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W F Scholte

Publications and source records attributed to W F Scholte.

11 recordsLinked to original sources
PubMed2006

[Clozapine-induced agranulocytosis: genetic risk factors and an immunologic explanatory model].

BACKGROUND: Clozapine, an atypical antipsychotic used in the treatment of refractory schizophrenia, causes agranulocytosis in 0.8% of patients. The risk factors for clozapine-induced agranulocytosis (CIA) and the underlying mechanisms are unclear. AIM: To ascertain the genetic and immunological risk factors for CIA, and on the basis of these findings to construct an explanatory model for CIA. METHOD: We reviewed the literature via Medline (from 1966 to May 2004) and EMBASE (from 1980 to May 2004) using the search terms 'clozapine' and 'agranulocytosis'. RESULTS: We found 8 case-control studies that fulfilled our selection criteria. In schizophrenia patients, CIA appeared to be significantly associated with certain haplotypes of HLA (human leukocyte antigens) genes, with the 4b,3d microsatellite alleles of TNF (tumor necrosis factor), with variant genes of HSP 70 (heat-shock protein), and with NQO2 (dihydronicotinamide riboside quinone oxidoreductase) gene polymorphism. Most of these genetic findings are interrelated. Gene abnormalities of this kind probably play an important aetiological role in CIA and may provide a basis for the construction of an immuno-toxic explanatory model for CIA. CONCLUSION: It seems likely that CIA can be explained on the basis of genetic and immunotoxic factors. The model should help us to understand how agranulocytosis can be caused by various antipsychotics and how it can be treated. However, it is not yet possible to identify patients who are particularly at risk for CIA.

Agranulocytosis↗
PubMed2001

[Mania during the use of a combination preparation with St. John's wort (Hypericum perforatum)].

A 23-year-old woman with no psychiatric history developed acute mania and psychosis while using St. John's wort at a high dosage (Valdispert 'balans', a combination of valerian extract and hypericin). She was diagnosed as having substance-induced mood disorder, with manic features (DSM-IV). Discontinuation of the use of the product and treatment with olanzapine led to complete recovery. No causal relationship between the use of the extract and the mania was established, but the course of the mania does suggest this association. St. John's wort is a popular herbal antidepressant. Hyperforin and hypericin, components of St. John's wort, inhibit synaptosomal serotonin, noradrenaline and dopamine uptake. The mechanism of action of St. John's wort is, however, not yet fully understood. St. John's wort should therefore be used with caution, especially in patients with a bipolar disorder.

Adult↗
PubMed2000

The prevalence of mental health problems in Rwandan and Burundese refugee camps.

OBJECTIVE: We examined the prevalence of mental health problems in refugees living in camps that emerged in Tanzania during the Rwanda crisis that started in 1994. METHOD: Using the 28-item version of the General Health Questionnaire (GHQ-28), we examined two samples: a random sample (n = 854) and a sample of clients of a psychosocial support programme in these camps (n = 23). Sensitivity, specificity and positive- and negative predictive values were estimated for several cut-off scores of the GHQ-28. RESULTS: The prevalence of serious mental health problems was estimated at 50% (SE 12%). When using the GHQ-28 as a screener, a cut-off score of 14 is recommended. CONCLUSION: Given the high prevalence of mental health problems, psychosocial programmes for large refugee populations should aim at strengthening community structures and supporting groups instead of focusing at individuals. The screening capacity of the GHQ-28 could be used to identify mentally vulnerable groups.

Adolescent↗
PubMed1998

Early detection and intervention in schizophrenia.

During the course of schizophrenia, symptoms tend to increase at the highest rate during the first 5 years of the disease. Moreover, 10% of suicides by schizophrenic patients occur within the first 10 years of schizophrenia being diagnosed. These facts emphasize the importance of early intervention to improve the course of the disease before further deterioration. The use of psychosocial interventions and drug management programmes, in addition to maintenance antipsychotic medication, reduces the risk of psychotic relapse. Continuity of care from inpatient to outpatient treatment also significantly improves outcome, largely as a result of better drug compliance. It appears, however, that the addition of a behavioural family intervention alone to a standard programme offers little additional benefit. The benefits of intervention programmes last only as long as the programme, and patients should continue with such intensive treatment strategies for at least the duration of the critical phase. Under these circumstances, very mild psychotic complaints may be recognized at an early stage so that treatment can begin even earlier, further increasing the chance of an optimal long-term outcome. Further studies of early intervention and relapse prevention are required to support these findings.

Antipsychotic Agents↗
PubMed1997

Patient attributes and expressed emotion as risk factors for psychotic relapse.

In the context of a prospective, controlled treatment study, contrasting family interventions with individual treatment, the role of expressed emotion (EE) as a predictor of relapse was examined in patients with recent-onset schizophrenia and related disorders (n = 97). EE was compared with 13 predictor variables. The variables, taken from EE and family intervention studies, related to demography, premorbid functioning, present and past illness history, and comorbid substance abuse. Psychotic relapse was operationalized with a conservatively measured relapse criterion, composed of monthly ratings based on the Brief Psychiatric Rating Scale and on clinical judgment during the 12 months of outpatient treatment. Of the 14 predictor variables entered in stepwise survival analyses, 6 variables had probable predictive power on the conservative relapse criterion. These variables were entered in a Cox regression model. EE turned out to be the major predictor of relapse in the overall sample (hazard ratio [HR] 4.90; confidence interval [CI] 1.05-22.92). This finding remained when only patients with a first psychotic episode (p = 0.02) and patients in the individual treatment condition (p = 0.001) were examined. Cannabis abuse was the major predictor of relapse in patients with high-EE families (HR 4.27; CI 1.12-16.29).

Adolescent↗
PubMed1996

Symptoms, cognitive and social functioning in recent-onset schizophrenia: a longitudinal study.

The relationships among symptoms, cognitive functioning and social functioning were investigated in patients with schizophrenia over a period of 15 months. Patients with a mood disorder, a normal control group and a sample of parents of the schizophrenic patients also completed the cognitive tests. In the schizophrenia sample, only disorganisation was correlated with cognitive performance, which was interpreted as further evidence that disorganisation is a separate symptom dimension of schizophrenia. Against expectations, with two of three measurements no significant correlations were found between negative symptoms and cognitive performance. With these two measurements, however, a curvilinear association between negative symptoms and cognitive performance was observed, suggesting that negative symptoms are not a unitary concept. Finally, tentative evidence could be obtained for speed of information processing and selective attention as markers for vulnerability, although the latter is not specific for schizophrenia.

Adult↗
PubMed1995

Dimensions and subtypes of recent-onset schizophrenia. A longitudinal analysis.

A sample of young patients with schizophrenia was studied in a longitudinal design to investigate the stability of an earlier reported four-dimensional symptom model (positive symptoms, negative symptoms, disorganization, and depression). Symptoms were measured in an acute phase soon after hospitalization, in a remitted stage 3 months later, and in a "mixed" phase 1 year after the second assessment. A different factor structure was found at each measurement, but a stable four-dimensional structure could be defined that closely resembled the factor structure of the first assessment. The symptom dimensions were uncorrelated, except disorganization and depression. Whether meaningful subtypes could be defined using statistical criteria also was investigated. With cluster analysis, four subtypes were defined that could be characterized as follows: rapid treatment responders, slower responders, and two relapse groups. Although some indication of the validity of these subtypes was found, it is concluded that there is a high risk of creating artificial boundaries with this approach.

Adolescent↗
PubMed1994

Relapse criteria in schizophrenic disorders: different perspectives.

Relapse and exacerbation of psychotic symptoms were investigated in a prospective study of 88 patients with recent-onset schizophrenia and related disorders. Relapse definitions were derived from expressed emotion and family intervention studies and based on the Brief Psychiatric Rating Scale (BPRS), the Present State Examination, and clinical judgment. Results indicate that research and clinical criteria represent different perspectives on relapse. Clinical criteria provide a validity check that can verify BPRS-rated changes in partially remitted patients.

Adolescent↗
PubMed1993

Symptom dimensions and cognitive and social functioning in recent-onset schizophrenia.

The relationships among symptoms, cognitive functioning and social functioning were investigated in 60 patients with recent-onset schizophrenia. Positive symptoms were unrelated to cognitive measures. Disorganization and depressive symptoms were correlated significantly with Card Sorting performance. Furthermore, only negative symptoms were correlated significantly with social functioning. These results replicate earlier studies with chronic and mixed samples, and support the validity of disorganization as a separate symptom dimension. In contrast to most previous studies, no significant correlations were found between negative symptoms and cognitive measures. However, some evidence was found for a non-linear association between negative symptoms had several cognitive measures. The variation explained by a curvilinear model was not high, but for some cognitive measures this model was clearly superior to a linear model. If replicated, this finding supports the position that cross-sectionally measured negative symptoms cannot be viewed as a unitary concept.

Adolescent↗
PubMed1993

A dimensional and categorical approach to the symptomatology of recent-onset schizophrenia.

Sixty-five patients with recent-onset schizophrenia were assessed with two widely used symptom scales, the Brief Psychiatric Rating Scale-Expanded (BPRS-E) and the Psychiatric Assessment Scale (Manchester scale). Principal components analysis of the BPRS-E scores yielded a four-dimensional structure: positive symptoms, negative symptoms, disorganization, and depression. With the Psychiatric Assessment Scale, three dimensions were found: the positive symptoms (delusions, hallucinations) and disorganization (incoherence) appeared in one dimension. A categorical analysis resulted in predominantly positive, negative, and disorganized clusters, but more than half of the sample could not be allocated to any of these groups.

Adolescent↗