Background. Psychosis has been associated with aggression in dementia, but
the nature of this relationship has been unclear. There has been very littl
e research into the relations between apathy and functional status to psych
osis in dementia. The purpose of this study is to investigate the relations
hip between psychosis and aggression, apathy, and functional status in outp
atients with dementia.
Methods. The presence of psychosis was assessed by clinical interview and t
wo scales: the Neuropsychiatric Inventory and the Columbia University Scale
for Psychopathology in Alzheimer's Disease. The maximum likelihood estimat
ion technique was used to determine the best estimate of the presence of ps
ychosis. Aggression, apathy, and functional status (activities of daily liv
ing: 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 wa
s significantly associated with aggression, even when controlling for apath
y, depression, and ADLs. Psychosis was related to apathy only when depressi
on 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 dementi
a and aggression as well as apathy and impaired functional status. These re
lationships suggest pathophysiologic mechanisms and have possible treatment
implications. Copyright (C) 2001 John Wiley & Sons, Ltd.