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

Diego Quattrone*, Marta Di Forti, Charlotte Gayer-Anderson, Laura Ferraro, Hannah E. Jongsma, Giada Tripoli, Caterina La Cascia, Daniele La Barbera, Ilaria Tarricone, Domenico Berardi, Andrei Szoke, Celso Arango, Antonio Lasalvia, Andrea Tortelli, Pierre-Michel Llorca, Lieuwe de Haan, Eva Velthorst, Julio Bobes, Miguel Bernardo, Julio SanjuanJose Luis Santos, Manuel Arrojo, Cristina Marta Del-Ben, Paulo Rossi Menezes, Jean-Paul Selten, Peter B. Jones, James B. Kirkbride, Alexander L. Richards, Michael C. O'Donovan, Pak C. Sham, Evangelos Vassos, Bart P. F. Rutten, Jim van Os, Craig Morgan, Cathryn M. Lewis, Robin M. Murray, Ulrich Reininghaus, Kathryn Hubbard, Stephanie Beards, Simona A. Stilo, Mara Parellada, Pedro Cuadrado, Jose Juan Rodriguez Solano, Angel Carracedo, Enrique Garcia Bernardo, Laura Roldan, Gonzalo Lopez, Bibiana Cabrera, Esther Lorente-Rovira, Paz Garcia-Portilla, EU-GEI WP2 Group

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

50 Citations (Web of Science)

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.

Original languageEnglish
Pages (from-to)1378-1391
Number of pages14
JournalPsychological Medicine
Volume49
Issue number8
DOIs
Publication statusPublished - Jun 2019

Keywords

  • Bifactor model
  • diagnostic categories
  • first episode psychosis
  • psychopathology
  • symptom dimensions
  • NEGATIVE SYNDROME SCALE
  • BIPOLAR DISORDER
  • SYMPTOM DIMENSIONS
  • BIFACTOR MODEL
  • GENETIC-RELATIONSHIPS
  • GENDER-DIFFERENCES
  • SEX-DIFFERENCES
  • 5-FACTOR MODEL
  • WORKING GROUP
  • DSM-V

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