Am J Psychiatry 1995; 152:1458-1463
Copyright © 1995 by American Psychiatric Association
Negative, psychoticism, and disorganized dimensions in patients with familial schizophrenia or bipolar disorder: continuity and discontinuity between the major psychoses
M Maziade, MA Roy, M Martinez, D Cliche, JP Fournier, Y Garneau, L Nicole, N Montgrain, C Dion and AM Ponton
Centre de recherche, Universite Laval Robert-Giffard, Quebec, Canada.
OBJECTIVE: This study aimed to answer the following questions: 1) Can we
reliably measure the psychopathologic dimensions of schizophrenia by using
a lifetime frame and by rating acute and interepisode periods separately?
2) Can we reproduce in subjects with familial schizophrenia the
characteristic three-factor structure of schizophrenic symptoms that has
been found previously in general groups of schizophrenic patients? 3) Is
the factor structure also present in familial bipolar disorder? METHOD:
Lifetime measures of psychotic symptoms were taken through a slightly
modified version of the Comprehensive Assessment of Symptoms and History
for 138 patients with highly familial DSM-III-R schizophrenia (N = 51),
bipolar disorder (N = 44), or spectrum disorders (N = 43). Symptoms were
rated separately in the acute episodes and in the stabilized interepisode
intervals across the patients' lives. RESULTS: A satisfactory level of
reliability was obtained. In this highly familial study group, the
positive/negative factorial distinction was replicated, as was a
three-factor model similar to that observed in prior general groups of
schizophrenic patients. These factors were also present in bipolar
affective disorder. The negative, psychoticism, and disorganized factor
model applied more to the acute phase of illness than to the stabilized
state. CONCLUSIONS: These findings offer an empirical basis for testing
biological or genetic variables in relation to negative/positive symptom
dimensions, rather than diagnoses. Observations of a shared structure for
schizophrenia and bipolar disorder suggest some continuity in the causes of
these disorders.
