The social disabilities described in autism are often reminiscent of classic descriptions of social disinterest and emotional coldness of schizoid personality types. Clinicians often report encountering brief psychotic episodes in people with autism spectrum disorders (ASDs) additionally many adults with ASD have had a 'misdiagnosis' of schizophrenia, particularly before the 1980s when autism was introduced in classification systems. Both disorders are defined by deficits in interpersonal relationships, and social skills1;2 frequently displayed as active and passive social withdrawal. Also it has been suggested that both disorders may be considered as existing on a continuum ranging from mild symptoms to clinical disorder3;4. Mild symptoms of both disorders are prevalent in community samples3;5 Theoretically it has been suggested by Crespi & Badcock6 that autism and psychosis are diametrically opposite disorders of the social brain, (the areas of the brain that are associated with social information processing). They suggest that austim is characterised by hypo-development of of social cognitive skills and that psychosis is characterised by hyper-development of these skills. There is reliable evidence for social cognitive deficits in both disorders7;8. There have been a few previous studies on social cognition9-11 12which have compared small clinical samples of both groups. These studies have been cross-sectional and some have included healthy comparison groups. The findings of these studies have been mixed with some studies suggesting similar deficits and others finding differences. There have been no previous studies using longitudinal or cohort data.

If there is a true overlap between autistic spectrum and psychosis spectrum disorders one would expect to find an association between autistm spectrum traits and psychotic symptoms. This study aims to investigate these links in the ALSPAC birth cohort using previously identified autistic spectrum traits, a diagnosis of autism taken from medical records, and later experience of psychotic symptoms.

Method

Sample

ALSPAC birth cohort

Study sample

Cohort members who have contributed to the data used to identify autistic spectrum traits and who have participated in the clinical interview to detect psychotic symptoms.

Measures

Primary Outcome

PLIKSi. Information on experience of 12 core psychotic symptoms was collected from cohort members who attended an ALSPAC clinic at the age of approximately 12 years. For the purposes of this study the variable is dichotomously coded as; experience of suspected or definite symptoms over the previous 6 months (yes), and no experience of symptoms over the previous 6 months (no).

Exposure

Four of the seven autistic spectrum traits identifed by Steer & Golding13; verbal ability, language acquisition, social understanding, semantic-pragmatic skills.

A confirmed diagnosis of autism taken from medical records

Other Measures

Demographic measures from the ALSPAC database

Statistical Analysis

Multivariate logistic regression models will be used to examine the association between autistic spectrum traits and later experience of psychotic symptoms

Implications

This analysis will confirm or otherwise any overlap between autism and psychosis in a large community sample. It will generate new information on whether people with autism may be more likely to develop a later psychotic illness, and if so, which autistic traits may be most strongly associated.

Reference List

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