[Epidemiology of Alzheimer's disease].

Because of global ageing of the population, the occurrence of Alzheimer's disease (AD) cases is increasing dramatically and AD is becoming a major public health preoccupation. By the year 2020, the World Health Organisation predicts that there will be almost 29 millions demented people throughout the world, two third of them being AD cases. This dramatic perspective could only be modified with new curative treatments or prevention. These last years, there is increasing evidence from epidemiological studies for the role of vascular risk factors in the aetiology of AD among which hypertension, type 2 diabetes, or high cholesterol. These potentially modifiable risk factors raise hope for prevention of Alzheimer's disease.