[Risk factors for Alzheimer: towards prevention?]. / Facteurs de risque de la maladie d'Alzheimer: vers une prévention?

Recent longitudinal studies have highlighted associations between Alzheimer's disease (AD) and several factors, especially some cardiovascular risk factors, including hypertension, diabetes, diet, obesity, and elevated levels of homocysteine and lipids in the blood. The strongest associations are with hypertension and diabetes. Moderate alcohol consumption also appears to be associated with a decreased risk of incident AD. Studies of the effect of interventions to control these risk factors on the onset and course of dementia report encouraging results about antihypertensive agents and statins. Benefits from other drug therapies such as nonsteroidal antiinflammatory drugs and antioxidants remain uncertain, and initial hopes for hormonal replacement therapy for postmenopausal women have not been confirmed. Physical, cognitive and leisure activities seem to provide protection against incident AD. Cautious interpretation is necessary in view of the possible biases in these studies (confounding factors as well as survival, regression dilution, and indication biases). These epidemiologic data raise questions about the diagnostic boundaries between AD and vascular dementia. Additional studies are needed to validate these concepts and to confirm the possible benefits of preventive measures.