Biomedical subjects

J van Os

Publications and source records attributed to J van Os.

At least 37 records · Page 2Linked to original sources

PubMed2004

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.

Adolescent↗

PubMed2004

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.

Cross-Sectional Studies↗

PubMed2004

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.

Adult↗

PubMed2004

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.

Adolescent↗

PubMed2004

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.

Acute Disease↗

PubMed2004

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.

Adult↗

PubMed2004

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.

Adult↗

PubMed2004

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.

Adult↗

PubMed2004

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.

Adolescent↗

PubMed2004

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.

Adult↗

PubMed2003

Age-dependence of Schneiderian psychotic symptoms in bipolar patients.

Psychotic symptoms frequently occur in bipolar disorder, especially in younger patients. However, whether the association with younger age also extends to psychotic symptoms that have traditionally been associated with schizophrenia, such as Schneiderian first-rank symptoms (FRSs), is unclear. This study examined FRSs in bipolar I patients and their relationship to age and gender. The sample comprised 103 consecutive inpatients who met DSM IV criteria for bipolar disorder, manic or mixed. FRSs were rated with the Scale for the Assessment of Positive Symptoms (SAPS). Interaction between FRSs and gender and FRSs and age was assessed using logistic regression. A high rate of FRSs in manic and mixed patients was found with a higher frequency in men (31%) than in women (14%; P=0.038). A monotonic increase in the association between FRSs and younger age was apparent (odds ratios (OR) over five levels: 1.42; 1.00-2.01). These results confirm previous findings that FRSs are not specific to schizophrenia and suggest in addition that a dimension of nuclear psychotic experiences of developmental origin extends across categorically defined psychotic disorders.

Adolescent↗

PubMed2003

How psychotic are individuals with non-psychotic disorders?

BACKGROUND: The objective of this study was to compare, using a self-report questionnaire, the dimensions of psychosis across different patient groups in a community mental health service (CMHS) and in non-patients in the general population. METHODS: The Community Assessment of Psychic Experiences (CAPE) is a 40-item self-report instrument with positive, negative and depressive symptom dimensions. Seven hundred and sixty-two patients and 647 subjects in the general population filled in the CAPE. In 555 of the 762 patients, a DSM-IV diagnosis was made. The following DSM-IV categories were used in the analyses: 1. Schizophrenia and Other Psychotic Disorders (n = 72), 2. Mood Disorders (n = 214), 3. Anxiety Disorders (n = 129). The patient and non-patient groups were compared on the three dimensions of the CAPE using multivariate regression analysis. RESULTS: The patient groups scored significantly higher on the positive, negative and depressive dimensions than the non-patients. Patients with psychotic disorders had the greatest difference in positive psychosis items compared to non-patients (beta = 0.94, 95 % CI: 0.7-1.18), whereas patients with mood and anxiety disorders had the highest depressive symptom scores, and positive symptom scores that were intermediate to that of non-patients and patients with psychotic disorders (mood disorders: beta = 0.53, 95 % CI: 0.39-0.68; anxiety disorders: beta = 0.22, 95 % CI: 0.04-0.39). The CAPE distress score adjusted for the corresponding frequency score was not significantly different between the patient groups, but compared to the general population, patient status did contribute significantly to the level of distress. DISCUSSION: Patients with anxiety and mood disorders had elevated scores on positive psychosis items, indicating that expression of psychosis in non-psychotic disorders is common. The finding of elevated scores of the patient groups on all three dimensions compared to non-patients suggests that the psychopathology associated with psychotic disorders varies quantitatively across DSM-IV categories.

Adult↗

PubMed2003

Can cognitive deficits explain differential sensitivity to life events in psychosis?

BACKGROUND: Life events (LE) have been found to influence the onset and course of psychotic disorders. It has been suggested that LE have their effect by increasing underlying sensitivity to daily life stress, a reported vulnerability marker for psychosis. As increased stress-sensitivity and cognitive impairments have been shown to be negatively associated with each other in patient populations, it is attractive to hypothesise that the impact of LE on sensitivity to daily stress is modified by the degree of cognitive impairment, higher levels of cognitive impairment giving rise to reduced impact of LE on daily life stress-sensitivity. METHODS: Patients with psychotic illness (n = 42) were studied with a) a standard battery of neuropsychological tests to assess cognitive functioning, b) the Experience Sampling Method (a structured diary technique assessing current context and mood in daily life) to assess (i) appraised subjective stress related to daily events and activities, and (ii) emotional reactivity conceptualised as changes in both negative affect (NA) and positive affect (PA), and c) the Brown and Harris Life Event and Difficulties Schedule to assess LE over the last year. RESULTS: Multilevel regression analyses showed that a prior history of LE increased the sensitivity for daily life stress in subjects with the best performance on the cognitive tests. CONCLUSIONS: Subjects with cognitive impairments, who already were shown to have lower levels of sensitivity to daily life stress (Myin Germeys et al. 2002), may additionally be less reactive to prior exposure to LE. This result fits with the notion of separate affective and cognitive pathways of symptom formation in psychosis, the cognitive pathway being characterised by severe cognitive deficits and the affective pathway by increased levels of stress-sensitivity associated with prior exposure to LE.

Adaptation, Psychological↗

PubMed2003

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.

Adult↗

PubMed2003

Self-reported psychotic experiences in the general population: a valid screening tool for DSM-III-R psychotic disorders?

OBJECTIVE: To examine the diagnostic value of self-reported psychotic-like experiences for DSM-III-R psychotic disorders. METHOD: A general population sample of 7076 subjects aged 18-64 years was interviewed with the Composite International Diagnostic Interview (CIDI) and, if there was evidence of psychotic experiences, the Structured Clinical Interview for DSM-III-R. RESULTS: The probability of having a psychotic disorder increased in a dose-response fashion with the level of self-reported psychotic experiences, but individual CIDI psychotic experience ratings had relatively low post-test probabilities (PPs) (range: 5.1-26.5%). However, limiting the sample to individuals who had been in contact with mental health services substantially improved PPs (range: 13.3-43.1%). CONCLUSION: Screening for psychosis in the population carries a high risk of stigmatization in false-positive cases and violation of the right 'not to know' in true-positive cases. However, in mental health care users, self-reported psychotic experiences may be a useful screening tool in individuals who have already developed help-seeking.

Adult↗

PubMed2003

Cerebral tissue alterations and daily life stress experience in psychosis.

OBJECTIVE: To examine whether the total volumes of cerebrospinal fluid (CSF), cerebral grey matter and white matter were correlated with the experience of environmental stress in daily life situations. METHOD: Twenty-seven patients with psychosis underwent magnetic resonance imaging scanning and a random time-sampling self-assessment technique (Experience Sampling Method) to determine subjective daily life stress experiences. Total cerebral tissue volumes were derived from an automated segmentation procedure. RESULTS: CSF volume was positively associated with daily life event-related stress (beta=0.016, P=0.002), while the association with total white matter was negative (beta=-0.013, P=0.005). The effects were independent of each other and of total cerebral volume and other confounders. No large or significant association was found with grey matter volume. CONCLUSION: Subjective stress experience in daily life is associated with increased CSF and reduced white matter volumes in patients with psychosis, suggesting functional significance of these cerebral measures.

Adolescent↗

PubMed2003

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.

Adolescent↗

PubMed2003

Discrimination and delusional ideation.

BACKGROUND: In the UK and The Netherlands, people with high rates of psychosis are chronically exposed to discrimination. AIMS: To test whether perceived discrimination is associated longitudinally with onset of psychosis. METHOD: A 3-year prospective study of cohorts with no history of psychosis and differential rates of reported discrimination on the basis of age, gender, disability, appearance, skin colour or ethnicity and sexual orientation was conducted in the Dutch general population (n=4076). The main outcome was onset of psychotic symptoms (delusions and hallucinations). RESULTS: The rate of delusional ideation was 0.5% (n=19) in those who did not report discrimination, 0.9% (n=4) in those who reported discrimination in one domain, and 2.7% (n=3) in those who reported discrimination in more than one domain (exact P=0.027). This association remained after adjustment for possible confounders. No association was found between baseline discrimination and onset of hallucinatory experiences. CONCLUSIONS: Perceived discrimination may induce delusional ideation and thus contribute to the high observed rates of psychotic disorder in exposed minority populations.

Adolescent↗