The major vascular risk factors such as diabetes and impaired glycemic control, hypertension, obesity and hyper-or dyslipidemia have been associated both with Alzheimer's disease and vascular dementia. The purpose of this review is to consider how vascular risk factors impact the expression of cognitive impairment in the elderly. The review will focus on how vascular risk factors are associated with changes in brain imaging and neuropathological changes. Midlife diabetes mellitus, hypertension and obesity are the most important vascular risk factors on the basis of their prevalence and associations with late-life cognitive impairment. The basis for their relationships to changes in brain integrity could either be through microvascular brain disease, Alzheimer pathology or both. Midlife vascular risk factors represent potentially modifiable conditions that could mitigate disease in the future.