CLASSIFICATION OF PSYCHOTIC SYMPTOMS IN DEMENTIA SUFFERERS

Little attention has been payed to the classification of psychotic sym ptoms in dementia sufferers. This article compares the etiology of del usions, visual hallucinations and delusional misidentification and exa mines the value of factors generated from principal components analysi s as a possible classificatory system in a group of 125 patients with DSM-III-R dementia in contact with clinical services who were prospect ively evaluated using standardized instruments to describe in detail i ndividual psychotic symptoms. The assessment also included the Geriatr ic Mental State Schedule, the History and Aetiology Schedule and the C AMCOG. Delusions and visual hallucinations had a distinct cognitive pr ofile as did delusions and delusional misidentification, although ther e was an overlap between visual hallucinations and delusional misident ification. Four factors were generated from principal components analy sis. Three of these closely mirrored the 3 symptom groups delusions, v isual hallucinations and delusional misidentification, although the ph antom-boarder delusion was correlated with the visual hallucination fa ctor and not delusional misidentification. The fourth factor included visual hallucinations of relatives and delusions that relatives were i n the house. This factor was strongly inversely associated with emotio nal distress and could perhaps best be seen as a comfort phenomena. Th e pattern of cognitive deficits and etiological associations of each o f the factors were independent of one another, supporting the notion t hat it is useful to consider them as separate entities.