title: Differential cross-sectional and longitudinal impact of APOE genotype on hippocampal volumes in nondemented older adults.
abstract: OBJECTIVE
  Because of conflicting findings across studies, we sought to better determine the relationship between apolipoprotein E (APOE) genotype, hippocampal volume, and cognitive performance in nondemented older adults.
  
  
  METHODS
  Two groups ofolder adults, as determined by their APOE epsilon4 allele status, received structural MRI and comprehensive neuropsychological testing on two occasions separated on average by 17 months.
  
  
  RESULTS
  Cross-sectional comparisons by APOE group revealed no differences in hippocampal volumes, although longitudinal percent reduction in hippocampal volume was significantly greater for those possessing the APOE epsilon4 allele. Relationship between hippocampal volumes and memory performance was strongly impacted by diagnosis of mild cognitive impairment.
  
  
  CONCLUSIONS
  APOE epsilon4 allele appears to significantly impact rate of volume loss over time in the hippocampus in nondemented older adults, and detailed cognitive characterization of the sample is necessary to reliably interpret the relationship between cognition and brain structure.
authors: Veteran's Medical Research Foundation, San Diego, CA 92161, USA.
authors: Amy J
authors: AJ
authors: Jak
authors: Wes S
authors: WS
authors: Houston
authors: Bonnie J
authors: BJ
authors: Nagel
authors: Jody
authors: J
authors: Corey-Bloom
authors: Mark W
authors: MW
authors: Bondi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D053327:Apolipoprotein E4 / Q000235:genetics* / Q000502:physiology; D001921:Brain / Q000033:anatomy & histology; D003071:Cognition / Q000502:physiology*; D003430:Cross-Sectional Studies; D003627:Data Interpretation, Statistical; D005260:Female; D006624:Hippocampus / Q000033:anatomy & histology* / Q000473:pathology; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D009929:Organ Size; D012016:Reference Values
chemical_list: D053327:Apolipoprotein E4