title: Self-reported head injury and risk of late-life impairment and AD pathology in an AD center cohort.
abstract: OBJECTIVE
  To evaluate the relationship between self-reported head injury and cognitive impairment, dementia, mortality, and Alzheimer's disease (AD)-type pathological changes.
  
  
  METHODS
  Clinical and neuropathological data from participants enrolled in a longitudinal study of aging and cognition (n = 649) were analyzed to assess the chronic effects of self-reported head injury.
  
  
  RESULTS
  The effect of self-reported head injury on the clinical state depended on the age at assessment: for a 1-year increase in age, the OR for the transition to clinical mild cognitive impairment (MCI) at the next visit for participants with a history of head injury was 1.21 and 1.34 for the transition from MCI to dementia. Without respect to age, head injury increased the odds of mortality (OR = 1.54). Moreover, it increased the odds of a pathological diagnosis of AD for men (OR = 1.47) but not women (OR = 1.18). Men with a head injury had higher mean amyloid plaque counts in the neocortex and entorhinal cortex than men without.
  
  
  CONCLUSIONS
  Self-reported head injury is associated with earlier onset, increased risk of cognitive impairment and dementia, increased risk of mortality, and AD-type pathological changes.
authors.affiliation: University of Kentucky Alzheimer's Disease Center, Sanders-Brown Center on Aging, University of Kentucky, Lexington, Ky., USA.
authors.forename: Erin L
authors.initials: EL
authors.lastname: Abner
authors.forename: Peter T
authors.initials: PT
authors.lastname: Nelson
authors.forename: Frederick A
authors.initials: FA
authors.lastname: Schmitt
authors.forename: Steven R
authors.initials: SR
authors.lastname: Browning
authors.forename: David W
authors.initials: DW
authors.lastname: Fardo
authors.forename: Lijie
authors.initials: L
authors.lastname: Wan
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Jicha
authors.forename: Gregory E
authors.initials: GE
authors.lastname: Cooper
authors.forename: Charles D
authors.initials: CD
authors.lastname: Smith
authors.forename: Allison M
authors.initials: AM
authors.lastname: Caban-Holt
authors.forename: Linda J
authors.initials: LJ
authors.lastname: Van Eldik
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Kryscio
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000453:epidemiology* / Q000473:pathology; D001921:Brain / Q000473:pathology; D001924:Brain Concussion / Q000453:epidemiology / Q000473:pathology; D060825:Cognitive Dysfunction / Q000453:epidemiology* / Q000473:pathology; D015331:Cohort Studies; D006259:Craniocerebral Trauma / Q000453:epidemiology* / Q000473:pathology; D004522:Educational Status; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008390:Markov Chains; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D014474:Unconsciousness / Q000453:epidemiology / Q000473:pathology