FACTORS ASSOCIATED WITH PSYCHOTIC SYMPTOMS IN ALZHEIMERS-DISEASE

Objectives-Many clinical and biological factors have been reported to be associated with the presence of psychosis in patients with Alzheime r's disease, although the associations were variable. The aim of this study was to clarify factors associated with the presence of psychosis in patients with Alzheimer's disease. Methods-Psychiatric functioning was studied in 228 patients with Alzheimer's disease based on the res ults of the behavioural pathology in Alzheimer's disease rating scale or the neuropsychiatric inventory. The effects of sex, education level , age, duration of illness, cognitive function, and apolipoprotein E g enotype were investigated for dichotomous psychotic status with a mult iple logistic regression analysis. Results-Of the 228 patients with Al zheimer's disease, 118 (51.8%) showed evidence of delusions or halluci nations. Of these, 94 had delusions only, three had hallucinations onl y, and 21 had both. Older age, female sex, longer duration of illness, and more severe cognitive impairment were the factors independently a ssociated with the presence of psychosis. The presence of psychosis wa s not significantly related to either educational level or apolipoprot ein E genotype. Conclusions-Age, sex, and severity of illness were ind ependent factors associated with the presence of psychosis in patients with Alzheimer's disease. The reason why some patients with Alzheimer 's disease develop psychosis remains unclear. There may be distinctive subtypes of Alzheimer's disease or the presence of individual factors which affect the development of psychosis.