title: Five latent factors underlying schizophrenia: analysis and relationship to illnesses in relatives.
abstract: Clinical signs and symptoms in a sample of 1,043 individuals with schizophrenia or schizoaffective disorder were subjected to latent class factor analysis. Positive, negative, disorganized, and affective factors were similar in content to factors described in a number of other studies, while a fifth factor representing early onset/developmental signs provided a new area for investigation. The five sets of factor scores were logistically regressed on psychiatric illness indicators in first and second degree relatives. Relatives of probands with higher positive or negative symptom factor scores had a lower risk of depressive illness. Higher affective factor scores in probands predicted more mania and depression in relatives. Both the disorganized and the early onset/developmental factors were related to increased risk of psychiatric hospitalization in relatives, as well as increased risk of psychosis (marginally so for the disorganization factor). Increased early onset/developmental signs in the proband were also associated with increased risk for depression in relatives. These findings suggest a possible endophenotypic role for the factor scores in future studies.
authors.affiliation: Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA.
authors.forename: John A
authors.initials: JA
authors.lastname: McGrath
authors.forename: Gerald
authors.initials: G
authors.lastname: Nestadt
authors.forename: Kung-Yee
authors.initials: KY
authors.lastname: Liang
authors.forename: Virginia K
authors.initials: VK
authors.lastname: Lasseter
authors.forename: Paula S
authors.initials: PS
authors.lastname: Wolyniec
authors.forename: M Danielle
authors.initials: MD
authors.lastname: Fallin
authors.forename: Mary H
authors.initials: MH
authors.lastname: Thornquist
authors.forename: James R
authors.initials: JR
authors.lastname: Luke
authors.forename: Ann E
authors.initials: AE
authors.lastname: Pulver
mesh_terms: D000328:Adult; D017668:Age of Onset; D001714:Bipolar Disorder / Q000235:genetics; D003863:Depression / Q000235:genetics; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005163:Factor Analysis, Statistical; D005190:Family / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012559:Schizophrenia / Q000175:diagnosis* / Q000453:epidemiology / Q000235:genetics; D012565:Schizophrenic Psychology