Magnetic resonance spectroscopy (MRS) noninvasively provides information on the concentration of some cerebral metabolites in vivo. Among those measurable by
proton magnetic resonance spectroscopy (1H-MRS),
N-acetyl-aspartate (NAA) is decreased, and myo-
inositol (ml) and
choline (Cho) levels are increased in patients with
Alzheimer's disease (AD).
Donepezil, an acetylcholinesteraze inhibitor, has proven effect on
cognitive symptoms in patients with AD. In previous studies, treatment response was associated with an increase of NAA and NAA/Cr in the parietal lobe and hippocampi. Correlation of longitudinal changes of 1H-MRS detectable metabolites in dorsolateral prefrontal cortex (DLPFC) with clinically observable changes is a poorly researched topic. The objective of this non-interventional study is to assess whether changes in 1H-MRS measurable metabolites correlate with clinical outcome after
donepezil treatment. Twelve patients with mild to moderate AD were evaluated during 26 weeks of
donepezil treatment. 1H-MRS parameters in DLPFC were assessed before and after 26 weeks of
donepezil treatment. Cognition was assessed with
Alzheimer's Disease Assessment Scale cognitive subscale (ADAS-Cog). A significant increase in NAA/Cr ratio and significantly lower decrease in mI/Cr ratio were found in AD patients with positive treatment response. The results of this study indicate possible modest
donepezil effect on prevention of neuronal functional deterioration in DLPFC which correlates with clinical outcome and point the use of 1HMRS as technique of help in assessment of
drug effect.