrospective case record study to calculate the incidence of schizophrenia across wards in Camberwell, South London for the period 1988-1997, and an index of inequality within each ward was calculated.

RESULTS

There was no significant effect of inequality overall. However, in the group of deprived wards, the incidence of RDC schizophrenia increased as inequality increased (IRR 3.79, 95 %CI 1.25.11.49 p = 0.019 after adjusting for age, sex, absolute deprivation, ethnicity, proportion of ethnic minorities and the interaction between individual ethnicity and proportion of ethnic minorities.

CONCLUSION

Increased inequality is associated with increasing incidence of schizophrenia, but only in the most deprived areas. This is independent of other known social risk factors.

The wider social environment and mental health service use

OBJECTIVE

Previous studies associating neighbourhood context with mental health service use typically included limited sets of confounders.

METHOD

A data set including patients registered in a Case Register and population controls was subjected to multilevel analyses, including neighbourhood exposures and individual level confounders. In addition, days of care consumption of patients was addressed.

RESULTS

The association between socioeconomic deprivation and social capital on the one hand and mental health service use rates on the other could be attributed to individual level differences. However, number of days of service consumption was higher in neighbourhoods with more informal social control. In residentially stable neighbourhoods only, socioeconomic deprivation was associated with lower levels of service consumption.

CONCLUSION

Higher levels of social control may induce patients to remain in contact with mental health services. Furthermore, higher levels of deprivation in neighbourhoods with little population mobility may result in reduced expectations of recovery and/or increased tolerance.

Sex differences in emotional reactivity to daily life stress in psychosis

BACKGROUND

The expression of schizophrenia has been reported to differ between the sexes. The current study investigates whether these sex differences in clinical expression are reflected in one underlying mechanism that may be causally related to psychosis, namely increases in stress sensitivity in daily life.

METHOD

Forty-two participants (22 men, 20 women) with Research Diagnostic Criteria-defined psychotic disorder in a state of clinical remission were studied with the Experience Sampling Method (a structured diary technique assessing current context and mood in daily life) to assess (1) appraised subjective stress related to daily events and activities and (2) emotional reactivity conceptualized as changes in both negative affect and positive affect in relation to the subjective stress. Data were collected from January 1997 to May 1999.

RESULTS

Multilevel regression analyses revealed that women reported a significantly (p < .05) increased emotional reactivity to daily life stress compared with men, reflected in both an increase in negative affect and a decrease in positive affect.

CONCLUSION

These results suggest that gender differences may not be limited to the characteristics of psychosis but may also be reflected in underlying etiologic mechanisms. Furthermore, these results might strengthen the hypothesis that women are more susceptible than men to a schizoaffective expression of schizophrenia.

Is the excess risk of psychosis-like experiences in urban areas attributable to altered cognitive development?

BACKGROUND

Rates of psychotic disorder and related attenuated psychotic experiences are higher in urban areas. We examined to what degree differences between urban and rural areas could be attributed to differences in cognitive development.

METHOD

Scores on the nine subscales of the schizotypal personality questionnaire (SPQ) as well as IQ and specific neuropsychological functions of memory and attention were assessed in a representative sample of 943 young army conscripts from the 49 counties of Greece.

RESULTS

Young men from urban areas had higher scores on the SPQ subscale Odd beliefs/magical thinking (OR = 1.99, 95% CI: 1.42, 2.78), but lower scores on Excessive social anxiety (OR = 0.63, 95 % CI: 0.49, 0.81) and No close friends (OR = 0.42, 95% CI: 0.29, 0.62). Adjustment for demographic factors, IQ and specific neuropsychological functions did not change the results. When the lower scores on Excessive social anxiety and No close friends were taken into account, the differences on the Odd beliefs/magical thinking subscale became even more pronounced (OR = 2.33, 95% CI: 1.56, 3.49).

CONCLUSIONS

Young men from urban areas are socially more competent, but display higher levels of positive psychotic experiences, which are not mediated by lower IQ or higher levels of neuropsychological impairment.

The role of age in the development of Schneiderian symptoms in patients with a first psychotic episode

OBJECTIVE

The likelihood of developing psychotic symptoms greatly increases after puberty. In acute psychotic disorders, first rank symptoms (FRS) are prevalent and considered useful for the diagnostic process. The aim of this study was to test for a linear association between age and the probability of occurrence of FRS in patients with a first psychotic episode (FPE).

METHOD

A total of 112 patients, consecutively admitted with an FPE, were included at baseline and evaluated yearly over a 3-year period using SCID-I and a checklist of 11 items of FRS.

RESULTS

FRS were documented for 65.2% patients at baseline. There was a dose-response relationship in the association between age and FRS. There was no interaction with sex or with final diagnostic category.

CONCLUSION

Variation in the expression of the core positive symptoms of psychosis is subject to the influence of underlying age-dependent maturational processes both in terms of occurrence and level of severity.

Childhood abuse as a risk factor for psychotic experiences

OBJECTIVE

To examine the hypothesis that individuals from the general population who report childhood abuse are at increased risk of developing positive psychotic symptoms.

METHOD

Data were derived from a general population sample of 4045 subjects aged 18-64 years. First ever onset of positive psychotic symptoms at 2-year follow-up were assessed using the Composite International Diagnostic Interview and additional clinical interviews if necessary. Childhood abuse was assessed at baseline.

RESULTS

Baseline reported childhood abuse predicted development of positive psychotic symptoms associated with need for care [odds ratio (OR) = 11.5, 95% CI 2.6-51.6]. This association remained after adjustment for demographic variables, reported risk factors and presence of any lifetime psychiatric diagnosis at baseline (OR = 7.3, 95% CI 1.1-49.0).

CONCLUSION

The results suggest that early childhood trauma increases the risk for positive psychotic symptoms. This finding fits well with recent models that suggest that early adversities may lead to psychological and biological changes that increase psychosis vulnerability.

First admissions for mood disorders in immigrants to the Netherlands

BACKGROUND

The risk of developing schizophrenia is increased for immigrants to the Netherlands from Surinam, the Netherlands Antilles and Morocco, but not for immigrants from Turkey. We examined, in these groups, the risks of a first admission for manic-depressive psychosis.

METHODS

The Dutch Psychiatric Registry provided two datasets. The first referred to first admissions for manic-depressive psychosis (MDP), manic or circular type, in the period 1990-1996, the second to first admissions for MDP, depressed type. MDP, depressed type, corresponds (broadly) to the DSM-IV category of major depressive disorder and MDP, manic or circular type, to the DSM-IV category of bipolar I disorder. The Dutch Central Bureau for Statistics provided yearly population figures.

RESULTS

There were only small increases in the risks of a first admission for MDP, manic or circular type, for immigrants from Surinam (age- and sex-adjusted RR = 1.14; 95% CI: 0.97-1.33) and the Netherlands Antilles (RR = 1.41; 1.10-1.80). This risk was not clearly increased for immigrants from Morocco. The risks for MDP, depressed type, were increased for males from Morocco (age-adjusted RR = 2.17; 1.72-2.72) and Turkey (RR = 1.83; 1.46-2.30), and significantly decreased for females in all of the immigrant groups.

CONCLUSION

We found no evidence for a large increase in the incidence of MDP, manic or circular type, in the immigrant groups, whereas an increase in MDP, depressed type, was observed only in selected groups. Female immigrants suffering from MDP, depressed type, may be underserved.

Neighbourhood socioeconomic disadvantage and behavioural problems from late childhood into early adolescence

STUDY OBJECTIVE

This study investigates whether neighbourhood socioeconomic disadvantage may contribute to child behavioural and emotional problems, beyond the effects of parental socioeconomic status. It also examines the influence of neighbourhood disadvantage on changes in the frequency of behavioural problems from late childhood into early adolescence.

DESIGN AND SETTING

The study was conducted in a large community sample in Rotterdam, the Netherlands. An index of neighbourhood socioeconomic disadvantage was calculated for each of the city's 74 neighbourhoods. Multilevel regression analysis estimated effects of neighbourhood disadvantage and individual variables (parental socioeconomic status, child's gender, and age) on behavioural problems reported by children (Youth Self-Report) and parents (Child Behavior Checklist) and on changes in these scores over a two year follow up.

PARTICIPANTS

A cohort of all children born in 1978 and living in Rotterdam. Of those eligible, 73% (n=2587) participated in the first measurement (T1), at 10-12 years; 71% of the T1 respondents participated again two years later (T2), at 12-14 years.

MAIN RESULTS

Neighbourhood disadvantage was associated with higher Total, Internalising, and Externalising Problems, as assessed with both the Child Behavior Checklist and the Youth Self-Report, even after controlling for parental socioeconomic status. Neighbourhood disadvantage also seemed to contribute to increases in Total Problems over the follow up.

CONCLUSIONS

Living in a disadvantaged neighbourhood is associated with greater behavioural problems and may lead to an exacerbation of problems as children move from childhood into adolescence. Public health interventions to improve child mental health must take the neighbourhood environment into account.

Suicide and attempted suicide among people of Caribbean origin with psychosis living in the UK

BACKGROUND

A report from a 1980s cohort claimed that suicidal behaviour was four times less common in UK-resident people of Caribbean origin with psychosis than in British Whites. Since then, evidence has accumulated that the rate of suicide and suicidal ideation has been increasing. Aims To compare rates of suicidal behaviour in people of Caribbean and British White origin in a large multi-centre sample of patients with psychosis.

METHOD

A secondary analysis of 708 patients with psychosis followed up for 2 years. Outcome measures of reported suicide and attempted suicide were adjusted for socio-economic and clinical differences between groups at baseline.

RESULTS

People of Caribbean origin had a lower risk of suicidal behaviour than British Whites (odds ratio adjusted for age and gender 0.49, 95% CI 0.26-0.92). There was a strong negative interaction between ethnic group and age: suicidal acts were four times less likely in people of Caribbean origin aged over 35 years compared with British Whites, but there was no large or significant difference in those under 35.

CONCLUSIONS

The previously reported lower relative risk of suicidal behaviour in people of Caribbean origin with psychosis is restricted to those over 35 years, suggesting that the protective effect of Caribbean origin is disappearing in younger generations.