Predominant left hemisphere metabolic dysfunction in dementia
D. A. Loewenstein, W. W. Barker, J. Y. Chang, A. Apicella, F. Yoshii, P. Kothari, B. Levin and R. Duara
Wien Center for Alzheimer's Disease and Memory, Mount Sinai Medical Center, Miami Beach, FL 33140.
Thirty-one patients with probable Alzheimer's disease and 11 patients with
memory disorders, attributable to multiple cerebral infarctions, were
studied using 18-F-fluorodeoxyglucose-positron emission tomography scans.
Asymmetry in cerebral glucose metabolism within these diagnostic groups was
assessed by comparison with the metabolic rates obtained in age-equivalent
healthy control subjects. A significantly greater number of individuals in
both patient groups exhibited predominant left rather than right hemisphere
hypometabolism. In addition, for patients with Alzheimer's disease, the
degree of asymmetry was not related to either the severity or duration of
dementia. These findings could be explained by greater susceptibility of
the left hemisphere to degenerative or ischemic brain disease, by a
specific sampling effect, or most likely, by greater metabolic deficits
resulting from left rather than right hemisphere impairment.
