Contribution of vascular pathology to the clinical expression of dementia

Vascular lesions in the brain are common with advancing age; however, the independent and cumulative contributions of postmortem vascular lesions to antemortem cognitive status are not well established. We examined association of six vascular lesions (large infarcts, lacunar infarcts, leukoencephalopathy, microinfarcts, cribriform changes, and cerebral amyloid angiopathy) with antemortem diagnoses of dementia, Alzheimer's disease (AD), and vascular dementia (VaD) in 190 older adults from an autopsy series. We also developed a summary score based on three macroscopic vascular lesions: large infarcts (0, 1, and ≥2), lacunar infarcts (0, 1, and ≥2), and leukoencephalopathy (none, mild, and moderate-to-severe). Sixty-eight percent of cases had vascular lesions. Only leukoencephalopathy was associated with dementia (odds ratio (OR) 3.5, 95% CI 1.0-12.4), and only large infarcts were associated with VaD (OR 4.3, 95% CI 1.2-15.4). The vascular score was associated with dementia (OR 1.6, 95% CI 1.2-2.3), AD (OR 1.5, 95% CI 1.0-2.1) and VaD (OR 2.0, 95% CI 1.4-3.0). Leukoencephalopathy, large infarcts, and higher vascular burden is associated with the clinical expression of dementia and subtypes.