[Identification by typological analysis of distinct groups of schizophrenic patients. Applicability of a disorganized schizophrenia subtype].
Since Crow, Andreasen et al. have described schizophrenia in terms of negative and positive symptoms, the dichotomic approach has been well established. As a matter of fact, factor analyses, especially principal components analyses, led with symptomatic specific scales, have proved their validity. But they have shown their limits too : some authors think that the dichotomic model fails to explain all of the schizophrenic psychopathology and that a third dimension including formal thought disorders, most of the time called "disorganization", should systematically be taken into account. In this study, the authors have hypothesized that a categorial approach could describe this "disorganization". Using a cluster analysis they investigated the existence of subtypes in a population including 136 schizophrenic patients assessed with the PANSS (Positive and Negative Syndrome Scale, Kayet al., 1987). The results suggested at least five subtypes: a pure positive subtype, characterized by high scores on items delusions, hallucinatory behavior, suspiciousness/persecution, and by a low score on conceptual disorganization item; a disorganized positive subtype, characterized by high scores on positive items, including conceptual disorganization item, and also high scores on unusual thought content and autistic preoccupation items; a negative subtype, characterized by high scores on negative items and low scores on positive items, including conceptual disorganization item; a mixed subtype, characterized by high scores on the most positive, negative and general psychopathological items; a residual subtype, characterized by low scores on all the positive, negative and general psychopathological items. The good validity of this analysis was showed since differences on a number of clinical characteristics were observed between the five clusters. These results demonstrated the oversimplication of the positive-negative dichotomy and the relevance of a disorganized subtype.
Brazo
P
P
Centre Esquirol, CHU Côte-de-Nacre, Caen.
Ribeyre
J M
JM
Petit
M
M
Dollfus
S
S
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016000:Cluster Analysis; D015331:Cohort Studies; D003866:Depressive Disorder / Q000145:classification / Q000175:diagnosis / Q000523:psychology; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data; D011594:Psychometrics; D015203:Reproducibility of Results; D012562:Schizophrenia, Disorganized / Q000145:classification* / Q000175:diagnosis / Q000523:psychology; D013850:Thinking
Identification par une analyse typologique de groupes distincts de patients schizophrènes. Pertinence d'un groupe désorganisé.