Decreased cortical glucose metabolism in converters from CDR 0.5 to Alzheimer's disease in a community: the Osaki-Tajiri Project.
BACKGROUND
Several follow-up [18F]fluorodeoxy glucose (FDG)-positron emission tomography (PET) studies have been performed in patients with mild cognitive impairment, but none have examined subjects with a Clinical Dementia Rating (CDR) of 0.5. Therefore, we used FDG-PET to investigate whether baseline glucose metabolism (CMRglc) in CDR 0.5 converters to dementia showed changes consistent with early Alzheimer's disease (AD).


METHODS
Based on our earlier study, which we refer to as Prevalence Study 1998, we were able to examine 14 CDR 0, 42 CDR 0.5, and 12 AD subjects with PET and follow these subjects for five years. Baseline neuropsychological and CMRglc values were compared among groups of CDR 0, CDR 0.5/converters, CDR 0.5/non-converters, and AD subjects.


RESULTS
All CDR 0 subjects were reassessed as CDR 0 after the five-year period. For CDR 0.5 subjects, 20 had converted to AD and 22 remained as CDR 0.5. In cognitive tests, CDR 0.5/converters showed significantly deteriorated recent memory function compared with CDR 0.5/non-converters at the baseline evaluation. Most brain areas showed decreased CMRglc in AD patients. CDR 0.5/converters had a significantly lower baseline CMRglc in the right cingulate, left inferior parietal and left temporal gyrus compared with CDR 0.5/non-converters.


CONCLUSIONS
Our findings suggest that CDR 0.5/converters have a baseline metabolic decline in areas that might be specific to AD.
Ishii
Hiroshi
H
Department of Geriatric Behavioral Neurology, Tohoku University Graduate School of Medicine, Sendai, Japan.
Ishikawa
Hiroyasu
H
Meguro
Kenichi
K
Tashiro
Manabu
M
Yamaguchi
Satoshi
S
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000000981:diagnostic imaging*; D001786:Blood Glucose / Q000378:metabolism*; D001921:Brain / Q000000981:diagnostic imaging; D003072:Cognition Disorders / Q000000981:diagnostic imaging*; D018450:Disease Progression; D004292:Dominance, Cerebral / Q000502:physiology; D004734:Energy Metabolism / Q000502:physiology; D005260:Female; D019788:Fluorodeoxyglucose F18; D006179:Gyrus Cinguli / Q000000981:diagnostic imaging; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D007564:Japan; D008279:Magnetic Resonance Imaging; D008297:Male; D008609:Mental Status Schedule / Q000706:statistics & numerical data; D009483:Neuropsychological Tests / Q000706:statistics & numerical data*; D010296:Parietal Lobe / Q000000981:diagnostic imaging; D049268:Positron-Emission Tomography; D011594:Psychometrics; D012016:Reference Values; D013702:Temporal Lobe / Q000000981:diagnostic imaging
D001786:Blood Glucose; D019788:Fluorodeoxyglucose F18