Fluoro-deoxy-glucose positron emission tomography correlates of impaired activities of daily living in dementia with Lewy bodies: implications for cognitive reserve.
OBJECTIVE
1) To investigate the neural substrate of impaired activities of daily living (ADL) in dementia with Lewy bodies (DLB) and 2) to explore, in the context of cognitive reserve, if hypometabolism was more pronounced in well-educated patients at the same level of everyday impairment.


METHODS
Twenty-one patients with DLB underwent an extensive clinical evaluation including cerebral positron emission tomography with F-fluoro-2-deoxy-glucose scanning. First, brain areas were identified, where ADL performance and glucose metabolism were significantly correlated, controlling for individual differences in cognitive and motor dysfunction. Second, it was tested if there was a significant negative association between metabolism and years of education in brain regions associated with ADL performance. Again, a correction for cognitive and motor impairment was deployed.


RESULTS
There was a significant association between glucose hypometabolism and impaired ADL performance in an extensive brain cluster located in the right temporoparietal cortex. Furthermore, schooling and metabolic rate were inversely associated in the right Brodmann area 19, controlling for ADL performance.


CONCLUSIONS
The study suggests that 1) certain brain metabolic alterations are specifically associated with the loss of everyday competence, even if differences in cognition and motor function are taken into consideration and 2) well-educated patients can offset more brain damage until reaching the same degree of ADL impairment as their less educated counterparts. These results extend the literature on cognitive reserve to a region-specific effect on ADL performance.
Perneczky
Robert
R
Departments of Psychiatry and Psychotherapy, Technical University Munich, Ismaninger Strasse 22, Munich, Germany. robert.perneczky@lrz.tum.de
Häussermann
Peter
P
Drzezga
Alexander
A
Boecker
Henning
H
Granert
Oliver
O
Feurer
Regina
R
Förstl
Hans
H
Kurz
Alexander
A
D000203:Activities of Daily Living / Q000523:psychology*; D000368:Aged; D000369:Aged, 80 and over; D001786:Blood Glucose / Q000378:metabolism; D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism; D003071:Cognition / Q000502:physiology*; D003704:Dementia / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000503:physiopathology*; D004522:Educational Status; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007091:Image Processing, Computer-Assisted; D020961:Lewy Body Disease / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D049268:Positron-Emission Tomography / Q000379:methods; D019275:Radiopharmaceuticals; D012044:Regression Analysis
D001786:Blood Glucose; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18