Temporal lobe perfusion on single photon emission computed tomography predicts the rate of cognitive decline in Alzheimer's disease.
OBJECTIVE
To examine the ability of relative regional cerebral blood flow as measured by single photon emission computed tomography to predict longitudinal course of cognitive decline in Alzheimer's disease.


METHODS
Single photon emission computed tomography using the blood flow tracer 123I-N-isopropyl-p-iodoamphetamine was performed at initial evaluation and was used to predict the rate of cognitive decline over a follow-up period from 1 to 4 years.


METHODS
Outpatient university dementia clinic and center for functional imaging.


METHODS
Twenty-nine patients met National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association criteria for probably or possible AD.


RESULTS
Temporal lobe regional cerebral blood flow ratio at initial evaluation correlated with rate of decline in Mini-Mental State Examination over the longitudinal follow-up. Temporal regional cerebral blood flow ratio also predicted rate of decline of specific memory measures on the California Verbal Learning Test. Neither parietal nor frontal ratios predicted rate of cognitive decline. Dorsolateral frontal hypoperfusion was associated with the emergence of perseverative behaviors over time. Age, prior dementia duration, estimated prior rate of decline, and initial severity did not predict rate of cognitive decline.


CONCLUSIONS
Results suggest that regional perfusion on single photon emission computed tomography may predict cognitive decline in Alzheimer's disease better than these demographic and course variables.
Wolfe
N
N
Department of Neurology, University of California, Davis-Northern California Alzheimer's Disease Center, Berkeley.
Reed
B R
BR
Eberling
J L
JL
Jagust
W J
WJ
D000368:Aged; D000544:Alzheimer Disease / Q000150:complications* / Q000503:physiopathology*; D002560:Cerebrovascular Circulation; D003072:Cognition Disorders / Q000175:diagnosis* / Q000209:etiology*; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory; D013702:Temporal Lobe / Q000098:blood supply* / Q000000981:diagnostic imaging*; D015899:Tomography, Emission-Computed, Single-Photon