title: Role of APOE ε4 Allele and Incident Stroke on Cognitive Decline and Mortality.
abstract: The apolipoprotein E (APOE) ε4 allele and stroke increase the risk of cognitive decline. However, the association of the APOE ε4 allele before and after stroke is not well understood.
  
  
  
  Using a prospective sample of 3444 (66% African Americans, 61% females, mean age=71.9 y) participants, we examined cognitive decline relative to stroke among those with and without the APOE ε4 allele.
  
  
  
  In our sample, 505 (15%) had incident stroke. Among participants without stroke, the ε4 allele was associated with increased cognitive decline compared to noncarriers (0.080 vs. 0.036 units/year; P<0.0001). Among participants without the ε4 allele, cognitive decline increased significantly after stroke compared to before stroke (0.115 vs. 0.039 units/year; P<0.0001). Interestingly, cognitive decline before and after stroke was not significantly different among those with the ε4 allele (0.091 vs. 0.102 units/year; P=0.32). Poor cognitive function was associated with higher risk of stroke (hazard ratio=1.41, 95% confidence interval, 1.25-1.58), but the APOE ε4 allele was not (P=0.66). The APOE ε4 allele, cognitive function, and incident stroke were associated with mortality.
  
  
  
  The association of stroke with cognitive decline appears to differ by the presence of the APOE ε4 allele, but no such interaction was observed for mortality.
authors.affiliation: Departments of *Internal Medicine, Rush Institute for Healthy Aging ‡Neurological Sciences §Behavioral Sciences †Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago IL ∥Department of Medicine, University of Minnesota, Minneapolis, MN.
authors.forename: Kumar B
authors.initials: KB
authors.lastname: Rajan
authors.forename: Neelum T
authors.initials: NT
authors.lastname: Aggarwal
authors.forename: Julie A
authors.initials: JA
authors.lastname: Schneider
authors.forename: Robert S
authors.initials: RS
authors.lastname: Wilson
authors.forename: Susan A
authors.initials: SA
authors.lastname: Everson-Rose
authors.forename: Denis A
authors.initials: DA
authors.lastname: Evans
mesh_terms: D001741:Black or African American / Q000706:statistics & numerical data; D000368:Aged; D000483:Alleles; D053327:Apolipoprotein E4 / Q000235:genetics*; D060825:Cognitive Dysfunction / Q000208:ethnology / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008297:Male; D009026:Mortality / Q000208:ethnology*; D011446:Prospective Studies; D012307:Risk Factors; D020521:Stroke / Q000150:complications* / Q000208:ethnology; D011795:Surveys and Questionnaires; D044465:White People / Q000706:statistics & numerical data
chemical_list: D053327:Apolipoprotein E4