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J Van Os

Publications and source records attributed to J Van Os.

At least 37 records · Page 2Linked to original sources
PubMed1999

A comparison of the utility of dimensional and categorical representations of psychosis. UK700 Group.

BACKGROUND: The usefulness of any diagnostic scheme is directly related to its ability to provide clinically useful information on need for care. In this study, the clinical usefulness of dimensional and categorical representations of psychotic psychopathology were compared. METHOD: A total of 706 patients aged 16-65 years with chronic psychosis were recruited. Psychopathology was measured with the Comprehensive Psychopathological Rating Scale (CPRS). Lifetime RDC, DSM-III-R, and ICD-10 diagnoses and ratings of lifetime psychopathology were made using OPCRIT. Other clinical measures included: (i) need for care; (ii) quality of life; (iii) social disability; (iv) satisfaction with services; (v) abnormal movements; (vi) brief neuropsychological screen; and (vii) over the last 2 years--illness course, symptom severity, employment, medication use, self-harm, time in hospital and living independently. RESULTS: Principal component factor analysis of the 65 CPRS items on cross-sectional psychopathology yielded four dimensions of positive, negative, depressive and manic symptoms. Regression models comparing the relative contributions of dimensional and categorical representations of psychopathology with clinical measures consistently indicated strong and significant effects of psychopathological dimensions over and above any effect of their categorical counterparts, whereas the reverse did not hold. The effect of psychopathological dimensions was mostly cumulative: high ratings on more than one dimension increased the contribution to the clinical measures in a dose-response fashion. Similar results were obtained with psychopathological dimensions derived from lifetime psychopathology ratings using the OCCPI. CONCLUSIONS: A dimensional approach towards classification of psychotic illness offers important clinical advantages.

Adolescent↗
PubMed1999

Early risk factors and adult person--environment relationships in affective disorder.

BACKGROUND: Lower cognitive ability, higher neuroticism and symptoms of anxiety and depression in childhood predict non-psychotic disorder in adulthood. This study examined whether these early risk factors act by modifying relationships with life events close to disease onset in adulthood. METHODS: Childhood measures of neuroticism (N) (including maternal N), cognitive ability (CA) and symptoms of anxiety and depression were measured in a national British birth cohort of 5362 individuals born in the week 3-9 March, 1946. At ages 36 and 43 years, mental state examinations were carried out by trained interviewers, and subjects were asked about the occurrence of stressful life events in the previous year (SLE). RESULTS: The effect of aggregated SLEs on mental health was greater in women, in individuals with higher childhood N and poorer childhood mental health. Higher maternal N was also associated with greater sensitivity to SLEs, independent of subject's N, suggesting possible familial transmission of vulnerability. In addition, higher childhood N predicted, independent of later mental health, greater likelihood of reported exposure to SLEs. In general, individuals with higher childhood CA also reported more SLEs. CONCLUSIONS: The results suggest that early risk factors for affective disorder exert effects by modifying person-environment relationships close to onset of adult symptoms. Sensitivity to life events may be transmitted from parents to offspring; psychopathological continuity over the life-span may be explained in part by continuity of altered stress sensitivity.

Adaptation, Psychological↗
PubMed1998

Congenital dermatoglyphic malformations in severe bipolar disorder.

Dermatoglyphic alterations may be the result of early prenatal disturbances thought to be implicated in the aetiology of psychiatric illness. In order to test this hypothesis in the particular case of bipolar disorder, we assessed two congenital dermatoglyphic malformations (ridge dissociation (RD) and abnormal features (AF)) and two metric dermatoglyphic traits (total finger ridge count (TFRC) and total a-b ridge count (TABRC)) in a sample of 118 patients with chronic DSM-III-R bipolar illness, and 216 healthy controls. Bipolar cases showed a significant excess of RD and AF (OR = 2.80; 95% CI: 2.31-3.38) when compared with controls. In the cases, the presence of anomalies was associated with earlier age of onset. No differences were found for TFRC and TABRC. No associations were found with sex or familial morbid risk of psychiatric disorders. Our findings add further weight to the suggestion that early developmental disruption is a risk factor for later bipolar disorder.

Bipolar Disorder↗
PubMed1998

Risk factors for onset and persistence of psychosis.

Clinical practice, training and evaluation of treatment in the functional psychoses continues to be carried out mostly along the traditional line of separation by diagnostic entity. However, the combined evidence from research on risk factors for onset and for persistence of psychotic illness indicates quantitative, but not qualitative, differences between categories of schizophrenia and affective psychosis. "Developmental" factors, such as childhood dysfunction, increased cerebral ventricle size and familial morbid risk of schizophrenia operate preferentially, though not specifically, at that end of the psychopathological spectrum characterised by a preponderance of negative features. On the other hand, "social" factors, such as ethnic group, adverse life events and familial morbid risk of affective disorder have a larger impact at the end associated with predominance of affective features. Heterogeneity in the functional psychoses may thus be best conceived as two discrete effects operating at different ends of a continuous psychopathological spectrum. The use of highly reliable but arbitrary diagnostic categories may introduce serious bias in aetiological and treatment research. Evidence supporting the validity of a model of shared risk factors for continuous characteristics needs to be further elaborated and incorporated into our concepts of psychotic illness.

Affective Disorders, Psychotic↗
PubMed1998

Shared social environment and psychiatric disorder: a multilevel analysis of individual and ecological effects.

We examined associations, in terms of relative and population-attributable risks, between shared social environment at the neighbourhood level and (1) treated incidence of non-psychotic, non-organic disorders, and (2) subsequent level of service consumption. The multilevel analysis used linked records of all individuals in contact for the first time with any catchment area mental health service for non-psychotic, non-organic disorder over various specified time periods between 1981 and 1995. Socioeconomic indicators of 36 neighbourhoods in the city of Maastricht yielded a multivariately defined neighbourhood deprivation score. There were significant linear trends in the association between level of deprivation and treated incidence, especially in the population under 35 years of age (adjusted rate ratio for linear trend 1.17, 95% confident interval 1.11-1.23), who constituted around half of the patient population. The fraction of the incidence of psychiatric disorder attributable to deprivation was 17.8%. Multilevel analyses of rates of a second cohort, with cases divided according to level of service use over a standardised follow-up of 5 years after first contact with psychiatric services, revealed that the effect of deprivation scores on rates declined with intensity of out-patient service use, but increased with level of in-patient use. Up to 50% of in-patient episodes in this group could be attributed to neighbourhood level of deprivation. The increase in risk conferred by neighbourhood deprivation remained after adjustment for the individual-level equivalent. The findings therefore suggest that elements in the shared social environment influence both incidence and severity of non-psychotic, non-organic disorders, over and above any individual-level effect.

Adolescent↗
PubMed1998

A survey of delusional ideation in primary-care patients.

BACKGROUND: To assess the prevalence of delusional ideas in primary-care patients. METHOD: A survey was carried out with the Aquitaine Sentinel Network of general practitioners (GPs). Consecutive practice attenders were invited to complete the Peters et al. Delusional Inventory (PDI-21) self-report questionnaire, designed to measure delusional ideation in the normal population. GPs, blind to the questionnaire results, provided information on patients' psychiatric history. RESULTS: Of the 1053 attenders included in the survey, 348 (35%) had a lifetime history of psychiatric disorder, of whom 20 (2%) had a history of broadly defined psychotic disorder. The self-report questionnaire was completed by 790 patients. The range of individual PDI-21 item endorsement in subjects with no psychiatric history varied between 5 and 70%, suggesting that delusional ideation is a dimensional phenomenon lying on a continuum with normality. The main discriminative items between psychotic and non-psychotic patients were those exploring persecutory (OR = 15.2, 95% CI 4.3-53.7), mystic (OR = 6.4, 95% CI 1.9-22.4) and guilt (OR = 5.8, 95% CI 1.5-23.2) ideas. CONCLUSIONS: This survey demonstrates that questions that explore delusions and hallucinations are well-accepted by most primary-care patients. More research is needed on psychotic disorders in primary-care settings to improving early identification of these disorders.

Adolescent↗
PubMed1998

Urbanization and psychosis: a study of 1942-1978 birth cohorts in The Netherlands.

BACKGROUND: Urban birth is associated with later schizophrenia. This study examined whether this finding is diagnosis-specific and which individuals are most at risk. METHODS: All live births recorded between 1942 and 1978 in any of the 646 Dutch municipalities were followed-up through the National Psychiatric Case Register for first psychiatric admission for psychosis between 1970 and 1992 (N = 42115). RESULTS: Urban birth was linearly associated with later schizophrenia (incidence rate ratio linear trend (IRR), 1.39; 95% confidence interval (95% CI), 1.36-1.42), affective psychosis (IRR, 1.18; 95% CI, 1.15-1.21) and other psychosis (IRR, 1.27; 95% CI, 1.24-1.30). Individuals born in the highest category of the three-level urban exposure were around twice as likely to develop schizophrenia. Associations were stronger for men and for individuals with early age of onset. The effect of urban birth was also stronger in the more recent birth cohorts. CONCLUSIONS: There are quantitative differences between diagnostic categories in the strength of the association between urban birth and later psychiatric disorder. High rates of psychosis in urban areas may be the result of environmental factors associated with urbanization, the effect of which appears to be increasing over successive generations.

Adult↗
PubMed1998

Predictors of outcome in schizophrenia.

Several factors have been reported to be associated with poor outcome in psychosis. A prospective study was conducted to identify and subsequently assess the relative prognostic value of factors that might assist in the earlier identification of patients likely to have a poor outcome. The results confirmed that certain factors, including male gender, family history of schizophrenia, structural brain abnormalities, absence of adverse life events, and tardive dyskinesia, were indeed associated with poor outcome.

Adult↗
PubMed1997

Genetic variation of the 5-HT2A receptor gene and bipolar affective disorder.

Abnormalities of the serotonergic system have classically been associated with the origin of affective disorders through the biochemical action of therapeutic agents and their role in affective and perceptual states. In the present study, we hypothesized that genetic variation in the 5-hydroxytryptamine (serotonin) type 2A (5-HT2A) receptor gene (HTR2A) might have an effect on the aetiology of bipolar affective disorder. Four different polymorphisms in the HTR2A gene were studied in 88 patients with bipolar affective disorder and 113 healthy controls, all of Spanish origin. No significant association was observed between any of the four polymorphisms at the HTR2A locus, whether tested individually or as haplotypes, and bipolar affective disorder. The lack of association suggests that HTR2A is not a major risk factor for bipolar affective disorder.

Bipolar Disorder↗
PubMed1997

Psychopathological syndromes and familial morbid risk of psychosis.

BACKGROUND: Familial liability in the functional psychoses had traditionally been examined by comparing mutually exclusive diagnostic categories. This study examines overlapping psychopathological dimensions in relation to familial morbid risk of psychosis. METHOD: We tested for associations between seven factor-analysis derived psychopathological dimensions and familial morbid risk of psychosis, in a sample of 150 patients with recent-onset functional psychosis and 548 of their first-degree relatives. RESULTS: A syndrome characterised by affective blunting and insidious and early onset of illness, non-specifically predicted psychosis in the first-degree relatives, whereas a manic syndrome specifically predicted affective psychosis in the relatives. No other main effects were observed, but there were interactions with proband diagnosis: a syndrome characterised by bizarre behaviour, inappropriate affect, catatonia and poor rapport predicted psychosis in relatives of schizophrenic probands, and a syndrome of depressive: symptoms predicted psychosis in relatives of schizoaffective probands. Positive symptoms were not associated with illness in the relatives. CONCLUSIONS: Genetic effects in the functional psychoses may comprise non-specific components that canalise a general, early-onset, affective blunting phenotype and several other, more specific, influences on phenotypic variation.

Adult↗
PubMed1996

Parasuicide in Camberwell-ethnic differences.

Over a 6-month period, this study compared referral rates amongst different ethnic groups to an inner city deliberate self-harm (DSH) team, using native British (in the remainder of this paper referred to as whites) as standard and age-standardized referral ratios as the measure of effect. Indian female rates were 2.6 times those of whites. Amongst United Kingdom born Indian females, (crude) rates were 7.8 times those of United Kingdom born white females. Unemployment was associated with a 9 times increased referral rate amongst whites and a 3 times increased referral rate amongst ethnic minorities, suggesting that ethnicity modifies the association between unemployment and DSH rates. This study suggested that ethnic minority and white DSH differ in important respects; DSH teams serving multicultural communities may need to develop special expertise to meet the needs of minority ethnic groups.

Adolescent↗
PubMed1994

Cerebral ventricle dimensions as risk factors for schizophrenia and affective psychosis: an epidemiological approach to analysis.

A case-control study was undertaken of volumetric computerized tomographic scan measures in 216 consecutive admissions for functional psychosis and 67 healthy community controls. Odds ratio analysis demonstrated significant linear trends in the association between increasing lateral and third ventricle volumes, and both RDC schizophrenia (N = 121) and schizo-affective disorder (N = 41); cases were consistently associated with larger volumes than controls. There was an association between larger third, but not lateral, ventricle size in affective psychoses (N = 54). These associations were statistically independent of intracranial volume, sex, social class and ethnicity, factors which were significantly associated with ventricular measures in the controls. There was no evidence of a threshold corresponding to the notion of normal versus enlarged ventricles. Within the schizophrenia group, there were no large or significant associations between ventricle dimensions and age at onset, duration of illness or pre-morbid social functioning. Neither obstetric complications nor a family history of schizophrenia or other psychiatric illness was associated with large ventricles in these cases.

Adolescent↗
PubMed1994

Analysis of the conserved Asp(114) residue of the dopamine D2 receptor in schizophrenic patients.

The factors that influence response to antipsychotics treatment in chlorpromazine remain difficult to delineate but are thought to include genetic factors. Site-directed mutagenesis studies have demonstrated that substitution of the conserved residues Asp(113) to an Asn or Glu greatly reduces the binding affinity of propranolol in the beta-adrenergic receptor and the substitution of an Asp(114) has similar effects in the dopamine D2 receptor. In this study we have found the Asp(114) in the dopamine D2 receptor to be unaltered in 72 unrelated schizophrenic individuals including 12 patients classified according to their response to chlorpromazine.

Aspartic Acid↗
PubMedDate not supplied

No association between RFLPs at the porphobilinogen deaminase gene and schizophrenia.

An association study of restriction fragment length polymorphisms (RFLPs) in the porphobilinogen deaminase (PBGD) gene and schizophrenia was conducted. RFLPs detected by MspI, PstI, ApaLI and BstNI in intron 1 of the gene were studied in 49 patients and 79 controls. There were no significant differences between the groups in allele frequencies, genotype counts or haplotype distribution.

Adult↗
PubMedDate not supplied

Maternal exposure to influenza and risk of schizophrenia: a 22 year study from The Netherlands.

We investigated any effect of prenatal exposure to influenza during gestation on subsequent risk of schizophrenia using a national sample from The Netherlands. Dates of births of all Dutch-born schizophrenia (ICD-9) patients (n = 10,630) admitted to hospitals for the first time between 1970 and 1992 were examined in relation to the occurrence of influenza epidemics between 1947 and 1969. As a measure of prevalence of influenza, the number of deaths from influenza per month in The Netherlands was used. A Poisson regression analysis revealed that an increase in the prevalence of influenza 3 months prior to birth was followed by an increase in births of preschizophrenics, although this fell outside statistical significance (p = .11). However, the effect became marked in typical schizophrenics (n = 4726), but not in less typical cases (n = 5389). For typical schizophrenics, the parameter estimate derived from the regression model indicates that there was a 10% increase (95% confidence interval: -1 to 22%) in preschizophrenic births for every 500 deaths from influenza 3 months before birth.

Adult↗