TY - JOUR
T1 - Association between symptom dimensions and categorical diagnoses of psychosis
T2 - A cross-sectional and longitudinal investigation
AU - Russo, Manuela
AU - Levine, Stephen Z.
AU - Demjaha, Arsime
AU - Di Forti, Marta
AU - Bonaccorso, Stefania
AU - Fearon, Paul
AU - Dazzan, Paola
AU - Pariante, Carmine M.
AU - David, Anthony S.
AU - Morgan, Craig
AU - Murray, Robin M.
AU - Reichenberg, Abraham
PY - 2014/1
Y1 - 2014/1
N2 - Context: Cross-sectional studies of the signs and symptoms of psychosis yield dimensional phenotypes. However, the validity and clinical utility of such dimensions remain debated. This study investigated the structure of psychotic symptomatology, the stability of the structure over time, and the concordance between symptom dimensions and categorical diagnoses.Methods: Sample consisted of 500 first-episode psychotic patients. A cross-sectional study (N = 500) investigated the organizational structure of symptom dimensions at the onset of psychosis and its concordance with categorical diagnoses; next, a nested longitudinal study (N = 100) examined the stability of the symptom dimensions structure after 5-10 years of follow-up.Results: Factor analyses identified 6 first-order factors (mania, negative, disorganization, depression, hallucinations, and delusions) and 2 high-order factors (affective and nonaffective psychoses). Cumulative variance accounted for by the first and high-order factors was 63%: 31% by the first-order factors and 32% by the high-order factors. The factorial structure of psychotic symptoms during first episode remained stable after 5-10 years of follow-up. The overall concordance between 4 categorical diagnostic groups (schizophrenia, mania with psychosis, psychotic depression and schizoaffective disorder) and dimensional symptom ranged from 62.2% to 73.1% (when the schizoaffective group was excluded).Conclusions: Symptoms of psychosis assume a multidimensional hierarchical structure. This hierarchical model was stable over time and showed good concordance with categorical diagnoses. The combined use of dimensional and categorical approach to psychotic disorders would be of clinical and research utility.
AB - Context: Cross-sectional studies of the signs and symptoms of psychosis yield dimensional phenotypes. However, the validity and clinical utility of such dimensions remain debated. This study investigated the structure of psychotic symptomatology, the stability of the structure over time, and the concordance between symptom dimensions and categorical diagnoses.Methods: Sample consisted of 500 first-episode psychotic patients. A cross-sectional study (N = 500) investigated the organizational structure of symptom dimensions at the onset of psychosis and its concordance with categorical diagnoses; next, a nested longitudinal study (N = 100) examined the stability of the symptom dimensions structure after 5-10 years of follow-up.Results: Factor analyses identified 6 first-order factors (mania, negative, disorganization, depression, hallucinations, and delusions) and 2 high-order factors (affective and nonaffective psychoses). Cumulative variance accounted for by the first and high-order factors was 63%: 31% by the first-order factors and 32% by the high-order factors. The factorial structure of psychotic symptoms during first episode remained stable after 5-10 years of follow-up. The overall concordance between 4 categorical diagnostic groups (schizophrenia, mania with psychosis, psychotic depression and schizoaffective disorder) and dimensional symptom ranged from 62.2% to 73.1% (when the schizoaffective group was excluded).Conclusions: Symptoms of psychosis assume a multidimensional hierarchical structure. This hierarchical model was stable over time and showed good concordance with categorical diagnoses. The combined use of dimensional and categorical approach to psychotic disorders would be of clinical and research utility.
KW - DSM-5
KW - diagnostic classification
KW - longitudinal study
KW - psychosis
KW - symptom dimensions
UR - http://www.scopus.com/inward/record.url?scp=84892651367&partnerID=8YFLogxK
U2 - https://doi.org/10.1093/schbul/sbt055
DO - https://doi.org/10.1093/schbul/sbt055
M3 - Article
C2 - 23661632
SN - 0586-7614
VL - 40
SP - 111
EP - 119
JO - Schizophrenia Bulletin
JF - Schizophrenia Bulletin
IS - 1
ER -