title: The effects of prolonged stress and APOE genotype on memory and cortisol in older adults.
abstract: BACKGROUND
  Chronic elevations in cortisol associated with prolonged stress have been associated with memory loss, as has the apolipoprotein E gene (APOE-epsilon4) genotype. Combined effects of stress and APOE status on memory and cortisol in humans have not been studied.
  
  
  METHODS
  A semistructured interview with standardized scoring was used to measure stress level and univariate analysis of variance to assess effects of stress and APOE-epsilon4 status on memory and salivary cortisol in 91 nondemented subjects (mean age 78.8 years).
  
  
  RESULTS
  Low-stress subjects performed better than high-stress subjects on delayed recall of stories (p = .04), word lists (p = .02), and visual designs (p = .04). APOE-epsilon4-negative subjects obtained better scores than epsilon4-positive subjects on immediate (p = < .01) and delayed (p < .01) recall of visual designs. Significant stress by APOE-epsilon4 interaction effects on memory (p = .03) and cortisol (p < .01) resulted from consistently worse memory and higher cortisol concentrations in the high stress, epsilon4-positive group.
  
  
  CONCLUSIONS
  These findings are consistent with a model in which prolonged exposure of older, nondemented individuals to stress in the presence of an epsilon4 allele leads to memory decline. Further studies will assess whether stress and APOE-epsilon4 interact to increase the risk of developing Alzheimer's disease.
authors.affiliation: Department of Neurosciences, University of California, San Diego, California, USA. gpeavy@ucsd.edu
authors.forename: Guerry M
authors.initials: GM
authors.lastname: Peavy
authors.forename: Kelly L
authors.initials: KL
authors.lastname: Lange
authors.forename: David P
authors.initials: DP
authors.lastname: Salmon
authors.forename: Thomas L
authors.initials: TL
authors.lastname: Patterson
authors.forename: Sherry
authors.initials: S
authors.lastname: Goldman
authors.forename: Anthony C
authors.initials: AC
authors.lastname: Gamst
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Mills
authors.forename: Srikrishna
authors.initials: S
authors.lastname: Khandrika
authors.forename: Douglas
authors.initials: D
authors.lastname: Galasko
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001057:Apolipoproteins E / Q000235:genetics*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D005838:Genotype; D015577:Geriatric Assessment; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D008297:Male; D008568:Memory / Q000502:physiology*; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D012463:Saliva / Q000378:metabolism; D013315:Stress, Psychological / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology
chemical_list: D001057:Apolipoproteins E; D006854:Hydrocortisone