IC-P-047

Increased age, the Apo–E4 allele, poor cognitive performance, and reduced brain glucose metabolism are well–established risk factors for Alzheimer's disease (AD) and mild cognitive impairment (MCI). Little is known about these relationships in normal (NL) aging. To examine in the NL adult lifespan, the relationships between age, cognitive performance, and brain glucose metabolism (MRglc, μmol/g/min). In addition, we examined whether these relationship were affected by Apo–E genotype. We hypothesized that increasing age would be associated with a pattern of widespread MRglc reductions and greater cognitive impairments. Specifically, hippocampal and prefrontal MRglc would be associated with memory and attention tests, respectively. We also hypothesized that the presence of the Apo–E4 genotype would negatively impact MRglc and cognition. 92 NL subjects (22–90 years, MMSE 28, 73% female, 20% E–4+, education 12 years) received clinical, neuropsychological, MRI, and Positron Emission Tomography (FDG–PET) examinations. Using an automated template we examined MRglc in 9 brain regions: hippocampus, amygdala, inferior parietal lobule, whole temporal lobe, posterior cingulate cortex, orbital frontal and prefrontal cortex, occipital cortex, and thalamus. MRI based atrophy correction was applied to all PET scans. Pons MRglc was used to correct for inter–subject variability. Linear regression analyses were used to examine relationships between MRglc in brain regions with age, cognitive performance, and Apo–E genotype. Negative linear correlations between age and MRglc were found in all brain regions (R2's ranging from –.30 to –.60, Pearson's p's .001), greatest in the prefrontal cortex. Negative correlations between age and cognition were also found (R2's ranging from –.26 to –.56 Pearson's p's .01). ApoE genotype did not differentially affect either cognitive performance or the regional MRglc (p's> .05). Memory was predicted by both hippocampal and prefrontal MRglc, (R2=.23, p's