Schizotypal components in people at high risk of developing schizophrenia: early findings from the Edinburgh High-Risk Study.
BACKGROUND
The study of high-risk groups and the development of schizophrenia.


OBJECTIVE
To investigate further schizotypy, measured by the Structured Interview for Schizotypy (SIS), and to examine relationships between schizotypal components, psychotic symptoms on the Present State Examination (PSE) and subsequent schizophrenia.


METHODS
The SIS and PSE were administered on entry. Schizophrenia onsets were recorded during follow-up.


RESULTS
The SIS yielded four principal components labelled social withdrawal, psychotic symptoms, socio-emotional dysfunction and odd behaviour. On entry, these differentiated between controls, subjects at risk for schizophrenia with and without symptoms and patients with schizophrenia. Seven of 78 subjects at risk developed schizophrenia within 39 months. This was best predicted by combining the four SIS components.


CONCLUSIONS
Schizotypy is heterogeneous and may become psychosis, particularly if several of its components are present. As psychosis develops, odd behaviour gives way to psychotic symptoms and social function deteriorates.
Miller
Patrick
P
Department of Psychiatry, University of Edinburgh, UK. Pmmill@srvl.med.ed.ac.uk
Byrne
Majella
M
Hodges
Ann
A
Lawrie
Stephen M
SM
Owens
David G C
DG
Johnstone
Eve C
EC
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007406:Interview, Psychological; D008297:Male; D011237:Predictive Value of Tests; D011379:Prognosis; D011569:Psychiatric Status Rating Scales; D012307:Risk Factors; D012559:Schizophrenia / Q000209:etiology*; D012569:Schizotypal Personality Disorder / Q000175:diagnosis / Q000523:psychology*; D012680:Sensitivity and Specificity