Anosognosia in very mild Alzheimer's disease but not in mild cognitive impairment.
OBJECTIVE
To study awareness of cognitive dysfunction in patients with very mild Alzheimer's disease (AD) and subjects with mild cognitive impairment (MCI).


METHODS
A complaint interview covering 13 cognitive domains was administered to 82 AD and 79 MCI patients and their caregivers. The patient groups were comparable according to age and education, and Mini Mental State Examination (MMSE) scores were > or =24 in all cases. The discrepancy between the patients' and caregivers' estimations of impairments was taken as a measure of anosognosia.


RESULTS
Self-reports of cognitive difficulties were comparable for AD and MCI patients. However, while in comparison to caregivers MCI patients reported significantly more cognitive impairment (p < 0.05), AD patients complained significantly less cognitive dysfunctions (p < 0.001).


CONCLUSIONS
While most MCI patients tend to overestimate cognitive deficits when compared to their caregiver's assessment, AD patients in early stages of disease underestimate cognitive dysfunctions. Anosognosia can thus be regarded as a characteristic symptom at a stage of very mild AD (MMSE > or =24) but not MCI. Accordingly, medical history even in mildly affected patients should always include information from both patient and caregiver.
Kalbe
E
E
Department of Neurology, University Hospital, and Max Planck Institute for Neurological Research, Cologne, Germany. Elke.Kalbe@pet.mpin-koeln.mpg.de
Salmon
E
E
Perani
D
D
Holthoff
V
V
Sorbi
S
S
Elsner
A
A
Weisenbach
S
S
Brand
M
M
Lenz
O
O
Kessler
J
J
Luedecke
S
S
Ortelli
P
P
Herholz
K
K
D000368:Aged; D000369:Aged, 80 and over; D000377:Agnosia / Q000175:diagnosis* / Q000209:etiology; D000544:Alzheimer Disease / Q000150:complications / Q000175:diagnosis*; D003072:Cognition Disorders / Q000150:complications / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008297:Male; D008487:Medical History Taking; D008875:Middle Aged; D012044:Regression Analysis; D012720:Severity of Illness Index