Clinical profiles of dementia with Lewy bodies with and without Alzheimer's disease-like hypometabolism.
OBJECTIVE
It is well known that Alzheimer's disease (AD)-type pathology is commonly present in dementia with Lewy bodies (DLB) brains and that the degree of AD-type pathology has an influence on the clinical characteristics of DLB. Although significant hypometabolism in the temporoparietal/precuneus on [(18)F]fluoro-d-glucose ((18)F-FDG) positron emission tomography (PET) scans is considered to support a diagnosis of AD, some DLB patients also exhibit this metabolic pattern. The clinical significance of the metabolic pattern on DLB remains unknown.


METHODS
Twenty-three DLB patients, 10 AD patients, and 11 controls underwent (18)F-FDG PET scans. According to the degree of hypometabolism in the parietal/precuneus regions, representing the AD-like metabolic pattern, 12 patients were placed in the DLB-AD(+) group and 11 patients were placed in the DLB-AD(-) group. The demographics and clinical variables were compared among the four groups.


RESULTS
In addition to the parietal/precuneus regions, the DLB-AD(+) group exhibited significantly greater posterior cingulate hypometabolism than the DLB-AD(-) group, although occipital metabolism did not differ. The prevalence of visual hallucinations and extracampine hallucinations, and the Bender-Gestalt test score were significantly higher in the DLB-AD(+) group than the DLB-AD(-) group, although there were no differences in the demographics and other examined clinical variables between the two DLB groups. These clinical differences were absent in the DLB-AD(-) group, AD group, and controls.


CONCLUSIONS
Parietal/precuneus hypometabolism may be associated with clinical characteristics in DLB patients. Further multiple imaging modalities that are sensitive to AD-type pathology are needed to reveal the neurobiological basis of the AD-like metabolic pattern.
PET/CT Dementia Research Center, Juntendo Tokyo Koto Geriatric Medical Center, Juntendo University School of Medicine, Tokyo, Japan; Department of Psychiatry, Juntendo University School of Medicine, Tokyo, Japan; Department of Psychiatry, Yokohama City University School of Medicine, Kanagawa, Japan.
Yuhei
Y
Chiba
Hiroshige
H
Fujishiro
Kazumi
K
Ota
Koji
K
Kasanuki
Heii
H
Arai
Yoshio
Y
Hirayasu
Kiyoshi
K
Sato
Eizo
E
Iseki
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology / Q000523:psychology; D000704:Analysis of Variance; D001921:Brain / Q000378:metabolism*; D016022:Case-Control Studies; D005260:Female; D019788:Fluorodeoxyglucose F18; D005947:Glucose / Q000378:metabolism; D006212:Hallucinations / Q000523:psychology; D006801:Humans; D020961:Lewy Body Disease / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000523:psychology; D008297:Male; D008875:Middle Aged; D009778:Occipital Lobe / Q000378:metabolism; D010296:Parietal Lobe / Q000378:metabolism; D049268:Positron-Emission Tomography / Q000379:methods
D019788:Fluorodeoxyglucose F18; D005947:Glucose
DLB; FDG PET; Parkinson's disease; cerebral metabolism; extracampine hallucination; visual hallucination