Wigman, J.T.W.

Early trauma and familial risk in the development of the extended psychosis phenotype in adolescence (Article)

2012-10-01T00:00:00Z

Objective: Both genetic and environmental factors are thought to play a role in the development of psychotic outcomes; however, their respective contributions over time, including possible developmental interactions, remain largely unknown. Method: The contribution of parental general and psychotic psychopathology as proxies of genetic risk to the development of subthreshold psychosis and its hypothesized interaction with childhood trauma were studied in a general population sample of 2230 adolescents, followed from age 10-16years. Outcome measures were: i) level of psychotic experiences at age 16years and ii) persistence of such experiences over the total follow-up period. Results: General parental psychopathology was associated with CAPE score (OR=1.08; P<0.043 for highest quintile) and suggestively predicted psychosis persistence (OR, 1.16; P<0.072). Psychotic parental psychopathology was suggestively associated with CAPE score (OR, 2.25; P<0.063 for highest quintile), predicted membership of the Persistent group (OR, 3.72; P<0.039) and suggestively predicted membership of the Decreasing group (OR 2.04; P<0.051). Childhood trauma was associated with CAPE score and with all developmental trajectories of subclinical psychosis. No evidence was found for an interaction between trauma and parental psychopathology. Conclusion: The development and persistence of subthreshold psychotic symptoms may be conditional on non-interacting proxy genetic and environmental influences.

The structure of the extended psychosis phenotype in early adolescence - A cross-sample replication (Article)

2011-07-01T00:00:00Z

The extended psychosis phenotype, or the expression of nonclinical positive psychotic experiences, is already prevalent in adolescence and has a dose-response risk relationship with later psychotic disorder. In 2 large adolescent general population samples (n = 5422 and n = 2230), prevalence and structure of the extended psychosis phenotype was investigated. Positive psychotic experiences, broadly defined, were reported by the majority of adolescents. Exploratory analysis with Structural Equation Modelling (Exploratory Factor Analysis followed by Confirmatory Factor Analysis [CFA]) in sample 1 suggested that psychotic experiences were best represented by 5 underlying dimensions; CFA in sample 2 provided a replication of this model. Dimensions were labeled Hallucinations, Delusions, Paranoia, Grandiosity, and Paranormal beliefs. Prevalences differed strongly, Hallucinations having the lowest and Paranoia having the highest rates. Girls reported more experiences on all dimensions, except Grandiosity, and from age 12 to 16 years rates increased. Hallucinations, Delusions, and Paranoia, but not Grandiosity and Paranormal beliefs, were associated with distress and general measures of psychopathology. Thus, only some of the dimensions of the extended psychosis phenotype in young people may represent a continuum with more severe psychopathology and predict later psychiatric disorder.

Evidence for a persistent, environment-dependent and deteriorating subtype of subclinical psychotic experiences: a 6-year longitudinal general population study (Article)

2011-04-11T00:00:00Z

BACKGROUND: Research suggests that subclinical psychotic experiences during adolescence represent the behavioral expression of liability for psychosis. Little is known, however, about the longitudinal trajectory of liability in general population samples. METHOD: Growth mixture modeling was used to examine longitudinal trajectories of self-reported positive psychotic experiences in the Youth Self Report (YSR), completed three times over a period of 6 years by a general population cohort of adolescents aged 10-11 years at baseline (n=2230). RESULTS: Four groups with distinct developmental trajectories of low, decreasing, increasing and persistent levels of mild positive psychotic experiences were revealed. The persistent trajectory was associated strongly with cannabis use, childhood trauma, developmental problems and ethnic minority status, and consistently displayed strong associations with factors known to predict transition from subclinical psychotic experience to clinical psychotic disorder (severity of and secondary distress due to psychotic experiences, social and attentional problems and affective dysregulation) and also with high levels of parental-reported psychotic experiences and use of mental health care at the end of the follow-up period. Progressively weaker associations were found for the increasing, decreasing and low trajectories respectively. CONCLUSIONS: The results suggest that the outcome of early developmental deviation associated with later expression of psychotic experiences is contingent on the degree of later interaction with environmental risks inducing, first, persistence of psychotic experiences and, second, progression to onset of need for care and service use. Insight into the longitudinal dynamics of risk states in representative samples may contribute to the development of targeted early intervention in psychosis.