title: Magnetic resonance spectroscopy and cognitive function in healthy elderly men.
abstract: Subtle cognitive decrements in older people are important in terms of the associated morbidity and as a risk factor for dementia. However, their pathophysiological basis is poorly understood. Proton magnetic resonance spectroscopy ((1)H-MRS) may provide the means to investigate early changes in brain metabolite concentrations. We examined the relationships between N-acetylaspartate (NAA), choline (Cho) and creatine (Cr) metabolite ratios in a voxel in the parietal cortex and cognitive function in 88 healthy, non-demented, unmedicated men aged 65-70 years. We also used linear regression to give a value for each metabolite adjusted for the levels of the other two metabolites. Both NAA/Cr and Cho/Cr ratios correlated positively with tests of verbal memory and a verbal memory factor (e.g. NAA/Cr and Logical Memory: r = 0.24, P < 0.05). Cho/Cr ratios also correlated positively with tests of visual memory (e.g. visual reproduction: r = 0.21, P < 0.05). Adjusted Cr levels correlated negatively and significantly with tests of verbal memory and the Verbal Memory Factor. The regression analysis suggested that Cr levels better explained the correlations between NAA/Cr and Cho/Cr ratios and cognitive variables than NAA or Cho levels. These results suggest that in healthy men aged 65-70 years, metabolite levels relate to cognitive performance. Rising Cr levels may be an early marker of cognitive decline.
authors.affiliation: Brain Imaging Research Centre for Scotland, Edinburgh, UK.
authors.forename: Karen J
authors.initials: KJ
authors.lastname: Ferguson
authors.forename: Alasdair M J
authors.initials: AM
authors.lastname: MacLullich
authors.forename: Ian
authors.initials: I
authors.lastname: Marshall
authors.forename: Ian J
authors.initials: IJ
authors.lastname: Deary
authors.forename: John M
authors.initials: JM
authors.lastname: Starr
authors.forename: Jonathan R
authors.initials: JR
authors.lastname: Seckl
authors.forename: Joanna M
authors.initials: JM
authors.lastname: Wardlaw
mesh_terms: D000368:Aged; D003071:Cognition / Q000502:physiology*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods* / Q000706:statistics & numerical data; D008297:Male; D010296:Parietal Lobe / Q000378:metabolism / Q000502:physiology*; D011522:Protons
chemical_list: D011522:Protons