title: MR spectroscopy for assessment of memantine treatment in mild to moderate Alzheimer dementia.
abstract: OBJECTIVE
  Magnetic Resonance Spectroscopy (MRS) may provide a precise and reliable assessment of the extent and severity of neural tissue loss caused by various diseases. In particular, the N-Acetyl Aspartate (NAA) and Creatine (Cr) ratio has been found to be an indicator of the degree of neuronal loss in Alzheimer's disease (AD). Memantine is thought to benefit the AD brain by stabilizing the NMDA receptors on neurons in turn reducing excitotoxicity. Despite its effectiveness in treating moderate to severe AD, memantine has not had similar success in the treatment of mildly demented AD patients. The objective of this study was to test whether memantine would slow or prevent the loss of neurons in mild to moderate AD patients.
  
  
  METHODS
  A double-blind placebo-controlled study was designed to measure the effect of a year-long course of memantine in patients with a probable AD diagnosis with mild to moderate dementia. The primary outcome measure was stipulated to be change in MRS NAA/Cr ratio in inferior parietal cortex in memantine relative to the placebo treatment condition. The secondary outcome measures were changes in cognitive and function scale scores.
  
  
  RESULTS
  This pilot study failed to demonstrate a benefit of memantine on the primary outcome measure, the inferior parietal NAA/Cr ratio, or the secondary outcome measures.
  
  
  CONCLUSIONS
  More studies are needed to determine the effect of memantine on regions of the brain significantly affected by AD pathology.
authors.affiliation: War Related Illness and Injury Study Center, VA Palo Alto Health Care System, Palo Alto, CA, USA. ashford@stanford.edu
authors.forename: J W
authors.initials: JW
authors.lastname: Ashford
authors.forename: M
authors.initials: M
authors.lastname: Adamson
authors.forename: T
authors.initials: T
authors.lastname: Beale
authors.forename: D
authors.initials: D
authors.lastname: La
authors.forename: B
authors.initials: B
authors.lastname: Hernandez
authors.forename: A
authors.initials: A
authors.lastname: Noda
authors.forename: A
authors.initials: A
authors.lastname: Rosen
authors.forename: R
authors.initials: R
authors.lastname: O'Hara
authors.forename: J K
authors.initials: JK
authors.lastname: Fairchild
authors.forename: D
authors.initials: D
authors.lastname: Spielman
authors.forename: J A
authors.initials: JA
authors.lastname: Yesavage
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000175:diagnosis / Q000188:drug therapy / Q000378:metabolism; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D001931:Brain Mapping; D003401:Creatine / Q000378:metabolism; D004311:Double-Blind Method; D018691:Excitatory Amino Acid Antagonists / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008559:Memantine / Q000627:therapeutic use*; D009483:Neuropsychological Tests; D010865:Pilot Projects
chemical_list: D018691:Excitatory Amino Acid Antagonists; D001224:Aspartic Acid; C000179:N-acetylaspartate; D003401:Creatine; D008559:Memantine