Prevalence and clinical correlates of disinhibition in dementia.
OBJECTIVE
The phenomenology, main clinical correlates, and long-term evolution of disinhibition in dementia are not well known. To examine this issue, we studied a consecutive series of 272 patients with probable Alzheimer disease using a comprehensive psychiatric and neuropsychological evaluation that included the Disinhibition Scale. A subset of patients was reexamined with the same instruments between 1 and 4 years after the initial evaluation.


RESULTS
A factor analysis of the Disinhibition Scale demonstrated 4 factors: (1) abnormal motor behavior, (2) hypomania, (3) loss of insight and egocentrism, and (4) poor self-care. Disinhibition was significantly associated with major and dysthymic depression, more severe negative symptoms, and loss of awareness. Most patients with disinhibition at the initial evaluation still showed disinhibition at follow-up, whereas 23% of patients without disinhibition at the initial evaluation developed disinhibition at follow-up.


CONCLUSIONS
Disinhibition is a frequent and long-lasting problem in dementia. Our study demonstrates that the construct of disinhibition consists of 4 independent subsyndromes, each of which may have specific underlying mechanisms.
Starkstein
Sergio E
SE
School of Psychiatry and Clinical Neurosciences, University of Western Australia, and Fremantle Hospital, Fremantle, Australia. ses@cyllene.uwa.edu.au
Garau
M Laura
ML
Cao
Agustina
A
D000368:Aged; D000544:Alzheimer Disease / Q000150:complications* / Q000523:psychology*; D016022:Case-Control Studies; D003863:Depression; D005260:Female; D006801:Humans; D007266:Inhibition, Psychological; D008297:Male; D001523:Mental Disorders / Q000209:etiology; D008875:Middle Aged; D015995:Prevalence; D011569:Psychiatric Status Rating Scales