title: ApoE and pulse pressure interactively influence level and change in the aging of episodic memory: Protective effects among ε2 carriers.
abstract: OBJECTIVE
  We tested independent and interactive effects of Apolipoprotein E (ApoE) and pulse pressure (PP) concurrently and longitudinally across 9 years (3 waves) of episodic (EM) and semantic memory (SM) data from the Victoria Longitudinal Study.
  
  
  METHODS
  We assembled a sample of older adults (n = 570, baseline M age = 71, age range = 53-95) and used latent growth modeling to test 4 research goals.
  
  
  RESULTS
  First, the best fitting memory model was 2 single latent variables for EM and SM, each exhibiting configural, metric, and partial scalar invariance. This model was analyzed as a parallel process model. Second, baseline level of PP predicted EM performance at centering age (75) and rate of 9-year EM change. Third, we observed no main effects of ApoE on EM or SM. Fourth, EM was affected by higher PP but differentially less so for carriers of the ApoE ε2 allele than the ε3 or ε4 alleles.
  
  
  CONCLUSIONS
  PP is confirmed as a risk factor for concurrent and changing cognitive health in aging, but the effects operate differently across risk and protective allelic distribution of the ApoE gene.
authors.affiliation: Department of Psychology.
authors.forename: G Peggy
authors.initials: GP
authors.lastname: McFall
authors.affiliation: Department of Psychology.
authors.forename: Sandra A
authors.initials: SA
authors.lastname: Wiebe
authors.affiliation: Centre for Prions and Protein Folding Diseases.
authors.forename: David
authors.initials: D
authors.lastname: Vergote
authors.affiliation: Neuroscience and Mental Health Institute.
authors.forename: David
authors.initials: D
authors.lastname: Westaway
authors.affiliation: Centre for Prions and Protein Folding Diseases.
authors.forename: Jack
authors.initials: J
authors.lastname: Jhamandas
authors.affiliation: Karolinska Institutet.
authors.forename: Lars
authors.initials: L
authors.lastname: Bäckman
authors.affiliation: Department of Psychology.
authors.forename: Roger A
authors.initials: RA
authors.lastname: Dixon
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology / Q000523:psychology*; D000483:Alleles; D053329:Apolipoprotein E2 / Q000235:genetics*; D001794:Blood Pressure / Q000235:genetics*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D061212:Memory, Episodic; D008875:Middle Aged; D008960:Models, Psychological; D009483:Neuropsychological Tests; D012307:Risk Factors
chemical_list: D053329:Apolipoprotein E2