Winfried Laan

Incidence of schizophrenia among ethnic minorities in the Netherlands : A four-year first-contact study

There is only one previous report on the first-contact incidence of schizophrenia among immigrants in the Netherlands, which was based on a small number of cases, particularly for second generation immigrants. We conducted another two-year first-contact incidence study in the same geographical area, combined the data of both studies and compared risks over all four years. The incidence of schizophrenia was increased for all first generation non-Western immigrants. The risk was particularly high for second generation immigrants: the age- and gender-adjusted incidence rate ratio was 5.8 (95% CI, 2.9-11.4) for Moroccans, 2.9 (1.6-5.0) for Surinamese, 2.3 (1.0-5.4) for Turks, and 3.5 (1.8-6.8) for immigrants from other non-Western countries.

Early course of schizophrenia in a representative Dutch incidence cohort

PURPOSE To describe the early course of psychotic disorders in general and to examine whether certain variables can predict the early course of schizophrenic disorders (DSM-IV: schizophrenia, schizophreniform or schizoaffective disorder). SUBJECTS AND METHOD Follow-up and re-diagnosis of a highly representative Dutch incidence cohort (N=181), thirty months after first contact with a physician for a psychotic disorder. Poor course was defined as a continuous psychotic illness or a score of less than 39 on the Global Assessment of Functioning scale. RESULTS The follow-up rate was 92%. 125 Subjects were diagnosed with a schizophrenic disorder. Poor course was present in 70 of these subjects (56%). Univariable analysis showed that male sex, heavy cannabis use during the follow-up period (sometimes or often more than one joint a day) and long duration of dysfunctioning before psychosis onset (>1 month) were predictors of poor course, while age at onset, ethnicity, socioeconomic status and duration of untreated psychosis (trend, p=0.08) were not. The effect of cannabis was confounded by sex. Multivariable analysis showed that male sex was the sole significant and independent predictor of poor course and explained 13% of the variation. The odds ratio for males, adjusted for duration of pre-psychotic dysfunctioning and cannabis use during the follow-up period, was 3.0 (95% CI, 1.0-8.9). STRENGTHS AND LIMITATIONS: This is the first study to examine the influence of cannabis in an epidemiological, highly representative sample. A limitation was the sample size. CONCLUSION Male sex is an independent risk factor for an unfavorable early course in schizophrenia.

Non-steroidal anti-inflammatory drugs and the risk of psychosis

The objective of the current research was to examine the relation between non-steroidal anti-inflammatory drugs (NSAID) use and risk of psychosis. To this end we performed a longitudinal case-control study using prescription data from a Dutch health insurance company. Men aged 25 years or over and women aged 30 years or over were excluded to prevent inclusion of non-incident cases. This resulted in eighty-two cases and 359 randomly selected controls from the same population. The overall relative risk of incident antipsychotic use for NSAID users, adjusted for age and prescription frequency, was 0.80 (95% CI: 0.48-1.33). After stratification for gender the risk of psychosis was significantly lower (59%) in male NSAID users only. The relative risks for male and female subjects were 0.41 (95% CI: 0.17-0.97) and 1.31 (95% CI: 0.65-2.64), respectively. These results suggest that in men NSAIDs may lower the risk of psychosis.

Psychosocial functioning in first-episode psychosis and associations with neurocognition, social cognition, psychotic and affective symptoms

Most studies on the determinants of psychosocial functioning in first‐episode psychosis used few predictors. This study examines the effects of multiple cognitive domains and multiple symptoms on psychosocial functioning.

Cognitive deficits and ethnicity: a cohort study of early psychosis patients in The Netherlands

PurposeIncidence rates of psychotic disorders are higher in immigrant groups compared to native populations. This increased risk may partly be explained by misdiagnosis. Neurocognitive deficits are a core feature of psychotic disorders, but little is known about the relationship between migration and cognition in psychotic disorders. We examined whether immigrant patients have cognitive deficits similar to non-immigrant patients, in order to investigate the plausibility of misdiagnosis as explanation for increased incidence rates.MethodsPatients who made first contact for non-affective psychotic disorder were assessed in the cognitive domains sustained attention, immediate recall and delayed recall. Immigrant patients were compared to Dutch patients on cognitive performance.Results407 Patients diagnosed with a non-affective psychotic disorder completed cognitive assessment (157 Dutch, 250 immigrants). Both Dutch and immigrant patients showed large cognitive deficits. Between-subgroup comparisons revealed large cognitive deficits for immigrants compared to Dutch, especially for immigrants from Morocco, Turkey and other non-Western countries.ConclusionsThese results indicate that immigrant status is associated with poorer cognitive functioning in early psychosis. The findings argue against diagnostic bias as an explanation for the increased incidence of psychotic disorders in immigrants.

Psychopathology, cognition and outcome in Dutch and immigrant first-episode psychosis patients

The primary aim was to examine differences in baseline symptom expression, neurocognition, social cognition and psychosocial functioning between Dutch, first‐generation immigrants and second‐generation immigrants with a first‐episode psychosis (FEP). The secondary aim was to examine functional and symptomatic change and between‐group differences at 12‐months follow‐up. Associations between migration, baseline characteristics and outcome were explored.

Poster #240 DIFFERENTIAL ASSOCIATIONS BETWEEN COGNITION AND OUTCOME IN EARLY PSYCHOSIS: A COHORT STUDY OF EARLY PSYCHOSIS PATIENTS IN THE NETHERLANDS

Background: Substantial research done in the last few decades indicates that various neurocognition (NC) and social cognition (SC) domains are strongly associated with functional outcome in psychotic disorders. However, many studies investigating these associations have not used fully comprehensive cognitive batteries and/or a limited variety in outcome measures. Differences in demographic characteristics and methodology make integration of these findings problematic. Subsequently, our understanding of the differential associations between cognition and functional outcome remains limited, especially concerning the early stages of these disorders. This comprehensive cross-sectional study aims to investigate differential associations between cognition and outcome in a naturalistic cohort of early psychosis patients. Methods: The cognitive test-battery comprised fifteen neuropsychological measures to assess (a) general cognition, (b) seven NC domains (Attention, Problem solving, Speed of processing, Verbal fluency, Verbal learning, Visual learning and Working memory) and (c) four SC domains (Facial affect perception, Theory of Mind, Social knowledge and Social cognitive biases). The following global and specific outcome domains were assessed: (1) global functioning (GAF), (2) global clinical impression (CGI), (3) global social functioning (GSF) (4) social useful activities, including study and work (SUA) (5) personal and social relationships (PSR), (6) self-care (SeC), (7) disturbing and/or aggressive behaviour (DAB), (8) perceived chronic stress (PCS), and (9) health perception (HP). Participants included 114 patients with a first-episode psychotic disorder, of which 105 completed neuropsychological assessment (92,1%; 74 males and 31 females). Bivariate correlations between cognitive domains and functional outcome variables will be examined. Results: Of the twelve cognitive domains, three were related to global outcome: Attention to CGI (r=0.33), Speed of processing to GAF/CGI/GSF (rmean=0.27), and Facial affect perception to GAF/CGI/GSF (rmean=0.33). Seven cognitive domains were related to specific outcome domains: Attention to SUA/HP (rmean=0.26), Verbal fluency to SeC (r=0.22), Verbal learning to SUA/HP (rmean=0.25), Visual learning to HP (r=0.29), Working memory to SUA (r=0.23), Facial affect perception to SUA/PSR/DAB/HP (rmean =0.29), and Social cognitive biases to PSR/DAB/PCS/HP (rmean=0.42). Of the twelve cognitive domains, only Attention and Facial affect perception were related to both global and specific functional outcome domains. The cognitive domains Problem solving, General cognition, Theory of mind and Social knowledge were unrelated to all functional outcome domains. Discussion: Findings suggest that both NC and SC are substantially but selectively associated with various functional outcome domains. The heterogeneous cognition-outcome relationship pattern in our data illustrates that specificity is crucial in order to identify viable cognitive treatment targets in early psychosis patients. Implications for early psychosis interventions and future research are discussed.