The antecedents of schizophrenia: a review of birth cohort studies.

Queensland Centre for Mental Health Research, The Park Centre for Mental Health, Wacol, QLD 4076, Australia.
Schizophrenia Bulletin (Impact Factor: 8.61). 05/2009; 35(3):603-23. DOI: 10.1093/schbul/sbn084
Source: PubMed Central

ABSTRACT Birth cohort (BC) studies demonstrate that individuals who develop schizophrenia differ from the general population on a range of developmental indices. The aims of this article were to summarize key findings from BC studies in order to identify areas of convergence and to outline areas requiring further research.
We define BC studies as studies based on general population BCs where data are collected prospectively from birth or childhood and which identify schizophrenia or related disorders as an outcome. To identify such studies, we searched various electronic databases using the search parameters (schizo* OR psych*) AND (birth cohort). We also checked the references of relevant articles and previous reviews.
We identified 11 BCs from 7 countries that have examined schizophrenia as an outcome in adulthood. There is relatively consistent evidence that, as a group, children who later develop schizophrenia have behavioral disturbances and psychopathology, intellectual and language deficits, and early motor delays. Evidence with respect to alterations in language, educational performance, and physical growth has also been identified in some studies. BC studies have also contributed evidence about a wide range of putative risk factors for schizophrenia.
BC studies have provided important, convergent insights into how the developmental trajectory of individuals who develop schizophrenia differs from their peers. The combination of new paradigms and larger cohorts, with the tools of modern epidemiology and biomedical science, is advancing our understanding of the developmental pathways to schizophrenia.

Download full-text


Available from: Peter Jones, Sep 02, 2014
1 Follower
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Although epidemiological studies provide strong support for demographic and environmental risk factors in psychotic disorders, few data examine how these risk factors relate to the putative aberrant neurodevelopment associated with illness. The present study examined how the accumulation of risk factors including low IQ, low parental socioeconomic status, history of adolescent cannabis use and childhood trauma, and high levels of subclinical psychotic-like experiences contributed to aberrant neurodevelopmental outcomes in 112 otherwise healthy adults recruited from the community. Participants were studied with diffusion tensor imaging, and voxel-wise statistical analysis of fractional anisotropy (FA) using tract-based spatial statistics was used to examine the relation between cumulative risk (CR) for psychosis and white matter (WM) integrity across the whole brain. Analyses revealed that higher CR was significantly associated with lower FA in a cluster in the left superior longitudinal fasciculus. These results suggest that risk factors previously associated with psychotic disorders are associated with WM integrity even in otherwise healthy adults and may provide insight into how previously identified risk factors contribute to the structural brain abnormalities associated with psychotic illness. Prospective longitudinal studies examining the effect of risk factors on the developmental trajectory of brain WM are warranted.
    Psychiatry Research Neuroimaging 12/2014; DOI:10.1016/j.pscychresns.2014.09.001 · 2.83 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: An argument often used to support the view that psychotic experiences (PEs) in general population samples are a valid phenotype for studying the aetiology of schizophrenia is that risk factors for schizophrenia show similar patterns of association with PEs. However, PEs often co-occur with depression, and no study has explicitly tested whether risk factors for schizophrenia are shared between PEs and depression, or are psychopathology specific, while jointly modelling both outcomes.
    Psychological Medicine 09/2014; 44(12):2557-2566. DOI:10.1017/S0033291714000026 · 5.43 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Etiologies of psychotic disorders (schizophrenia and bipolar disorder) are conceptualized as interplay between genetic- and environmental factors. The adolescent period is characterized by changes in social roles and expectations that may interact with biological changes or psychosocial stressors. Few studies focus on the adolescents’ own reports of perceived risk factors. To assess differences at age 16 between persons who later develop psychotic disorders (“Confirmed Psychosis”, CP) and their class-mates (“Population Controls”, PC) we collected information on: 1) Social support factors (size of social network and expectancies of social support from friends), 2) Cognitive functioning (concentrating in the classroom, actual grades and expectancies of own academic achievements) and 3) Problems and stressors in families (illness or loss of work for parents), and in relationship with others (exposure to bullying, violence or sexual violation). Self-reported data from students at 15–16 years of age were linked to the case-registers from the “Thematically Organized Psychosis (TOP) Study”. The CP group reported more economic problems in their families, smaller social network and lower academic expectation than the PC group. The results support the notion that long-term socioeconomic stressors in adolescence may serve as risk factors for the development of psychotic disorders.
    03/2014; 215(3). DOI:10.1016/j.psychres.2013.12.048