Vascular risk factors are normally associated with cerebrovascular disease, which may lead to vascular dementia (VaD). Several recent studies suggest that there is increased risk of developing Alzheimer disease when exposed to these same vascular risk factors. In addition to old age, hypertension, peripheral arterial disease, certain types of cardiovascular disorders, diabetes mellitus, and smoking are now considered risk factors for late-onset Alzheimer disease. In this review, we examine several vascular factors and peripheral vascular pathophysiology implicated in Alzheimer disease and suggest certain mechanisms that might promote the association of vascular factors and late-onset Alzheimer disease. We support the implication that prevention or management of peripheral vascular disease may prevent or delay the onset of Alzheimer disease or mixed dementia.