Vascular risk factors and Alzheimer's disease

Objective: We aim to summarise the recent and accumulating epidemiological research which suggests that cardiovascular disease and vascular risk factors play an important role as risk factors for Alzheimer's disease (AD) in later life. Method: The epidemiological literature is summarised in considering the evidence for such an association, focusing on optimally designed population-based studies. Potential mechanisms of association are considered, drawing on relevant findings from neuroscience. Results: Cardiovascular disease and vascular risk disorders appear to be important factors in the aetiology of AD. However, there is a paucity of prospective studies with an adequate duration of follow-up to investigate the apparent age- and time-dependent nature of these associations. Conclusions: Vascular disorders represent potentially preventable risk factors with an important population impact due to their high prevalence in developed countries. The concept of AD and vascular dementia as clearly distinguishable disorders clinically or aetiologically is becoming increasingly tenuous. A better understanding of the relationship between AD and vascular disorders will depend on a more flexible diagnostic and conceptual framework.