Schizophrenia and Afro-Caribbeans. A case-control study

Psychosis, migration and social environment: an age-and-gender controlled study

Purpose

Adverse social experiences are frequently invoked to explain the higher rate of psychosis among migrant groups. The aim of the present study was to establish the socio-environmental factors distinguishing migrant psychotic patients from autochthonous patients.

Subjects and method

We conducted a cross-sectional survey involving 341 migrant psychotic patients matched for age and gender with 341 autochthonous psychotic patients.

Results

Migrant patients lived more often with their parental family, were less often enrolled with a referral psychiatrist, presented a lower rate of employment, a lower percentage of alcohol misuse and of suicide attempts.

Discussion

Our findings add to the growing body of results showing that more attention needs to be focused on socio-environmental variables in psychosis research. However, several limitations have to be taken into account, particularly with regard to selection biases and age of onset of the psychotic illness.

Conclusion

Our results are compatible with the hypothesis that unemployment is a contributing factor in the risk for psychosis among migrant groups. Migrants’ families are an important keystone in the mental health care process of their sick relatives. Our service models need to be adapted with the aim to make the treatment easier for migrant patients.

What is an Afro-Caribbean? Implications for psychiatric research

The term Afro-Caribbean is used to describe black people of Caribbean origin in Britain. Migrants from the Caribbean, their children and their children's children are all covered by this term. The group as a whole is reported to have a higher incidence rate of schizophrenia than white groups, (King et al 1994), and British-born children of Caribbean parents have an even higher rate (Harrison et al, 1988). These reports have led to the hypothesis that Afro-Caribbeans may have a special vulnerability to schizophrenia. While limitations to these studies have been identified, (Wessly et al 1991) none has sought to question the use of the term Afro-Caribbean as a valid and reliable ethnic grouping. If we are to be able to produce good hypotheses for the aetiology of the reported increases in incidence, or to produce research which is useful to Black and ethnic minority groups, we need a clear understanding of the people under study.

Mental illness in Black and Asian ethnic minorities: pathways to care and outcomes

A substantial body of research indicates that, for people from Black and Asian ethnic minorities, access to, utilisation of and treatments prescribed by mental health services differ from those for White people (Lloyd & Moodley, 1992; for a review see Bhui, 1997). Pathways to mental health care are important, and the widely varying pathways taken in various societies may reflect many factors: the attractiveness and cultural appropriateness of services; attitudes towards services; previous experiences; and culturally defined lay referral systems (Goldberg, 1999). Contact with mental health care services may be imposed on the individual, but people who choose to engage with services usually do so only if they think that their changed state of functioning is health-related and potentially remediable through these services. In such cases, they will contact whoever they perceive to be the most appropriate carer, and these carers are often not part of a national health care network.

Ideology, Camouflage or Contingency? Racism in British Psychiatry

"...Are we so sure that the racist form of intolerance results chiefly from the wrong ideas of this or that group of people about the dependence of cultural evolution on organic evolution? Might not these ideas be simply ideological camouflage for more concrete oppositions based on a desire to subjugate other groups and maintain a posi tion of power?"

Effects of a culturally sensitive assessment on symptom profiles in native Dutch and Moroccan patients with a first psychosis referral

Previous studies have reported a higher incidence of psychosis in Moroccan immigrants in the Netherlands than among native-born residents. However, this disparity was substantially attenuated when cultural differences in symptom presentation were taken into account. To better understand the impact of different diagnostic procedures on incidence rates, we examined the effects of the use of a culturally sensitive diagnostic interview, compared to a standard semi-structured diagnostic interview, on symptom profiles among Moroccan immigrant and native Dutch patients in the Netherlands. A total of 26 Dutch and 26 Moroccan patients referred with a possible first psychosis diagnosis were interviewed twice: once with the standard version and once with a culturally adapted version of the Comprehensive Assessment of Symptoms and History questionnaire (CASH and CASH-CS, respectively). Among native Dutch patients, symptoms profiles based on CASH and CASH-CS interviews were very similar. By contrast, among Moroccan immigrant patients, symptom profiles based on CASH and CASH-CS interviews differed substantially, with more mania symptoms (+30%; p < .05) and fewer delusions (-31%; p < .05) reported when using the CASH-CS. These results suggest that the over-diagnosis of schizophrenia in Moroccan immigrants with a first psychosis referral may be related to a tendency to under-detect mood symptoms and over-detect positive psychotic symptoms when a standard diagnostic procedure is used. This bias may be corrected, at least in part, by the use of a culturally sensitive interview instrument such as the CASH- CS.

The Concept of Schizophrenia: From Unity to Diversity

After over 100 years of research without clarifying the aetiology of schizophrenia, a look at the current state of knowledge in epidemiology, genetics, precursors, psychopathology, and outcome seems worthwhile. The disease concept, created by Kraepelin and modified by Bleuler, has a varied history. Today, schizophrenia is considered a polygenic disorder with onset in early adulthood, characterized by irregular psychotic episodes and functional impairment, but incident cases occur at all ages with marked differences in symptoms and social outcome. Men’s and women’s lifetime risk is nearly the same. At young age, women fall ill a few years later and less severely than men, men more rarely and less severely later in life. The underlying protective effect of oestrogen is antagonized by genetic load. The illness course is heterogeneous and depressive mood the most frequent symptom. Depression and schizophrenia are functionally associated, and affective and nonaffective psychoses do not split neatly. Most social consequences occur at the prodromal stage. Neither schizophrenia as such nor its main symptom dimensions regularly show pronounced deterioration over time. Schizophrenia is neither a residual state of a neurodevelopmental disorder nor a progressing neurodegenerative process. It reflects multifactorial CNS instability, which leads to cognitive deficits and symptom exacerbations.

Evidence for phenotypic plasticity in response to photic cues and the connection with genes of risk in schizophrenia

Numerous environmental factors have been identified as influential in the development of schizophrenia. Some are byproducts of modern life, yet others were present in our evolutionary past and persist to a lesser degree in the current era. The present study brings together published epidemiological data for schizophrenia and data on variables related to photic input for places of residence across geographical regions, using rainfall as an inverse, proxy measure for light levels. Data were gathered from the literature for two countries, the former Yugoslavia and Ireland, during a time in the early 20th century when mobility was relatively limited. The data for Yugoslavia showed a strong correlation between hospital census rates for schizophrenia (by place of birth) and annual rain (r = 0.96, p = 0.008). In Ireland, the hospital census rates and first admissions for schizophrenia (by place of permanent residence) showed a trend for correlation with annual rain, reaching significance for 1st admissions when the rainfall data was weighted by the underlying population distribution (r = 0.71, p = 0.047). In addition, across the years 1921-1945, birth-year variations in a spring quarter season-of-birth effect for schizophrenia in Ireland showed a trend for correlation with January-March rainfall (r = 0.80, p ≤ 0.10). The data are discussed in terms of the effect of photoperiod on the gestation and behavior of offspring in animals, and the premise is put forth that vestigial phenotypic plasticity for such photic cues still exists in humans. Moreover, genetic polymorphisms of risk identified for psychotic disorders include genes modulated by photoperiod and sunlight intensity. Such a relationship between phenotypic plasticity in response to a particular environmental regime and subsequent natural selection for fixed changes in the environmentally responsive genes, has been well studied in animals and should not be discounted when considering human disease.

A plausible model of schizophrenia must incorporate psychological and social, as well as neuro developmental, risk factors

Subtle alterations in brain development caused by genes or early environmental hazards, such as obstetric complications, play a role in projecting some individuals on a trajectory toward schizophrenia. High-risk and cohort studies demonstrate that children destined to develop schizophrenia tend to have delayed milestones and subtle neuromotor and cognitive impairments (particularly in coordination and language). These neurocognitive problems lead to difficulties in interpersonal relations, and their progressive alienation makes these at-risk children more likely to harbor odd or paranoid ideas. This cascade of increasingly deviant development may then be compounded by brain maturational changes during adolescence with a resultant lability of the dopaminergic response to stress. As a result, the individual is more susceptible to the effects of the abuse of dopamine-releasing drugs, and to other risk factors such as migration or stressful life events; social isolation may be a common pathway underlying several of the social risk factors.

The influence of gender on clinical and social characteristics of patients at psychosis onset: A report from the Psychosis Incident Cohort Outcome Study (PICOS)

BACKGROUND. This paper examined the hypothesis that males with first-episode psychosis (FEP) experience lower pre-morbid adjustment, greater social disability and more self-perceived needs at illness onset than females(by controlling for duration of untreated psychosis, diagnosis, age and symptoms at onset). Results disconfirming this hypothesis were thought to suggest the potentially mediating role of social context in determining the impact of symptoms and disability on the everyday lives of male patients in the early phase of psychosis. METHOD. A large epidemiologically representative cohort of FEP patients (n=517) was assessed within the Psychosis Incident Cohort Outcome Study (PICOS) framework – a multi-site research project examining incident cases of psychosis in Italy's Veneto region. RESULTS. Despite poorer pre-morbid functioning and higher social disability at illness onset, males reported fewer unmet needs in the functioning domain than females did. An analysis of help provided by informal care givers showed that males received more help from their families than females did. This finding led us to disconfirm the second part of the hypothesis and suggest that the impact of poorer social performance and unmet needs on everyday life observed in male patients might be hampered by higher tolerance and more support within the family context.CONCLUSIONS. These findings shed new light on rarely investigated sociocultural and contextual factors that may account for the observed discrepancy between social disability and needs for care in FEP patients. They also point to a need for further research on gender differences, with the ultimate aim of delivering gender-sensitive effective mental health care.

Understanding patients in multicultural settings: a personal reflection on ethnicity and culture in clinical practice

OBJECTIVE

To identify and discourse on the complexities of ethnicity and culture, their role in the social and psychological functioning of patients and their potential impact on clinical assessment and treatment of these patients in diverse cultural contexts.

DESIGN

Description of aspects of the cultural competence required by clinicians in mental health service provisions in therapeutic interactions involving the therapist and patient and also in the encounter between practitioners.

RESULTS

The four-decade clinical experience of the author, an African Jamaican psychiatrist, encompasses clinical experience in the Caribbean, North America, Europe and New Zealand. From this wealth of multicultural clinical practice the author uses personal examples of four experiences with patients and professionals of African Caribbean, British and Maori ethnicities to discuss issues of ethnicity, ethnic identity and stereotyping, culture, cultural competency and alterity in the exchanges between the therapist and patient, and between therapists and the difficulties encountered in effective assessment and treatment of patients in multicultural settings. The author highlights the importance of historical experience in the psychological constitution of patients, which is the basis of a novel analytic model called psychohistoriography. This insight-oriented individual or group-focused intervention was created with the intention of attempting to heal the wounds of history; an aim that is absent from existing psychoanalytic treatment modalities.

CONCLUSION

Psychohistoriography may be a viable therapeutic option in the negotiation of cross-cultural clinical interactions.

Predictive validity of a culturally informed diagnosis of schizophrenia: a 30 month follow-up study with first episode psychosis

Previous research has shown discrepancies between a standard diagnostic interview for schizophrenia (CASH) and a culture sensitive version of this instrument (CASH-CS) in Moroccan patients. More specifically we showed that among Moroccan immigrants the CASH-CS resulted in fewer patients with a diagnosis of schizophrenia compared with diagnoses based on the CASH, whereas for Native Dutch patients there was no difference between the CASH and the CASH-CS. The aim of the current study was to compare the predictive validity of a diagnosis of schizophrenia according to the CASH and CASH-CS.

METHOD

Thirty months after referral, 26 Moroccan and 26 native Dutch patients with a suspected first psychotic episode were compared with regard to 30-month diagnostic stability, symptom development, psychosocial functioning, medication use and hospitalization using baseline diagnoses based on the two versions of the CASH.

RESULTS

Moroccan patients who were diagnosed with schizophrenia using the standard CASH at baseline had a significantly better 30-month prognosis than native Dutch patients with the same CASH diagnosis. Prognosis of schizophrenia according to the CASH-CS was similar for Moroccans and native Dutch patients. Diagnostic stability according to the CASH was high for native Dutch (92%), but low for Moroccan patients (27%), whereas diagnostic stability according to the CASH-CS was high for both groups (85% and 81%, respectively).

CONCLUSION

These data raise questions regarding the validity of the standard CASH in Moroccan immigrants in The Netherlands and support the validity of the CASH-CS. As a consequence, there are serious doubts about the validity of previous studies showing an increased incidence of schizophrenia in immigrants using standard diagnostic procedures.

Ethnicity and access to an inner city home treatment service: a case-control study

There is strong evidence suggesting ethnic variations in mental health service use and disproportionate numbers of people of black ethnic origin being admitted to hospital. The objective of this study was to establish whether people of black ethnic origin had equal access to home treatment in a mental health crisis. Using a case-control design, we selected a random sample of 240 inpatient episodes and compared them with a sample of 77 home treatment episodes over a 12-month period (1 April 2008-31 March 2009). We found no difference in the proportion of people of black ethnic origin being home treated in comparison to receiving an inpatient admission, although they experienced longer hospital admissions than people of other ethnic origin. Diagnosis, housing status and source of referral were found to be significant in influencing the choice of intervention in our multivariate analysis. People of black ethnic origin were found to use home treatment to the same extent as other ethnic groups in a mental health crisis, but further research is required for the early discharge function of home treatment teams to evaluate whether this aspect of care is experienced differently by different ethnic groups.

The epidemiology of schizophrenia: replacing dogma with knowledge

Major advances have been made in our understanding of the epidemiology of schizophrenia. We now know that the disorder is more common and severe in young men, and that the incidence varies geographically and temporally. Risk factors have been elucidated; biological risks include a family history of the disorder, advanced paternal age, obstetric complications, and abuse of drugs such as stimulants and cannabis. In addition, recent research has also identified social risk factors such as being born and brought up in a city, migration, and certain types of childhood adversity such as physical abuse and bullying, as well as social isolation and adverse events in adult life. Current research is focussing on the significance of minor psychotic symptoms in the general population, gene-environmental interaction, and how risk factors impact on pathogenesis; perhaps all risk factors ultimately impact on striatal dopamine as the final common pathway.

First contact incidence of psychotic disorders among native Dutch and Moroccan immigrants in the Netherlands: influence of diagnostic bias

BACKGROUND

Several studies have reported increased incidence rates of psychotic disorders among immigrant groups. Surprisingly, the cross-cultural validity of the diagnostic instruments that were used was never tested.

AIMS

To examine whether the incidence rates of psychotic disorders including schizophrenia among Moroccan immigrants to the Netherlands remain increased when a cultural sensitive diagnostic interview is used.

METHOD

We compared first contact incidence with a standard and a cultural sensitive version of a diagnostic interview.

RESULTS

Age and gender adjusted relative risk for psychotic disorders and schizophrenia among Moroccans compared to native Dutch was 7.9 (95% CI 4.7-13.5) and 7.8 (95% CI 4.0-15.2) respectively based on the standard diagnostic interview and 4.2 (95% CI 2.3-7.9) and 1.5 (0.5-4.3) respectively based on the cultural sensitive version the diagnostic interview.

CONCLUSION

First contact incidence of schizophrenia among Moroccans was no longer significantly higher than among ethnic Dutch people when a cultural sensitive diagnostic procedure was applied.

The mental health of Korean immigrants in São Paulo, Brazil

This study investigated the frequency of lifetime mental disorders among Korean immigrants in the city of São Paulo, Brazil. Snowball sampling with multiple focuses was used to recruit Korean immigrants older than 18 years and living in São Paulo. A total of 324 Korean immigrants were selected and their mental status was evaluated using a structured interview, namely the Portuguese or the Korean version of the Composite International Diagnostic Interview 2.1. The diagnoses of mental disorders were made according to the ICD-10. The frequency of any lifetime psychiatric disorder was 41.9%. The frequencies of main disorders were: anxiety disorder, 13% (post-traumatic stress disorder, 9.6%); mood disorder, 8.6%; somatoform disorders, 7.4%; dissociative disorder, 4.9%; psychotic disorder, 4.3%; eating disorder, 0.6%; any substance (tobacco, alcohol, drugs) use disorder, 23.1%. The frequency of any psychiatric disorder except alcohol and tobacco use disorders was 26.2%. Korean immigrants have more psychiatric disorders than the Korean population in Korea, particularly post-traumatic stress disorder, and almost the same rate as the Brazilian population. Mental health authorities should promote a healthier integration and the development of culturally sensitive mental health programs for Korean immigrants.

Social defeat and the culture of chronicity: or, why schizophrenia does so well over there and so badly here

The history of the way schizophrenia has been conceptualized in American psychiatry has led us to be hesitant to explore the role of social causation in schizophrenia. But there is now good evidence for social impact on the course, outcome, and even origin of schizophrenia, most notably in the better prognosis for schizophrenia in developing countries and in the higher rates of schizophrenia for dark-skinned immigrants to England and the Netherlands. This article proposes that "social defeat" may be one of the social factors that may impact illness experience and uses original ethnographic research to argue that social defeat is a common feature of the social context in which many people diagnosed with schizophrenia in America live today.

Psychotic experiences in the general population: a twenty-year prospective community study

PURPOSE

Recent work suggested that psychosis might be expressed at subclinical levels. However, the determinants of subclinical psychotic symptoms, the degree of continuity over the life span, and the impact on functioning remain unclear. Thus we analyzed the prevalence, determinants, patterns and impact of subclinical psychotic symptoms in a community cohort over a 20-year period.

METHODS

The Zurich Study - a longitudinal community study - started in 1979 with a sample of 591 participants aged 20/21 years. Follow-up interviews were conducted at age 23, 28, 30, 35 and 41. Symptoms were assessed with a semi-structured interview and the SCL90-R. In this analysis, items of the SCL90-R symptom dimensions "paranoid ideation" and "psychoticism" were examined.

RESULTS

Two distinct symptom dimensions of subclinical psychosis became evident, one representing schizophrenia nuclear symptoms, the other representing schizotypal signs. Cannabis use in adolescence was associated specifically with schizophrenia nuclear symptoms, whereas childhood adversity as well as chronic physical or mental disorders in parents contributed to schizotypal signs. Individuals with a persistently high level of either of the two identified symptom dimensions over 20 years experienced significant deficiencies in social achievement and functioning.

CONCLUSIONS

Expression of psychotic symptoms in populations is continuous and characterized by differing levels of severity and persistence. A small group of individuals displays persistence of subclinical psychotic symptoms over a period of 20 years. The causes of and pathways to clinical psychotic disorder can be studied long before the disorder becomes clinically relevant.

CAOS contribution to understanding cultural/ethnic differences in the prevalence of bipolar affective disorder in New Zealand

OBJECTIVE

To examine whether data on the clinical profiles of psychiatric service users can inform the claim that Māori in the New Zealand community have an increased rate of bipolar disorder.

METHOD

The standardized recordings of a variety of clinical phenomena previously collected in a New Zealand study of psychiatric service users was extracted for those persons who were diagnosed with a bipolar mental disorder. The individual clinical phenomena were then compared by ethnicity.

RESULTS

The most dramatic result was the increased recording of high levels of overactivity or disruptive aggressive behaviour in Māori compared with European in psychiatric service users, despite which, the rates of the disorder did not significantly differ by ethnicity.

CONCLUSION

In the community survey lay raters were deciding on the presence or absence of phenomena including hyperactivity without the contextual knowledge that clinicians use. It is possible that the Composite International Diagnostic Interview decision tree was being fed an excessive amount of that criterion.

Social exclusion and risk of emergency compulsory admission. A case-control study

BACKGROUND

Emergency detentions under section 4 of the Mental Health Act 1983 are more frequent in socially deprived areas of England and Wales. However, it is not clear whether individual socio-economic disadvantage increases likelihood of emergency detention. Therefore, this study tests the hypothesis that a higher proportion of people who are socially excluded will be admitted to hospital under section 4 than those who are not.

METHODS

A total of 300 mental health act assessments in two London boroughs with different rates of section 4 admissions were studied by retrospective case note review in a case-control design. An index of social exclusion was created and piloted for this study.

RESULTS

The logistic regression analysis discovered four risk factors for section 4 admissions: presenting with a risk to self or others at the mental health act assessment, bi-polar affective disorder, non-White British ethnicity and low social support. There were no significant differences between the two boroughs on these variables. Risk factors for any compulsory admission were: presenting with a risk, psychosis and non-White British ethnicity.

CONCLUSION

This study found low social support to be the only social exclusion indicator that increases likelihood of admission under section 4. While individual-level variables explain some of the variation in section 4 rates, it is likely that, as indicated by other studies, different configurations of mental health services affect rates to a greater degree.

Psychiatric disorders and social characteristics among second-generation Moroccan migrants in Belgium: an age-and gender-controlled study conducted in a psychiatric emergency department

PURPOSE

Clinically, one of the most consistent clinical findings among migrant patients is an increase in the rate of psychosis. The aim of the present study was to confirm this finding in Belgium by comparing second-generation Moroccan migrant patients with Belgian patients, matched for the variables of age and gender.

SUBJECTS AND METHOD

We conducted a cross-sectional survey on 272 patients admitted in a psychiatric emergency unit during the year 1998. We used univariate and multivariate analyses to compare the two subgroups.

RESULTS

Multivariate analyses showed that migrant patients lived more often with their parental family and that they presented a higher rate of admission for psychotic disorders and a lower rate of employment.

DISCUSSION

Our findings add to the growing body of results showing increased incidence of psychosis among immigrants to European countries, but several factors have to be taken into account, particularly with regard to selection biases and differences in help-seeking behaviour and in family perception of the mental illness.

CONCLUSION

Our results are compatible with the hypothesis that unemployment is a contributing factor in the risk for psychosis among migrant groups. Further studies would be needed to better explain some of our results, particularly the role played by the families of migrant patients.

Psychosis in high-security and general psychiatric services: report from the UK700 and special hospitals' treatment resistant schizophrenia groups

BACKGROUND

Serious violence is an unusual but significant correlate of psychosis, and leads to the need for specialist secure psychiatric services. Most such service users have previously used general psychiatric services.

AIMS

To examine diagnostic and socio-demographic differences between high-security psychiatric service users from their peers in community services.

METHOD

Two groups of patients with psychosis were compared: a national sample of high-security hospital residents, and a sample of patients in contact with general psychiatric services.

RESULTS

Schizophrenia was the almost invariable diagnosis for all special hospital patients. White patients in the community sample were significantly more likely to have affective components to their illness compared with African-Caribbean patients; unlike those in special hospitals. There was a small excess in the proportion of African-Caribbean patients in the special hospital group, controlling for diagnosis, gender and locality. Men were overrepresented in this group.

CONCLUSIONS

Among patients with psychosis, having a diagnosis of schizophrenia and being male increase the likelihood of special hospital admission. Suggestions that ethnic minority patients are much more likely to have engaged in serious violence and need high-security placement were not borne out.

Evaluating the use of a psychiatric intensive care unit: is ethnicity a risk factor for admission?

OBJECTIVE

This paper presents a descriptive study, undertaken in 1993, of a Psychiatric Intensive Care Unit (PICU) serving a deprived inner-city area, investigating the role of ethnicity as a risk factor for admission to the unit.

METHODS

Clinical and demographic data were collected on consecutive admissions to a PICU. Global Assessment of Function Scale scores were rated on admission and at discharge from the unit.

RESULTS

The majority of patients were male (63%) and the commonest DSM-IV diagnoses were schizophrenia (42%) and bipolar affective disorder (24%). Average length of stay was 13 days with patients making significant improvement in functioning during their stay. Fifty-five percent of PICU admissions came from ethnic minorities (compared with 25.6% of total hospital admissions and 20.9% of the local catchment area population aged between 16 and 65 years). There was no evidence that ethnic minority patients were being inappropriately admitted to the PICU.

CONCLUSIONS

It is likely that a variety of factors contributed to the high rate of PICU admission amongst ethnic minority patients, including an increased prevalence of major mental illness and more frequent cannabis abuse.

Studies of anticipation in bipolar affective disorder

Anticipation refers to the increase in disease severity or decrease in age of onset in successive generations. The concept evolved from the theories and dogma of degeneration that were pervasive in psychiatry and medicine in the late 19th century and into the early 20th century. The term was set aside with the criticism of geneticist Lionel Penrose, who argued that anticipation was the result of ascertainment biases. The renewed interest in anticipation followed the identification of its molecular genetic basis in the form of unstable trinucleotide repeats. Subsequently, several diseases have been studied clinically for the presence of anticipation. Although anticipation has been identified in many diseases, including bipolar disorder, only diseases showing a pattern of progressive neurodegeneration have been associated with unstable trinucleotide repeats. This review summarizes the research on anticipation in bipolar disorder and other secular trends in the patterns of the illness such as the cohort effect. The changing nature of bipolar disorder is likely to be a result of combined influences from several genes, some of which are likely to be in a state of flux, as well as environmental or cultural forces that converge to give the clinical picture of anticipation.

Occurrence of hallucinatory experiences in a community sample and ethnic variations

BACKGROUND

Hallucinations typically are associated with severe psychiatric illness but also are reported by individuals with no psychiatric history.

AIMS

To examine the prevalence of hallucinations in White and ethnic minority samples using data from the Fourth National Survey of Ethnic Minorities.

METHOD

Interviews of 5196 ethnic minority and 2867 White respondents were carried out. The respondents were screened for mental health problems and the Psychosis Screening Questionnaire asked about hallucinations. Those who screened positive underwent a validation interview using the Present State Examination.

RESULTS

Four per cent of the White sample endorsed a hallucination question. Hallucinations were 2.5-fold higher in the Caribbean sample and half as common in the South Asian sample. Of those who reported hallucinatory experiences, only 25% met the criteria for psychosis.

CONCLUSIONS

The results provide an estimate of the annual prevalence of hallucinations in the general population. The variation across ethnic groups suggests cultural differences in these experiences. Hallucinations are not invariably associated with psychosis.

Incidence of schizophrenia in ethnic minorities in London: ecological study into interactions with environment

OBJECTIVE

To determine whether the incidence of schizophrenia among people from non-white ethnic minorities is greater in neighbourhoods where they constitute a smaller proportion of the total population.

DESIGN

Ecological design including retrospective study of case records to calculate the incidence of schizophrenia in the ethnic minority population across electoral wards and multi-level analysis to examine interaction between individuals and environment.

SETTING

15 electoral wards in Camberwell, South London.

PARTICIPANTS

All people aged 16 years and over who had contact with psychiatric services during 1988-97.

MAIN OUTCOME MEASURE

Incidence rates of schizophrenia according to Research Diagnostic Criteria.

RESULTS

The incidence of schizophrenia in non-white ethnic minorities increased significantly as the proportion of such minorities in the local population fell. The incidence rate ratio varied in a dose-response fashion from 2.38 (95% confidence interval 1.49 to 3.79) in the third of wards where non-white ethnic minorities formed the largest proportion (28-57%) of the local population to 4.4 (2.49 to 7.75) in the third of wards where they formed the smallest proportion (8-22%).

CONCLUSION

The incidence of schizophrenia in non-white ethnic minorities in London is greater when they comprise a smaller proportion of the local population.

Comparison of the incidence of schizophrenia in rural Dumfries and Galloway and urban Camberwell

BACKGROUND

Being born or living in urban areas is associated with high rates of schizophrenia. However, few studies have compared the incidence in urban/rural areas using the same methodology.

AIMS

To compare service-based incidence rates for schizophrenia in rural Dumfries and Galloway in south-west Scotland with urban Camberwell in south-east London.

METHOD

Using Research Diagnostic Criteria diagnoses from the OPCRIT computer algorithm, we compared the incidence of schizophrenia over 12 years (1979-1984 and 1992-1997) using indirect standardisation techniques and Poisson regression modelling.

RESULTS

The incidence was 61% higher in urban Camberwell than in rural Dumfries and Galloway (standardised incidence ratio (SIR)=1.61; 95% CI=1.42-1.81). There was no difference in incidence when we compared the White population in Camberwell with Dumfries and Galloway (SIR=1.12; 95% CI=0.86-1.43).

CONCLUSIONS

The incidence of schizophrenia in urban Camberwell was higher than that in rural Dumfries and Galloway; the high incidence of non-Whites in Camberwell largely explains the urban/rural difference.

Testing hypotheses on specific environmental causal effects on behavior

There have been strong critiques of the notion that environmental influences can have an important effect on psychological functioning. The substance of these criticisms is considered in order to infer the methodological challenges that have to be met. Concepts of cause and of the testing of causal effects are discussed with a particular focus on the need to consider sample selection and the value (and limitations) of longitudinal data. The designs that may be used to test hypotheses on specific environmental risk mechanisms for psychopathology are discussed in relation to a range of adoption strategies, twin designs, various types of "natural experiments," migration designs, the study of secular change, and intervention designs. In each case, consideration is given to the need for samples that "pull-apart" variables that ordinarily go together, specific hypotheses on possible causal processes, and the specification and testing of key assumptions. It is concluded that environmental risk hypotheses can be (and have been) put to the test but that it is usually necessary to use a combination of research strategies.

Understanding the excess of psychosis among the African-Caribbean population in England. Review of current hypotheses

BACKGROUND

Increased rates of schizophrenia continue to be reported among the African-Caribbean population in England.

AIMS

To evaluate the competing biological, psychological and social explanations that have been proposed.

METHOD

Literature review.

RESULTS

The African-Caribbean population in England is at increased risk of both schizophrenia and mania; the higher rates remain when operational diagnostic criteria are used. The excess of the two psychotic disorders are probably linked: African-Caribbean patients with schizophrenia show more affective symptoms, and a more relapsing course with greater social disruption but fewer chronic negative symptoms, than White patients. No simple hypothesis explains these findings.

CONCLUSIONS

More complex hypotheses are needed. One such links cultural variation in symptom reporting, the use of phenomenological constructs by psychiatrists and social disadvantage.

What risk factors tell us about the causes of schizophrenia and related psychoses

Genetic, epidemiologic, and molecular studies concur that liability to schizophrenia is transmitted through the inheritance of a number of genes of relatively small effect, some of which are shared with other psychoses. Each of these susceptibility genes causes minor deviations that are relatively innocent in themselves, for example, increased lateral ventricular volume, schizotypal personality, or subtle cognitive difficulties. However, when an individual is unlucky enough to inherit several of these traits, their cumulative effect, often compounded by environmental hazards, propels that person over a threshold for the expression of frank psychosis. Early environmental risk factors for schizophrenia include urban and winter birth, fetal malnutrition and hypoxia, and possibly prenatal viral infections; these early hazards have only a modest risk-increasing effect, and operate in the context of genetic risk. Preschizophrenic children are more likely to have minor psychomotor and cognitive problems; low IQ has a linear relationship with risk for schizophrenia. However, schizophrenia is not simply a neurodevelopmental disorder, because risk factors have been identified that have their effects proximal to the onset of psychosis: drug abuse, immigrant status, and social adversity and isolation. Both genetic and environmental risk factors appear to operate across diagnostic categories and therefore support a dimensional model of psychosis.

Early and late environmental risk factors for schizophrenia

Although a high proportion of liability to schizophrenia is under genetic control, a number of environmental risk factors have been identified. The earliest of these are complications of pregnancy and birth, though whether these cause or reflect disturbed brain development is not absolutely clear. Neurodevelopmental deviance is also indicated by neurological dysfunction, social, behavioural and cognitive deficits during childhood. Immigrant status is a significant risk factor, especially prominent among the African Caribbean population in England, though the mechanism is unknown. Later environmental risk factors include adverse life events and substance abuse. An additive model of multiple genetic and environmental risk factors of small effect may be too simplistic and an interactive model where genetic predisposition is compounded by environmental effects is more in keeping with current evidence. The nature of such interactions can be explored more fully when susceptibility genes for schizophrenia are identified.

Outcome of admission to a medium secure psychiatric unit. 2. Role of ethnic origin

BACKGROUND

A follow-up of patients discharged from medium secure psychiatric units is used to compare outcome in patients of different ethnic origin.

AIMS

To test the hypothesis that there are systematic differences in clinical outcome between ethnic groups.

METHOD

A descriptive, longitudinal cohort study of discharges from a medium secure unit is used to compare the 125 patients of White/European ethnic origin and the 104 patients of Black/African-Caribbean origin.

RESULTS

Patients of African-Caribbean origin were admitted at three times the rate of White patients, had a higher prevalence of psychosis and a lower prevalence of personality disorder. There was no difference in outcome as measured by location at follow-up, readmission or re-offending.

CONCLUSIONS

The higher rate of admission of African-Caribbean patients is consistent with a higher level of demand. There is a need for studies of the pathways by which patients from ethnic minorities reach medium-security accommodation, with a view to early intervention.

A Jamaican psychiatrist evaluates diagnoses at a London psychiatric hospital

BACKGROUND

Authors have suggested that the high rate of schizophrenia reported for African-Caribbeans living in the UK is due to misdiagnosis by British psychiatrists.

AIMS

To compare the diagnoses made by a Black Jamaican psychiatrist with those of White British psychiatrists.

METHOD

All in-patients on four wards at the Maudsley hospital were approached for the study; 66 participated: 24 White, 29 Black African-Caribbeans and 13 Blacks from other countries of origin. F.W.H., a Black Jamaican psychiatrist, conducted his standard clinical assessment and performed the Present State Examination (PSE) on these patients. His diagnoses were compared with the case note diagnoses made by British psychiatrists, and with the PSE CATEGO diagnoses.

RESULTS

Of 29 African and African-Caribbean patients diagnosed with schizophrenia, the diagnoses of the British and the Jamaican psychiatrists agreed in 16 instances (55%) and disagreed in 13 (45%). Hence, interrater reliability was poor (kappa = 0.45). PSE CATEGO diagnosed a higher proportion of subjects as having schizophrenia than the Jamaican psychiatrist did (chi 2 = 3.74, P = 0.052).

CONCLUSIONS

Agreement between the Jamaican psychiatrist and his UK counterparts about which patients had schizophrenia was poor. PSE CATEGO may overestimate rates of schizophrenia.

Ethnic differences in the presentation of bipolar affective disorder

There have been repeated reports that Afro-Caribbean people living in the UK are more prone than white people to be diagnosed as having schizophrenia and mania, along with some evidence that they are less likely to receive a diagnosis of depression. We attempted to replicate these findings in a population of patients on lithium prophylaxis. We therefore assessed the clinical characteristics of people under the age of 55 from three ethnic groups attending a lithium clinic in south London, those of (1) white British (n = 88); (2) Afro-Caribbean (n = 31); and, (3) African (n = 15) origin. Nineteen of the white patients met DSM-IV criteria for unipolar depression (UP) and eight met the criteria for bipolar II disorder (BP II); in contrast, only two black patients met the criteria for unipolar depression and none met the criteria for BP II. Among patients diagnosed as BP I, Africans were significantly more likely than whites to show exclusively or mainly manic presentations while Afro-Caribbeans were more likely to have had mood-incongruent delusions. On the other hand, white patients were significantly more likely than Afro-Caribbeans to have had suicidal ideas or actions, and showed a similar but not significant excess when compared with Africans. Our findings could reflect either genuine ethnic differences in the presentation of severe affective disorder or be produced by the failure of British doctors to detect depression and deliver appropriate treatment to their black patients. The frequency with which Afro-Caribbean patients with mania present mood-incongruent delusions probably contributes to the high rates of diagnosed schizophrenia in this population.

Effects of family history and place and season of birth on the risk of schizophrenia

BACKGROUND

Although a family history of schizophrenia is the best-established risk factor for schizophrenia, environmental factors such as the place and season of birth may also be important.

METHODS

Using data from the Civil Registration System in Denmark, we established a population-based cohort of 1.75 million persons whose mothers were Danish women born between 1935 and 1978. We linked this cohort to the Danish Psychiatric Central Register and identified 2669 cases of schizophrenia among cohort members and additional cases among their parents.

RESULTS

The respective relative risks of schizophrenia for persons with a mother, father, or sibling who had schizophrenia were 9.31 (95 percent confidence interval, 7.24 to 11.96), 7.20 (95 percent confidence interval, 5.10 to 10.16), and 6.99 (95 percent confidence interval, 5.38 to 9.09), as compared with persons with no affected parents or siblings. The risk of schizophrenia was associated with the degree of urbanization of the place of birth (relative risk for the capital vs. rural areas, 2.40; 95 percent confidence interval, 2.13 to 2.70). The risk was also significantly associated with the season of birth; it was highest for births in February and March and lowest for births in August and September. The population attributable risk was 5.5 percent for a history of schizophrenia in a parent or sibling, 34.6 percent for urban place of birth, and 10.5 percent for the season of birth.

CONCLUSIONS

Although a history of schizophrenia in a parent or sibling is associated with the highest relative risk of having the disease, the place and season of birth account for many more cases on a population basis.

Schizophrenia: a review of current research and thinking

Schizophrenia is the major mental illness of our time and causes serious disturbances for those with the condition as well as using up significant proportions of scarce health resources. This paper reviews the recent literature on advances in classification, aetiology, epidemiology and treatments. Methodological problems encountered in researching this condition are discussed. Advances in treatments offered for this condition have improved outcomes but whether the patient receives these treatments may depend on what local services are prepared to offer.

The new epidemiology of schizophrenia

A confluence of findings from different vantage points has led to renewed interest and direction in the epidemiology of schizophrenia. This article provides an overview of prevalence and incidence data, examining the validity of reported secular trends in the occurrence of schizophrenia. Advances in molecular genetics have uncovered new linkage on chromosomes 6, 8, and 22 and have suggested complex models, including anticipation, to explain the perpetuation of genetic transmission in the face of low fecundity. Neurotropic viruses and autoimmunity have emerged as pathoplastic mechanisms to explain recent intriguing epidemiologic associations in schizophrenia. Environmental risk factors are also important. With attention to particular risk factors (i.e., perinatal hypoxia), a preventative approach may be realistic for some forms of schizophrenia.

The 100-year epidemiology of schizophrenia

Since Kraepelin delineated dementia praecox as a disease entity construct, epidemiological studies conducted since the beginning of the century have produced remarkably consistent estimates of its prevalence, incidence and lifetime risk across various populations and geographic areas. A similar pattern emerged from the WHO ten-country study on first-contact incidence of schizophrenia. The diagnostic concept of dementia praecox originally used by Kraepelin and that of schizophrenia employed in the WHO studies were found to overlap extensively, indicating continuity over time. However, the findings of a similar incidence of schizophrenia in diverse populations and across time periods are unusual for a multifactorial disease and are compatible with at least two alternative interpretations that have different implications for the search for genetic and environmental causes of the disorder.

Increased rate of psychosis among African-Caribbeans in Britain is not due to an excess of pregnancy and birth complications

BACKGROUND

It has been suggested that the increased rate of psychotic illness among African-Caribbeans living in Britain is due to an excess of pregnancy and birth complications (PBCs).

METHOD

We therefore compared the frequency of PBCs in a group of White psychotic patients (n = 103) and a comparable group of patients of African-Caribbean origin (n = 61); the latter consisted of 30 first-generation (born in the Caribbean) and 31 second-generation (born in Britain) individuals.

RESULTS

White psychotic patients were more than twice as likely to have a history of PBCs as their African-Caribbean counterparts (odds ratio = 2.34, 95% confidence interval (CI) 0.88-6.47, P = 0.062). The same trend was observed among patients with a DSM-III diagnosis of schizophrenia (odds ratio = 1.65, 95% CI 0.56-4.97, P = 0.32). The rate of PBCs was similar among the first- and second-generation Caribbean psychotic patients.

CONCLUSIONS

The increased rate of psychotic illness that has been reported among the African-Caribbean population in Britain is not due to an increased prevalence of PBCs.

Morbid risk of schizophrenia in first-degree relatives of white and African-Caribbean patients with psychosis

BACKGROUND

The high rate of schizophrenia among the second-generation African-Caribbean population in Britain has prompted much concern and speculation. Sugarman and Craufurd have reported that the morbid risk in the siblings of second-generation African-Caribbean schizophrenic patients was unusually high compared with that of the siblings of White patients.

METHOD

We sought to replicate these findings by comparing the morbid risk for schizophrenia in the first-degree relatives of 111 White and 73 African-Caribbean psychotic probands. The latter comprised 35 first-generation (born in the Caribbean) and 38 second-generation (born in Britain) probands.

RESULTS

The morbid risk for schizophrenia was similar for the parents and siblings of White and first-generation African-Caribbean patients, and for the parents of the second-generation African-Caribbean probands. However, the siblings of second-generation African-Caribbean psychotic probands had a morbid risk for schizophrenia that was seven times that of their White counterparts (P = 0.007); similarly, the siblings of second-generation African-Caribbean schizophrenic probands had a morbid risk for schizophrenia that was four times that of their White counterparts (P = 0.05).

CONCLUSIONS

These findings replicate those of the earlier report of Sugarman and Craufurd, and suggest either that the second-generation African-Caribbean population in Britain is particularly vulnerable to some environmental risk factors for schizophrenia, or that some environmental factors act selectively on this population in Britain.

The incidence of mania: time trends in relation to gender and ethnicity

In order to investigate conflicting reports about possible changes in the incidence of mania, we established first contact rates for mania in the defined area of Camberwell between 1965 and 1984. There was some evidence for an increase in the first contact rate of mania, especially in females. This rise may be associated with the influx into Camberwell of individuals of Afro-Caribbean origin who showed significantly higher rates than the white group [adjusted rate ratio 3.1; 95% confidence interval (CI) 1.4-6.9] and more often displayed mixed manic and schizophrenic symptomatology (risk ratio 2.2; 95% CI 1.1-4.3). We conclude that the incidence of mania has not decreased and may actually have increased. High rates of mental illness among members of ethnic minorities are not specific to schizophrenia, suggesting that a risk factor common to both manic and schizophrenic illness is more prevalent among these groups.

Psychopathology of white mentally ill immigrants to Jamaica

OBJECT

To test the hypothesis that white immigrants to a predominantly black country have a different pattern of psychopathology from the native population.

METHOD

The psychopathology (DSM III-R) of white immigrants to Jamaica seen in the author's private practice between 1979 and 1990 was compared with the psychopathology of a control sample of native Jamaicans matched with the immigrant sample for age, sex, and social class.

RESULTS

There was no statistical difference in the major diagnoses mood disorder (35%), anxiety states (27%), and schizophrenia (20%) between the immigrant and control groups. White immigrants to this black country did not develop schizophrenia at higher rates than the native born. White mentally ill immigrants to Jamaica move into social class positions at a significantly higher level (p < 0.005) than those of their parents with whom they grew up in their home country. This was significantly different (p < 0.005) from their Jamaican controls. Two case studies are presented to illustrate these findings.

CONCLUSIONS

The political/economic situation which exists in black postcolonial countries like Jamaica provides a protective social environment for white immigrants, which buffers them from the etiological conditions that engender schizophrenia in immigrants to other countries with predominantly white populations.

Do obstetric complications cause the earlier age at onset in male than female schizophrenics?

We compared the age at onset of 184 patients with functional psychoses with and without a history of obstetric complications (OCs) as defined by the scale of Lewis et al. (1989). OCs had no significant influence on the age at onset in those patients who had affective psychoses or were non-white. There were 73 white patients with a DSM-III-R diagnosis of schizophrenia. The mean age at onset of those 25 who had a history of at least one definite OC was 2.6 years earlier than that of the 48 patients with no history of OCs. This effect was entirely due to the male patients with histories of OCs who had, on average, a 3.5 years earlier age at onset. There were no gender differences in age at onset among schizophrenics without a history of OCs. We suggest that a subgroup of male patients with a history of OCs is responsible for the earlier age at onset in male compared to female schizophrenics.

Ethnic differences in risk of compulsory psychiatric admission among representative cases of psychosis in London

OBJECTIVE

To compare the risk of detention under the Mental Health Act 1983 in a representative group of people with psychotic disorders from different ethnic groups.

SETTING

Two defined geographical areas in south London.

DESIGN

Annual period prevalent cases of psychosis were identified in 1993 in the study areas from hospital and community data. Standardised criteria were applied to case notes to establish diagnosis and detention under the act.

SUBJECTS

535 patients were identified, of whom 439 fulfilled ICD-10 criteria for psychosis.

MAIN OUTCOME MEASURES

Risk of ever having been detained under the Mental Health Act 1983, risk of detention under specific sections of the act during the study year, and risk of contact with forensic services for the different ethnic groups.

RESULTS

439 patients with a psychotic illness were identified. Nearly half of the white patients had been detained under the act compared with 70% and 69% of black Caribbean and black African patients, respectively. Black Caribbean and black African patients were more likely than white patients to have been involuntarily detained (adjusted odds ratio 3.67; 95% confidence interval 2.07 to 6.50 and 2.88; 1.04 to 7.95, respectively). Rates of use of sections 2, 3 and 136 in the study year were higher for black than for white patients, and black patients were more likely than white patients to have been admitted to a psychiatric intensive care facility or prison.

CONCLUSION

Independent of psychiatric diagnosis and sociodemographic differences, black African and black Caribbean patients with psychosis in south London were more likely than white patients to have ever been detained under the Mental Health Act 1983.

Psychotic illness in ethnic minorities: clarification from the 1991 census

Age and sex-adjusted first admission rates for operationally-defined schizophrenia and other non-affective psychosis in different ethnic groups were calculated over the period 1988-1992 in a defined catchment area in South London. Standardized rates for schizophrenia, corrected for age- and gender-related under-reporting in the 1991 census and a 20% underestimate of the size of the ethnic minority populations in the area, were not only higher in the Afro-Caribbean group (SMR: 3.1; 95% C1:2.0-4.7), but also in the African group (SMR: 4.2; 95% C1: 2.8-6.2). It was further found that higher rates were not specific to schizophrenia. These findings suggest that some common factor associated with ethnic minority membership is important in producing an excess of psychotic illness.