Risk of incident clinical diagnosis of Alzheimer's disease-type dementia attributable to pathology-confirmed vascular disease.

INTRODUCTION: The presence of cerebrovascular pathology may increase the risk of clinical diagnosis of Alzheimer's disease (AD).

METHODS: We examined excess risk of incident clinical diagnosis of AD (probable and possible AD) posed by the presence of lacunes and large infarcts beyond AD pathology using data from the Statistical Modeling of Aging and Risk of Transition study, a consortium of longitudinal cohort studies with more than 2000 autopsies. We created six mutually exclusive pathology patterns combining three levels of AD pathology (low, moderate, or high AD pathology) and two levels of vascular pathology (without lacunes and large infarcts or with lacunes and/or large infarcts).

RESULTS: The coexistence of lacunes and large infarcts results in higher likelihood of clinical diagnosis of AD only when AD pathology burden is low.

DISCUSSION: Our results reinforce the diagnostic importance of AD pathology in clinical AD. Further harmonization of assessment approaches for vascular pathologies is required.