RT Journal
A1 James BD, Bennett DA, Boyle PA, Leurgans S, Schneider JA
T1 DEmentia from alzheimer disease and mixed pathologies in the oldest old
JF JAMA
JO JAMA
YR 2012
FD May 2
VO 307
IS 17
SP 1798
OP 1800
DO 10.1001/jama.2012.3556
UL http://dx.doi.org/10.1001/jama.2012.3556
AB 
To the Editor: The oldest old (≥90 years of age) are the fastest growing segment of the US population and account for half of all persons with dementia. Alzheimer disease (AD) is the most common pathology underlying dementia in the old (ages 65-89 years). Recent community-based autopsy studies1- 2 suggest the relationship between AD pathology and expression of dementia is attenuated in the oldest old.3 Studies may be complicated by the common coexistence of AD plus infarct and/or Lewy body (LB) pathology (mixed pathologies).4 Few data exist on mixed pathologies and dementia in the oldest old.5 We examined the relationship of AD and mixed pathologies to dementia in the oldest old compared with the old. We tested the hypothesis that the clinical expression of AD and mixed pathologies differs across age groups.