Cluster analysis of symptoms in elderly demented patients.

Many elderly patients with organic brain syndrome are admitted to psychiatric hospitals, where they make up approximately 30 per cent of the resident popu lation (Ballinger et a!, 1981). The psychiatric in patients are a selected group and most demented people are in the community (Kay et al, 1964) and other hospitals. Most patients are diagnosed as suffering fromsenile orarteriosclerotic dementiand it is claimed that these conditions can be differen tiatedon clinical grounds(Hachinski eta!,1975), although in practice this may be difficult. A grouping within the senile dementia diagnosis is less clear although the mental disorder section of the Inter national aassification of Diseases describes senile dementia (simple type 290.0) and differentiates senile dementia depressed or paranoid type (290.2) as well as senile dementia with acute confusional state (290.4). Verwoerdt (1976) discussed a grouping of senile dementia into simple dementia, delirious dementia, depressed type, paranoid type and presbyophrenia (with confabulation). Wertheimer (1974) divided senile dementia into simple, hypochondriacal, melan cholic, manic-expansive and paranoid-hallucinatory types. In a previous study using cluster analysis we found