Vascular risk factors can play an important role in determining the onset of non-genetic Alzheimer's disease (AD). Most cases of AD are sporadic and late-onset, and a complex interaction between genetic predisposition and vascular risk factors has been proposed. Vascular risk factors for AD include stroke, hypertension, diabetes, homocysteine, smoking, hypercholesterolemia, heart failure and atrial fibrillation; it is possible that these can trigger cerebrovascular dysfunction and AD pathology. Explanations for these associations include the coincidence of common disorders in the elderly where vascular and cerebrovascular disease can precipitate AD, implying that the onset of dementia disease is determined by a synergistic combination of risk factors. In this paper we review the role of cardiovascular risk factors in the pathogenesis of AD and discuss the associated brain mechanisms that can underlie the onset of AD. Cardiovascular diseases are a promising avenue of AD research because they are potentially modifiable in early adult life and provide a new perspective for the prevention of dementia.