The profile of hippocampal metabolites differs between Alzheimer's disease and subcortical ischemic vascular dementia, as measured by proton magnetic resonance spectroscopy.
Alzheimer's disease (AD) and subcortical ischemic vascular dementia (SIVD) have overlapping pathologies and risk factors, but their underlying neurodegenerative mechanisms are basically different. We performed magnetic resonance spectroscopy (MRS) to study metabolite differences between the two diseases in vivo. The subjects were 31 patients with SIVD and 99 with AD. Additionally, 45 elderly subjects were recruited as controls. We measured N-acetylaspartate (NAA), glutamine and glutamate (Glx), and myoinositol (mIns) concentration quantitatively using a 1.5-T MR scanner. N-acetylaspartate and Glx concentrations decreased in the hippocampus and cingulate/precuneal cortices (PCC) in both AD and SIVD patients, and the NAA decrease in the hippocampus was more prominent in AD than in SIVD. Interestingly, the pattern of mIns concentration changes differed between the two disorders; mIns was increased in AD but not increased in SIVD. If one differentiates between AD and SIVD by the mIns concentration in the hippocampus, the area under the receiver operating characteristic curve was 0.95, suggesting a high potential for discrimination. Our results suggest that proton MRS can provide useful information to differentiate between AD and SIVD. The difference of mIns concentrations in the hippocampus and PCC seems to reflect the different neurodegenerative mechanisms of the two disorders.
Biomedical MR Science Center, Shiga University of Medical Science, Ohtsu, Shiga, Japan. shiino@belle.shiga-med.ac.jp
Akihiko
A
Shiino
Toshiyuki
T
Watanabe
Yoshitomo
Y
Shirakashi
Emi
E
Kotani
Masahiro
M
Yoshimura
Shigehiro
S
Morikawa
Toshiro
T
Inubushi
Ichiro
I
Akiguchi
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000378:metabolism* / Q000473:pathology; D000596:Amino Acids / Q000378:metabolism*; D002545:Brain Ischemia / Q000378:metabolism* / Q000473:pathology; D015140:Dementia, Vascular / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006624:Hippocampus / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007294:Inositol / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D008297:Male
D000596:Amino Acids; D007294:Inositol