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Biomedical subjects

J van Os

Publications and source records attributed to J van Os.

At least 91 records · Page 5Linked to original sources
PubMed1999

Self-reported psychosis-like symptoms and the continuum of psychosis.

BACKGROUND: It has been suggested that psychotic symptoms may be distributed along a continuum that extends from normality through depressive states to schizophrenia with increasing level of severity. This study examined the hypothesis that the severity of positive psychotic symptoms increases from normality, through depression/anxiety states to clinical psychosis. METHODS: Consecutive general practice attenders completed a self-report questionnaire of 24 items of delusional ideation and hallucinatory experiences and the GHQ-12. The following groups were compared: (1) subjects with a diagnosis of psychosis (n = 57), (2) GHQ cases (n = 245), and (3) GHQ non-cases (n = 378). RESULTS: Quantitative differences were apparent in the great majority of items on delusional ideation and hallucinatory experiences, in that normals scored lowest, psychosis patients scored highest and GHQ cases scored in between. This pattern of differences was apparent for all dimensions of psychosis-like experiences, including the more "schizophrenic" ones, with the exception of Grandiosity (GHQ cases similar to normals) and Paranormal Beliefs (no differences between the three groups). CONCLUSIONS: Similar to findings in aetiological research, phenotypic differences between normal controls, patients with anxiety/depression and patients with psychosis appear quantitative rather than qualitative for core dimensions of psychosis.

Adult↗
PubMed1999

To what extent does symptomatic improvement result in better outcome in psychotic illness? UK700 Group.

BACKGROUND: The effectiveness of therapeutic interventions in psychosis is increasingly reported in terms of reductions in different symptom dimensions. It remains unclear, however, to what degree such symptomatic changes are accompanied by improvement in other measures such as service use, quality of life, and needs for care. METHODS: A sample of 708 patients with chronic psychotic illness was assessed on three occasions over 2 years (baseline, year 1 and year 2). A multilevel analysis was conducted to examine to what degree reduction in psychopathological scores derived from factor analysis of the Comprehensive Psychopathological Rating Scale (CPRS), was associated with improvement in service use, disability, subjective outcomes and measures of self-harm. RESULTS: Reduction in positive, negative, depressive and manic symptoms over the study period were all independently associated with lessening of social disability. Reduction in negative symptoms, and to a lesser extent in positive and manic symptoms, was associated with less time in hospital and more time living independently, whereas changes in positive and manic symptoms resulted in fewer admissions. Subjective outcomes such as improvement in quality of life, perceived needs for care and dissatisfaction with services showed the strongest associations with reduction in depressive symptoms. Reduction in positive symptoms was associated with decreased likelihood of parasuicide. Results did not differ according to diagnostic category. CONCLUSION: The findings suggest that changes in distinct psychopathological dimensions independently and differentially influence outcome. Therapeutic interventions aimed at reducing symptoms of more than one dimension are likely to have more widespread effects.

Adolescent↗
PubMed1999

Urbanization and risk for schizophrenia: does the effect operate before or around the time of illness onset?

BACKGROUND: Higher level of urbanicity of place of birth and of place of residence at the time of illness onset has been shown to increase the risk for adult schizophrenia. However, because urban birth and urban residence are strongly correlated, no conclusions can be drawn about the timing of the risk-increasing effect. The current study discriminated between any effect of urbanization before and around the time of illness onset. METHODS: All individuals born between 1972 and 1978 were followed up through the Dutch National Psychiatric Case Register for first admission for schizophrenia until 1995 (maximum age 23 years). Exposure status was defined by a combination of place of birth and place of residence at the time of illness onset in the three most densely populated provinces of the Netherlands (the 'Randstad', exposed) or in all other areas (the 'non-Randstad', non-exposed). The risk for schizophrenia was examined in four different exposure groups: non-exposed born and non-exposed resident (NbNr, reference category), non-exposed born and exposed resident (NbEr), exposed born and non-exposed resident (EbNr) and exposed born and exposed resident (EbEr). RESULTS: The greatest risk for schizophrenia was found in the EbNR group, without evidence for any additive effect of urban residence (rate ratio (RR) for narrow schizophrenia in EbNr group, 2.05 (95 % CI 1.18-3-57); in EbEr group, 1.96 (95% CI, 1.55-2.46)). Individuals who were not exposed at birth, but became so later in life, were not at increased risk of developing schizophrenia (RR for narrow schizophrenia in NbEr group, 0.79 (0.46-1.36)). CONCLUSION: The results suggest that environmental factors associated with urbanization increase the risk for schizophrenia before rather than around the time of illness onset.

Adolescent↗
PubMed1999

Tardive dyskinesia in psychosis: are women really more at risk? UK700 Group.

It is commonly held that women are more at risk of developing tardive dyskinesia (TD). However, recent evidence suggests that this may only be the case in samples of older patients, men being more at risk in the younger age groups. Abnormal movements were measured with the Abnormal Involuntary Movement Scale (AIMS) in a sample of 706 chronic psychotic patients aged not older than 65 years (median age 36 years). Female gender was associated with a lower risk of TD (OR, 0.5; 95% CI, 0.3-0.7). The effect of gender was independent of other risk factors such as older age, severity of negative symptoms and exposure to antipsychotic medication in the previous 2 years. There was no evidence that the effect of these risk factors differed between the sexes. In samples of relatively young patients with chronic psychotic illness, who typically represent the majority of patients in community programmes for the severely mentally ill, men are more at risk of TD than women.

Adult↗
PubMed1999

Suicidality and substance misuse in first-admitted subjects with psychotic disorder.

OBJECTIVE: The aim of this study was to examine the links between suicidality and substance misuse (abuse or dependence) in subjects with early psychosis. METHOD: Data were collected on a sample of first-admitted subjects with psychosis (n=64). RESULTS: More than 1 in 4 patients had a history of parasuicide, and more than 1 in 10 patients were referred to the psychiatric hospital after such an act. Parasuicide was more frequent in subjects with a history of drug misuse (OR=4, 95% CI= 1.1-14.0, P=0.03), and especially of polysubstance use (OR=6.6, 95% CI=1.2-34.7, P=0.03). CONCLUSION: The association between substance misuse and suicidality found in subjects with psychosis is similar to that which exists in the general population. Since early psychosis is a high-risk period for substance misuse, subjects with incipient psychosis may be especially vulnerable to the devastating consequences of drug use with regard to increased risk of suicide.

Adolescent↗
PubMed1998

Characteristics of early- and late-diagnosed schizophrenia: implications for first-episode studies.

First-episode studies of schizophrenia are being carried out in many places. However, previous work has suggested that only half of the patients with schizophrenia receive the diagnosis in the initial stages of the illness. We examined whether cases of early- and late-diagnosed schizophrenia differed with respect to key sociodemographic characteristics and indicators of service use that might bias first-episode studies. Individuals who (i) presented for the first time between 1983 and 1993 to psychiatric services in a defined urban area with a cumulative mental health case register; and (ii) received a diagnosis of schizophrenia at least once during their mental health career were identified (n = 186). This sample was divided into those who received the diagnosis of schizophrenia for the first time within the first year of service contact (early-diagnosed schizophrenia; EDS), and those who received it for the first time after the first year of service contact (late-diagnosed schizophrenia; LDS). The 10-year incidence of EDS and LDS were 10.4 and 7.0 per 100,000 person-years, respectively. EDS and LDS did not differ in their pattern of association with sex, single marital status and higher levels of neighbourhood socioeconomic deprivation. However, EDS was more incident in the higher age groups, and the level of service use was higher for EDS cases in the first years of contact with mental health services, with LDS cases gradually catching up and exceeding EDS service use later in the illness course. Although differences between EDS and LDS were few, studies of patients with schizophrenia in the 'first' episode are likely to be most representative if patients who receive the diagnosis for the first time after previous episodes of care for non-schizophrenic episodes are also included.

Adult↗
PubMed1998

The ecogenetics of schizophrenia: a review.

Schizophrenia is generally thought to arise as a result of interactions between genetic vulnerability and environmental risk factors. However, research methods to actually investigate the pattern of hypothesized interactions have only recently been developed. In this article, we review the evidence that genes increase the risk for schizophrenia by making individuals more sensitive to environmental risk factors (genotype-environment interaction), or by making individuals more likely to select high-risk environments (genotype-environment correlation). It is likely that at least some of the impact of genes on the occurrence of schizophrenia is mediated through (sensitivity for) environmental risk factors such as a dysfunctional early family rearing environment, cannabis, viral infections, complications of birth and pregnancy, stressful life events and unknown environmental risk factors associated with urban birth or residence and membership of certain ethnic groups. With the advent of molecular genetics, further knowledge about possible genotype-environment interactions is urgently required in order to develop and improve strategies for the prevention and early treatment of schizophrenia.

Disease Susceptibility↗
PubMed1998

Is early adulthood a critical developmental stage for psychosis proneness? A survey of delusional ideation in normal subjects.

It has been hypothesized that late adolescence and early adulthood might be a brain developmental stage favoring the clinical expression of psychotic symptoms in psychiatric or neurological diseases. The aim of the present survey was to examine the relationship between age and delusional ideation in a sample of subjects with no psychiatric disorder. The survey was carried out with the Aquitaine Sentinel Network of general practitioners. Consecutive practice attenders were invited to complete the PDI-21 (Peters Delusional Inventory 21 items), a self-report questionnaire designed to measure delusional ideation in the normal population. The study concerned 444 patients who had no lifetime history of psychiatric disorder and who completed the PDI-21. A principal component analysis of the PDI-21 items was performed in order to identify delusional dimensions. An age-related decrease in the likelihood to report delusional ideas was found, younger subjects scoring higher on most dimensions of delusional ideation, such as 'persecution', 'thought disturbance', 'grandiosity' and 'paranormal beliefs'. 'Religiosity' was the only dimension positively associated with age. The results suggest that there may be a physiological neurodevelopmental stage favouring the expression of psychosis proneness in normal subjects, and support the hypothesis that the association between age and positive psychotic symptoms in functional and organic psychoses may be linked to the interaction between normal brain maturational processes and cerebral abnormalities involved in the aetiology of functional and organic psychoses.

Adolescent↗
PubMed1998

Obstetric complications and familial morbid risk of psychiatric disorders.

Obstetric complications (OCs) have been found to occur in higher frequency in patients with schizophrenia. One explanation for this finding is that the genes that contribute to the schizophrenia phenotype also influence the likelihood to experience OCs. If this were true, morbid risk of psychiatric illness should be higher in the first-degree relatives of both schizophrenic and control probands exposed to OCs, compared to probands not exposed to OCs. We set out to test this hypothesis. Information on OCs, blind to family history of psychiatric disorder, was collected retrospectively through maternal interview in 151 psychotic patients and 100 controls. Family history (FH) in relatives of cases (n = 600) and controls (n = 461) was assessed with the FH-RDC and through personal interviews. Tests for associations between family history and OCs were conducted using Cox proportional hazard regression. In the cases, familial morbid risk of affective disorder was greater in those with a history of OCs (hazard ratio (HR) = 1.9, P = 0.007). Analyses examining individual complications revealed associations between FH of affective disorder and pre-eclampsia (HR = 2.9, P = 0.003) and FH of affective disorder and breech presentation (HR = 2.8, P = 0.02), especially when family history in the relatives was confined to affective illness in the mother (HR pre-eclampsia = 4.4, P = 0.009; HR breech-presentation = 4.2, P = 0.008). In controls, affective illness in the mother was not only associated with breech presentation (HR = 7.0, P = 0.01) and pre-eclampsia (HR = 4.4, P = 0.03) but also with other complications. Familial morbid risk of schizophrenia and related psychoses was not associated with OCs. The positive associations between OCs and familial morbid risk of affective disorder suggest that the factors that contribute to familial aggregation of affective symptoms in psychotic patients also influence the likelihood to experience OCs. Although the proportion of OCs that could be attributed to these factors was very small, part of the relationship between family history of affective disorder and psychosis may be mediated by OCs.

Age of Onset↗
PubMed1998

Prenatal exposure to maternal stress and subsequent schizophrenia. The May 1940 invasion of The Netherlands.

BACKGROUND: It has been suggested that prenatal exposure to maternal stress increases the risk of subsequently developing schizophrenia. METHOD: The five-day invasion and defeat of The Netherlands by the German army in May 1940 constituted a severe, well-circumscribed national stressful event. Individuals exposed and non-exposed to this stressor in the first, second and third trimester of pregnancy were followed up for lifetime schizophrenia outcome through the National Psychiatric Case Register. REGISTER: Cumulative incidence of schizophrenia was higher in the exposed cohort (risk ratio (RR): 1.15, 95% CI 1.03-1.28), especially in those exposed in the first trimester (RR: 1.28, 95% CI 1.07-1.53). Significant interaction with gender was apparent in second trimester exposed cohorts (RR men: 1.35, 95% CI: 1.05-1.74; RR women: 0.83, 95% CI: 0.61-1.12). CONCLUSION: Maternal stress during pregnancy may contribute to the development of vulnerability to schizophrenia. The apparent longer window of exposure in male foetuses may be related to the slower pace of male early cerebral development.

Adult↗
PubMed1998

Special feature: childhood personality characteristics of schizophrenia: manifestations of, or risk factors for, the disorder?

Many retrospective studies, and an increasing number of prospective studies, have identified subtle abnormalities in preschizophrenics from as early as the first year of life. Premorbid characteristics include development delays, cognitive deficits, and abnormal social interactions. Schizoid personality traits have been a particularly well documented finding, and show some specificity in their association with schizophrenia. Information about the premorbid characteristics of schizophrenia has played a major role in the reorientation of the field, from regarding schizophrenia as an adult onset degenerative disorder, to considering it, at least in part, as a neurodevelopmental condition. However, whether the childhood personality traits are a reflection of an underlying brain lesion, or whether they are independent risk factors for the disorder, is uncertain. In the future, the identification of childhood characteristics may enable us to predict those who are at high risk of developing schizophrenia, and may even be useful in formulating preventive policies. However, at present, the powers of prediction are inadequate for such purposes.

Adult↗
PubMed1997

Developmental precursors of affective illness in a general population birth cohort.

BACKGROUND: Recent evidence suggests that neurodevelopmental impairment may be a risk factor for later affective disorder. METHODS: Associations between childhood developmental characteristics and affective disorder were examined in a prospectively studied national British birth cohort of 5362 individuals born between March 3 and March 9, 1946. Mental state examinations by trained interviewers performed at ages 36 and 43 years identified 270 case subjects with adult affective disorder (AD). Teachers' questionnaires completed at age 13 and 15 years identified 195 case subjects who had shown evidence of childhood affective disturbance (CAD). RESULTS: Female gender and low educational test scores at ages 8, 11, and 15 years were a risk factor for AD, CAD, and AD without CAD. In addition, attainment of motor milestones was later in the CAD group (odds ratio [OR] = 1.2; 95% confidence interval [CI], 1.1-1.3), followed by, and independent of, greater risk for speech defects between the ages of 6 and 15 years (OR = 2.0; 95% CI, 1.3-3.0), decreased psychomotor alertness on medical examination between ages 4 and 11 years (OR = 4.6; 95% CI, 2.2-9.7), and an excess of twitching and grimacing motor behaviors in adolescence (OR = 3.9; 95% CI, 2.5-6.1). Persistent CAD was strongly associated with persistent AD (OR = 7.8; 95% CI, 2.6-23.2). CONCLUSION: The findings give credence to the suggestion that affective disorder, especially its early-onset form, is preceded by impaired neurodevelopment.

Adolescent↗
PubMed1997

Persons with intellectual disability receiving psychiatric treatment.

Determinants of (1) referral to psychiatric services and (2) the amount of mental health care consumed were analysed in a population of individuals with intellectual disability, using data from a cumulative mental health case register in a defined geographical area. Associations between level of disability, gender, age and social environment on the one hand, and psychiatric referral and service consumption on the other were expressed as odds ratios (ORs). Being older (OR = 1.9; 95% CI = 1.5-2.5), having milder intellectual disability (OR = 1.4; 95% CI = 0.9-2.3) and living alone (OR = 5.8; 95% CI = 2.8-11.9) predicted a higher probability of receiving psychiatric treatment. Living alone (OR = 15.3; 95% CI = 1.7-136.1) was also associated with higher level of mental health service consumption.

Adolescent↗
PubMed1997

Tardive dyskinesia: who is at risk?

Tardive dyskinesia (TD) has been associated with female gender, affective symptoms and good outcome, but also with negative symptoms, cognitive deterioration and deteriorating illness course. Furthermore, antipsychotic medication is thought to be an important risk factor, yet abnormal movements also occur in patients who have never received such medication. We followed 166 subjects with recent onset of psychotic illness and brief previous exposure to antipsychotic medication. Information on 17 previously reported risk factors was available for 125 patients at baseline and, for factors that vary over time, again at follow-up 4 years later (median, 50 months; interquartile range, 29-70). Movement disorder was assessed at follow-up using the Abnormal Involuntary Movement Scale (AIMS). Six noninteracting variables were independently associated with the 4-year risk of TD: male sex (OR, 2.5; 95% CI, 1.1-5.0), age (OR over quartiles at baseline, 1.6; 95% CI, 1.1-2.2), lack of insight at baseline (OR over four categories, 2.0; 95% CI, 1.2-3.2), time on antipsychotics during the follow-up period (OR over quartiles, 2.3; 95% CI, 1.5-3.4), an increase in negative symptoms during the follow-up period (OR over quartiles, 1.7; 95% CI, 1.2-2.5), and alcohol/drug misuse at follow-up (OR, 3.0; 95% CI, 1.3-7.4). The presence of individual risk factors was found to be of little use as a screening test for subsequent clinically relevant TD. Given the absence of a risk factor, however, the probability that an individual would not develop TD was high. These results suggest that two discrete effects may operate to increase the risk of TD, namely an exogenous factor (medication, drugs), and an illness-related factor, the highest risk being conferred by deteriorating illness course in male patients.

Adult↗
PubMed1996

Explaining sex differences in course and outcome in the functional psychoses.

We addressed the following three questions: (i) are there sex differences in outcome in the functional psychoses?, (ii) what is their effect size, and which variables mediate the effect of sex on outcome?, (iii) is the effect of sex diagnosis-specific? In a prospective study of 166 patients with recent onset psychosis, we established that 4-year outcome was more favourable for women. Female patients more often had a remitting illness course (OR = 3.0; 95% CI: 1.5-5.9), were living independently 14% (4-24%) more of the time, had less evidence of negative symptoms over the follow-up period (OR = 0.3; 0.2-0.7) and were more likely to be employed at follow-up (3.6; 1.8-7.6). The findings did not appear diagnosis-specific, although the sample size was small to test for interaction with diagnostic category. Baseline occupational and social adjustment, clinical expression of illness and age and type of onset explained up to 60% of the sex effect. The processes underlying these factors mediate the effect of sex on outcome.

Adolescent↗