[Epidemiology of Alzheimer's disease: methodological approaches and new perspectives]. / Epidémiologie de la maladie d'Alzheimer : aspects méthodologiques et nouvelles perspectives.

Over the last 20 years, a number of epidemiological studies on Alzheimer's disease (AD) have been conducted on large cohorts providing databases for studying the disease frequency, and leading to a more global overview of AD risk factors. However, precise identification of factors which potentiate or delay the pathological process of the disease is still incomplete. One of the major problems comes from difficulties for defining the cases and obtaining good clinical diagnoses in population-based studies. Moreover, it is difficult to determine the chronology of exposure-disease relationships whatever the factors studied: vascular factors, life habits (dietary habits, physical, social or intellectual activities...). Which life-course period is important for proposing interventions to modify these factors remains a central question. The longer follow-up of large cohorts and a better knowledge of potential risk factors constitute a research priority if we want to prevent efficiently AD in the near future.

[Epidemiology of dementia]. / Epidémiologie des démences.

Dementia is a major public health problem and its burden will increase in the 30 years to come. Prevalence increases with age and incidence is slightly higher in women than men, especially after the age of 80 years. Survival after the onset of dementia is approximately 5 years. Lifestyle and health habits are a keystone for dementia: risk factors include physical, intellectual and social activity and nutritional habits. Data from well-conducted intervention studies are necessary to show whether better care for hypertension, diabetes, and dyslipidemia might decrease the incidence of dementia.