Relationship of psychosis to aggression, apathy and function in dementia.
BACKGROUND
Psychosis has been associated with aggression in dementia, but the nature of this relationship has been unclear. There has been very little research into the relations between apathy and functional status to psychosis in dementia. The purpose of this study is to investigate the relationship between psychosis and aggression, apathy, and functional status in outpatients with dementia.


METHODS
The presence of psychosis was assessed by clinical interview and two scales: the Neuropsychiatric Inventory and the Columbia University Scale for Psychopathology in Alzheimer's Disease. The maximum likelihood estimation technique was used to determine the best estimate of the presence of psychosis. Aggression, apathy, and functional status (activities of daily living: ADLs) were measured using structured instruments.


RESULTS
Sixty-one subjects were included. The CUSPAD and NPI provided low false positive and negative rates. ANCOVA analyses showed that psychosis was significantly associated with aggression, even when controlling for apathy, depression, and ADLs. Psychosis was related to apathy only when depression was controlled for. Hallucinations were related to impaired basic ADLs, even when depression and apathy were controlled for.


CONCLUSIONS
Relationships were found between psychotic symptoms in dementia and aggression as well as apathy and impaired functional status. These relationships suggest pathophysiologic mechanisms and have possible treatment implications.
Department of Psychiatry, Sunnybrook and Women's College Health Sciences Centre, University of Toronto, 2075 Bayview Avenue, North York, Toronto, Ontario, Canada M4N 3MS.
M J
MJ
Rapoport
R
R
van Reekum
M
M
Freedman
D
D
Streiner
M
M
Simard
D
D
Clarke
T
T
Cohen
D
D
Conn
D000203:Activities of Daily Living; D000342:Affective Symptoms; D000368:Aged; D000374:Aggression; D003430:Cross-Sectional Studies; D003702:Delusions / Q000453:epidemiology; D003704:Dementia / Q000150:complications*; D005260:Female; D006212:Hallucinations / Q000453:epidemiology; D006801:Humans; D016013:Likelihood Functions; D008297:Male; D015999:Multivariate Analysis; D009864:Ontario / Q000453:epidemiology; D015995:Prevalence; D011618:Psychotic Disorders / Q000453:epidemiology / Q000209:etiology / Q000523:psychology*