Mixed brain pathologies account for most dementia cases in community-dwelling older persons

To examine the spectrum of neuropathology in persons from the Rush Memory and Aging Project, a longitudinal community-based clinical-pathologic cohort study.

The study includes older persons who agreed to annual clinical evaluation and brain donation. We examined the neuropathologic diagnoses, including Alzheimer disease (AD) (NIA-Reagan Criteria), cerebral infarctions, and Parkinson disease/Lewy body disease (PD/LBD), in the first 141 autopsies. We calculated the frequency of each diagnosis alone and mixed diagnoses. We used logistic regression to compare one to multiple diagnoses on the odds of dementia.