Paul Bebbington

A cognitive model of the positive symptoms of psychosis

In the last 10 years a consensus has developed that the symptoms of psychosis may be better understood by linking the steps between the phenomenological experiences and social, psychological and neurobiological levels of explanation. Cognitive models of psychosis are an important link in this chain. They provide a psychological description of the phenomena from which hypotheses concerning causal processes can be derived and tested; social, individual, and neurobiological factors can then be integrated via their impact on these cognitive processes. In this paper, we set out the cognitive processes that we think lead to the formation and maintenance of the positive symptoms of psychosis and we attempt to integrate into our model research in social factors. If this model proves useful, a fuller integration with the findings of biological research will be required (Frith, 1992).

Atypical antipsychotics in the treatment of schizophrenia: systematic overview and meta-regression analysis

Abstract Objective: To develop an evidence base for recommendations on the use of atypical antipsychotics for patients with schizophrenia. Design: Systematic overview and meta-regression analyses of randomised controlled trials, as a basis for formal development of guidelines. Subjects: 12 649 patients in 52 randomised trials comparing atypical antipsychotics (amisulpride, clozapine, olanzapine, quetiapine, risperidone, and sertindole) with conventional antipsychotics (usually haloperidol or chlorpromazine) or alternative atypical antipsychotics. Main outcome measures: Overall symptom scores. Rate of drop out (as a proxy for tolerability) and of side effects, notably extrapyramidal side effects. Results: For both symptom reduction and drop out, there was substantial heterogeneity between the results of trials, including those evaluating the same atypical antipsychotic and comparator drugs. Meta-regression suggested that dose of conventional antipsychotic explained the heterogeneity. When the dose was ≤12 mg/day of haloperidol (or equivalent), atypical antipsychotics had no benefits in terms of efficacy or overall tolerability, but they still caused fewer extrapyramidal side effects. Conclusions: There is no clear evidence that atypical antipsychotics are more effective or are better tolerated than conventional antipsychotics. Conventional antipsychotics should usually be used in the initial treatment of an episode of schizophrenia unless the patient has previously not responded to these drugs or has unacceptable extrapyramidal side effects.

The List of Threatening Experiences: a subset of 12 life event categories with considerable long-term contextual threat.

In a survey of a random sample of the general population recent life events, collected and rated for long-term contextual threat according to the methods of Brown & Harris (1978), were also recorded where possible on an inventory of life event categories (Tennant & Andrews, 1977). Of the 82.5% of all events collected which were covered by the inventory, 12 of the 67 event categories accounted for 77% of life events with an aetiologicaly significant rating of marked or moderate long-term threat. Where practical and economic constraints oblige research workers to choose the inventory method, a brief list of event categories, such as the List of Threatening Experiences, is recommended in preference to much longer lists.

A cognitive model of persecutory delusions

A multifactorial model of the formation and maintenance of persecutory delusions is presented. Persecutory delusions are conceptualized as threat beliefs. The beliefs are hypothesized to arise from a search for meaning for internal or external experiences that are unusual, anomalous, or emotionally significant for the individual. The persecutory explanations formed reflect an interaction between psychotic processes, pre-existing beliefs and personality (particularly emotion), and the environment. It is proposed that the delusions are maintained by processes that lead to the receipt of confirmatory evidence and processes that prevent the processing of disconfirmatory evidence. Novel features of the model include the (non-defended) direct roles given to emotion in delusion formation, the detailed consideration of both the content and form of delusions, and the hypotheses concerning the associated emotional distress. The clinical and research implications of the model are outlined.

The National Psychiatric Morbidity surveys of Great Britain--initial findings from the household survey.

BACKGROUND This paper describes the Household Survey from the National Survey of Psychiatric Morbidity. This covered a sample drawn at random from the population of Britain, with the exception of the Highlands and Islands of Scotland. METHODS The Postcode Address file was used as the sampling frame. Nearly 13000 adults aged 16-65 were selected for interview, of whom 10108 (79.4%) were successfully interviewed. Eight per cent could not be contacted and 13% refused interview. Psychiatric assessment was carried out by lay interviewers using the CIS-R. Subjects were also screened for psychosis, and screen-positive individuals were examined by psychiatrists using SCAN. RESULTS Sixteen per cent of subjects scored above the standard cut-off of 12 on the CIS-R. The overall 1-week prevalence of neurotic disorder was 12.3% in males and 19.5% in females. Unmarried and post-marital groups had high rates of disorder, as did single parents and people living on their own. Respondents in Social Class I had notably lower rates of neurotic disorder than the remainder of the sample. Unemployment was strongly associated with disorder. Subjects living in urban areas had a higher overall prevalence, but there was no significant variation by region. Black respondents had higher rates of disorders that were entirely explained by their age, family type and social class. Individual neurotic disorders were all significantly commoner in women, with the exception of panic disorder. The 1-year prevalence of functional psychoses was 4 per 1000, with no sex difference. Alcohol and drug dependence was considerably more prevalent in men. CONCLUSIONS For the first time, the survey provides data on the prevalence and correlates of psychiatric disorder on a nationwide sample that can be used to inform equitable and effective national psychiatric services.

Epidemiology of Autism Spectrum Disorders in Adults in the Community in England

CONTEXT To our knowledge, there is no published information on the epidemiology of autism spectrum disorders (ASDs) in adults. If the prevalence of autism is increasing, rates in older adults would be expected to be lower than rates among younger adults. OBJECTIVE To estimate the prevalence and characteristics of adults with ASD living in the community in England. DESIGN A stratified, multiphase random sample was used in the third national survey of psychiatric morbidity in adults in England in 2007. Survey data were weighted to take account of study design and nonresponse so that the results were representative of the household population. SETTING General community (ie, private households) in England. PARTICIPANTS Adults (people 16 years or older). MAIN OUTCOME MEASURES Autism Diagnostic Observation Schedule, Module 4 in phase 2 validated against the Autism Diagnostic Interview-Revised and Diagnostic Interview for Social and Communication Disorders in phase 3. A 20-item subset of the Autism-Spectrum Quotient self-completion questionnaire was used in phase 1 to select respondents for phase 2. Respondents also provided information on sociodemographics and their use of mental health services. RESULTS Of 7461 adult participants who provided a complete phase 1 interview, 618 completed phase 2 diagnostic assessments. The weighted prevalence of ASD in adults was estimated to be 9.8 per 1000 (95% confidence interval, 3.0-16.5). Prevalence was not related to the respondents age. Rates were higher in men, those without educational qualifications, and those living in rented social (government-financed) housing. There was no evidence of increased use of services for mental health problems. CONCLUSIONS Conducting epidemiologic research on ASD in adults is feasible. The prevalence of ASD in this population is similar to that found in children. The lack of an association with age is consistent with there having been no increase in prevalence and with its causes being temporally constant. Adults with ASD living in the community are socially disadvantaged and tend to be unrecognized.

The predictive utility of expressed emotion in schizophrenia: an aggregate analysis.

We analysed aggregate data from 25 studies linking Expressed Emotion (EE) and schizophrenia. We had access to original data sets from 17 studies, and used published data from the remainder. This provided us with 1346 cases from around the world. The association of EE with relapse was overwhelming, and was maintained whatever the geographical location. The predictive capacity of EE was virtually identical in men and women. While high contact with a high EE relative increased the risk of relapse, the opposite was true in low EE households. Medication and EE were independently related to relapse, and thus EE status has no bearing on the decision to prescribe. Our findings were confirmed using log-linear analysis.

The influence of age and sex on the prevalence of depressive conditions: Report from the National Survey of Psychiatric Morbidity

Women are consistently reported to have a greater prevalence of depressive disorders than men. The reason for this is unclear, and is as likely to be social as biological. There is some evidence that the excess of depression is greater during womens reproductive lives. Data from the National Survey of Psychiatric Morbidity were used to test the hypothesis that the excess disappeared in the post-menopausal years and that obvious social explanations for this were inadequate. Subjects (n = 9792) from a random sample of the British population provided data for the analysis. Lay interviewers using the CIS-R carried out psychiatric assessment. Subjects with ICD-10 depressive episode or mixed anxiety/depression were compared with the remainder. Social variables that were likely to contribute to a post-menopausal decline in depressive disorders were controlled in logistic regression analyses. There was a clear reversal of the sex difference in prevalence of depression in those over age 55. This could not be explained in terms of differential effects of marital status, childcare, or employment status. This large and representative survey adds considerably to the increasingly held view that the sex difference in prevalence of depression is less apparent in later middle age. This may be linked to the menopause, and our attempts to explain it in terms of obvious conditions among social variables were not successful. More specific studies are required to clarify the finding.

Reasoning, emotions, and delusional conviction in psychosis

The aim of the study was to elucidate the factors contributing to the severity and persistence of delusional conviction. One hundred participants with current delusions, recruited for a treatment trial of psychological therapy (PRP trial), were assessed at baseline on measures of reasoning, emotions, and dimensions of delusional experience. Reasoning biases (belief inflexibility, jumping to conclusions, and extreme responding) were found to be present in one half of the sample. The hypothesis was confirmed that reasoning biases would be related to delusional conviction. There was evidence that belief inflexibility mediated the relationship between jumping to conclusions and delusional conviction. Emotional states were not associated with the reasoning processes investigated. Anxiety, but not depression, made an independent contribution to delusional conviction.

Psychological treatments in schizophrenia: II. Meta-analyses of randomized controlled trials of social skills training and cognitive remediation.

BACKGROUND Social skills training and cognitive remediation are psychological techniques with considerable face validity for the treatment of negative symptoms of schizophrenia and their consequences. This paper provides a meta-analytical review of these treatments. It includes an appreciable number of randomized controlled trials, using comparisons against both standard care and other active interventions. However, the assessment of particular outcomes sometimes had to be based on single studies. METHOD A detailed search strategy was used to identify randomized controlled trials of social skills training and cognitive remediation, primarily employing electronic databases. Randomized controlled trials (RCTs) that met predefined criteria were then subjected to meta-analysis on a variety of outcome measures. RESULTS There was no clear evidence for any benefits of social skills training on relapse rate, global adjustment, social functioning, quality of life or treatment compliance. Cognitive remediation had no benefit on attention, verbal memory, visual memory, planning, cognitive flexibility or mental state. CONCLUSIONS Social skills training and cognitive remediation do not appear to confer reliable benefits for patients with schizophrenia and cannot be recommended for clinical practice.