TY - JOUR
T1 - Variation of subclinical psychosis across 16 sites in Europe and Brazil
T2 - findings from the multi-national EU-GEI study
AU - D'Andrea, Giuseppe
AU - Quattrone, Diego
AU - Malone, Kathryn
AU - Tripoli, Giada
AU - Trotta, Giulia
AU - Spinazzola, Edoardo
AU - Gayer-Anderson, Charlotte
AU - Jongsma, Hannah E
AU - Sideli, Lucia
AU - Stilo, Simona A
AU - La Cascia, Caterina
AU - Ferraro, Laura
AU - Lasalvia, Antonio
AU - Tosato, Sarah
AU - Tortelli, Andrea
AU - Velthorst, Eva
AU - de Haan, Lieuwe
AU - Llorca, Pierre-Michel
AU - Rossi Menezes, Paulo
AU - Santos, Jose Luis
AU - Arrojo, Manuel
AU - Bobes, Julio
AU - Sanjuán, Julio
AU - Bernardo, Miguel
AU - Arango, Celso
AU - Kirkbride, James B
AU - Jones, Peter B
AU - Rutten, Bart P
AU - Van Os, Jim
AU - Selten, Jean-Paul
AU - Vassos, Evangelos
AU - Schürhoff, Franck
AU - Szöke, Andrei
AU - Pignon, Baptiste
AU - O'Donovan, Michael
AU - Richards, Alexander
AU - Morgan, Craig
AU - Di Forti, Marta
AU - Tarricone, Ilaria
AU - Murray, Robin M
PY - 2024/6
Y1 - 2024/6
N2 - BACKGROUND: Incidence of first-episode psychosis (FEP) varies substantially across geographic regions. Phenotypes of subclinical psychosis (SP), such as psychotic-like experiences (PLEs) and schizotypy, present several similarities with psychosis. We aimed to examine whether SP measures varied across different sites and whether this variation was comparable with FEP incidence within the same areas. We further examined contribution of environmental and genetic factors to SP. METHODS: We used data from 1497 controls recruited in 16 different sites across 6 countries. Factor scores for several psychopathological dimensions of schizotypy and PLEs were obtained using multidimensional item response theory models. Variation of these scores was assessed using multi-level regression analysis to estimate individual and between-sites variance adjusting for age, sex, education, migrant, employment and relational status, childhood adversity, and cannabis use. In the final model we added local FEP incidence as a second-level variable. Association with genetic liability was examined separately. RESULTS: Schizotypy showed a large between-sites variation with up to 15% of variance attributable to site-level characteristics. Adding local FEP incidence to the model considerably reduced the between-sites unexplained schizotypy variance. PLEs did not show as much variation. Overall, SP was associated with younger age, migrant, unmarried, unemployed and less educated individuals, cannabis use, and childhood adversity. Both phenotypes were associated with genetic liability to schizophrenia. CONCLUSIONS: Schizotypy showed substantial between-sites variation, being more represented in areas where FEP incidence is higher. This supports the hypothesis that shared contextual factors shape the between-sites variation of psychosis across the spectrum.
AB - BACKGROUND: Incidence of first-episode psychosis (FEP) varies substantially across geographic regions. Phenotypes of subclinical psychosis (SP), such as psychotic-like experiences (PLEs) and schizotypy, present several similarities with psychosis. We aimed to examine whether SP measures varied across different sites and whether this variation was comparable with FEP incidence within the same areas. We further examined contribution of environmental and genetic factors to SP. METHODS: We used data from 1497 controls recruited in 16 different sites across 6 countries. Factor scores for several psychopathological dimensions of schizotypy and PLEs were obtained using multidimensional item response theory models. Variation of these scores was assessed using multi-level regression analysis to estimate individual and between-sites variance adjusting for age, sex, education, migrant, employment and relational status, childhood adversity, and cannabis use. In the final model we added local FEP incidence as a second-level variable. Association with genetic liability was examined separately. RESULTS: Schizotypy showed a large between-sites variation with up to 15% of variance attributable to site-level characteristics. Adding local FEP incidence to the model considerably reduced the between-sites unexplained schizotypy variance. PLEs did not show as much variation. Overall, SP was associated with younger age, migrant, unmarried, unemployed and less educated individuals, cannabis use, and childhood adversity. Both phenotypes were associated with genetic liability to schizophrenia. CONCLUSIONS: Schizotypy showed substantial between-sites variation, being more represented in areas where FEP incidence is higher. This supports the hypothesis that shared contextual factors shape the between-sites variation of psychosis across the spectrum.
KW - incidence of psychosis
KW - psychosis epidemiology
KW - psychosis prevention
KW - psychosis spectrum
KW - psychotic experiences
KW - schizotypy
KW - subclinical psychosis
U2 - 10.1017/S0033291723003781
DO - 10.1017/S0033291723003781
M3 - Article
SN - 0033-2917
VL - 54
SP - 1810
EP - 1823
JO - Psychological Medicine
JF - Psychological Medicine
IS - 8
ER -