Repository logo
 

Transdiagnostic dimensions of psychopathology at first episode psychosis: findings from the multinational EU-GEI study.

Published version
Peer-reviewed

Type

Article

Change log

Authors

Di Forti, Marta 
Gayer-Anderson, Charlotte 
Ferraro, Laura 
Jongsma, Hannah E 

Abstract

BACKGROUND: The value of the nosological distinction between non-affective and affective psychosis has frequently been challenged. We aimed to investigate the transdiagnostic dimensional structure and associated characteristics of psychopathology at First Episode Psychosis (FEP). Regardless of diagnostic categories, we expected that positive symptoms occurred more frequently in ethnic minority groups and in more densely populated environments, and that negative symptoms were associated with indices of neurodevelopmental impairment. METHOD: This study included 2182 FEP individuals recruited across six countries, as part of the EUropean network of national schizophrenia networks studying Gene-Environment Interactions (EU-GEI) study. Symptom ratings were analysed using multidimensional item response modelling in Mplus to estimate five theory-based models of psychosis. We used multiple regression models to examine demographic and context factors associated with symptom dimensions. RESULTS: A bifactor model, composed of one general factor and five specific dimensions of positive, negative, disorganization, manic and depressive symptoms, best-represented associations among ratings of psychotic symptoms. Positive symptoms were more common in ethnic minority groups. Urbanicity was associated with a higher score on the general factor. Men presented with more negative and less depressive symptoms than women. Early age-at-first-contact with psychiatric services was associated with higher scores on negative, disorganized, and manic symptom dimensions. CONCLUSIONS: Our results suggest that the bifactor model of psychopathology holds across diagnostic categories of non-affective and affective psychosis at FEP, and demographic and context determinants map onto general and specific symptom dimensions. These findings have implications for tailoring symptom-specific treatments and inform research into the mood-psychosis spectrum.

Description

Keywords

Bifactor model, diagnostic categories, first episode psychosis, psychopathology, symptom dimensions, Adult, Affective Disorders, Psychotic, Bipolar Disorder, Depression, Europe, Female, Humans, Male, Models, Psychological, Psychiatric Status Rating Scales, Psychopathology, Psychotic Disorders, ROC Curve, Schizophrenia, Schizophrenic Psychology, Young Adult

Journal Title

Psychol Med

Conference Name

Journal ISSN

0033-2917
1469-8978

Volume Title

49

Publisher

Cambridge University Press (CUP)