Changes in cerebral glucose metabolism in patients with Parkinson’s disease with dementia after cholinesterase inhibitor therapy

OBJECTIVE: To evaluate changes in cerebral glucose metabolism in Parkinson’s disease dementia (PDD) patients after cholinesterase inhibitor therapy. BACKGROUND: Cholinesterase inhibitors (ChEI) are now widely used with proven efficacy in patients with PDD. There have been several reports describing how the drugs are benefiting the PDD patients in terms of clinical and neuropsychological scales. But there has never been a study on how the drug effect is represented on brain images. We performed serial 18FFDG PET studies in patients with PDD before and after ChEI therapy. METHOD: We investigated 11 patients with clinical diagnosis of PDD. Patients were treated with either donepezil or galantamine. End point was when patients were treated for at least 3 months and when the patient or family members reported improved cognition. 18F-FDG PET scan was done before initiation of treatment and after completion drug trial. SPM images were created by comparisons between groups on a voxel-by-voxel basis using paired tstatistics. RESULTS: Patients were treated for mean duration of 8.4±4.5 months. Cognitive testes done by MMSE showed improvement after ChEI therapy in 10 patients, especially on memory and serial 7 tasks. Mean improvement in MMSE score was 5.5 points. SPM analysis showed increased glucose metabolism in left superior / middle frontal gyrus and left inferior parietal gyrus, mainly angular gyrus. There was also a region of decreased glucose metabolism in right medial temporal cortex, including fusiform, parrahippocampal gyrus and hippocampus. The degree of improvement in MMSE score only correlated with degree of decreased glucose metabolism on right medial temporal cortex. DISCUSSION: Our study has shown that PDD patients treated with ChEI have increased glucose metabolism in left superior / middle frontal and inferior parietal cortices, and decreased metabolism in right medial temporal cortex. It would be interpreted as that it shows poor correlation with changes in cognitive domains in these patients, and bears little similarities with prior resting FDG-PET studies involving PDD patients. Similar pattern of metabolic changes have been demonstrated before in similarly designed studies with patients with Alzheimer’s disease. The authors conclude that ChEI therapy in PDD patients restores cognitive function by enhancing cholinergic neurotransmission in certain common areas regardless of the underlying pathologic process.

Author dc:creator

• 용, 석우

Contributors dc:contributor

• 주, 인수
• 대학원 의학과
• 104535

• 파킨슨병치매
• 콜린분해효소억제제
• 18F-FDG PET

Language dc:language

ko

Identifier

http://dcoll.ajou.ac.kr:9080/dcollection/jsp/common/DcLoOrgPer.jsp?sItemId=000000009156
000000009156

OAI identifier oai:identifier

oai:repository.ajou.ac.kr:201003/1803