Factors associated with psychotic symptoms in Alzheimer's disease.
OBJECTIVE
Many clinical and biological factors have been reported to be associated with the presence of psychosis in patients with Alzheimer'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 results 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 genotype were investigated for dichotomous psychotic status with a multiple logistic regression analysis.


RESULTS
Of the 228 patients with Alzheimer's disease, 118 (51.8%) showed evidence of delusions or hallucinations. Of these, 94 had delusions only, three had hallucinations only, and 21 had both. Older age, female sex, longer duration of illness, and more severe cognitive impairment were the factors independently associated with the presence of psychosis. The presence of psychosis was not significantly related to either educational level or apolipoprotein E genotype.


CONCLUSIONS
Age, sex, and severity of illness were independent 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.
Hirono
N
N
Division of Clinical Neurosciences, Hyogo Institute for Aging Brain and Cognitive Disorders, Himeji, Japan. hirono@hiabcd.go.jp
Mori
E
E
Yasuda
M
M
Ikejiri
Y
Y
Imamura
T
T
Shimomura
T
T
Ikeda
M
M
Hashimoto
M
M
Yamashita
H
H
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000175:diagnosis* / Q000235:genetics / Q000523:psychology; D053327:Apolipoprotein E4; D001057:Apolipoproteins E / Q000235:genetics; D003702:Delusions / Q000175:diagnosis / Q000235:genetics / Q000523:psychology; D005260:Female; D005838:Genotype; D006212:Hallucinations / Q000175:diagnosis / Q000235:genetics / Q000523:psychology; D006801:Humans; D008297:Male; D008875:Middle Aged; D019965:Neurocognitive Disorders / Q000175:diagnosis* / Q000235:genetics / Q000523:psychology; D009483:Neuropsychological Tests; D016017:Odds Ratio; D012044:Regression Analysis; D012307:Risk Factors
D053327:Apolipoprotein E4; D001057:Apolipoproteins E