Primary Prevention of Dementia: An Epidemiological Point of View

From an epidemiological perspective, in order to increase the level of evidence, it is necessary to refer to data from longitudinal studies to validate the temporal relationship between exposure (e.g. the behavior or modifying factor) and the disease. Findings from such studies are useful for defining risk factors and laying the groundwork for proposing interventions for prevention. This step is crucial in order to define the periods (life-course approach) and groups at risk, which will then become the targets of interventions designed to modify behaviors or lifestyle. Specifying the underlying mechanisms of these risk factors is one of the objectives of etiological epidemiology which focuses on the origin of diseases but is not essential for a more pragmatic interventional approach. These questions are essential for dementia prevention and are discussed in this paper. Furthermore, timing interventions is a major problem even if we identify primary prevention pathways in dementia. Another important concern for epidemiologists is the need to make projections to estimate the number of dementia cases in the next decades considering different intervention scenarios. These models require adequate descriptive indicators of dementia, demography and mortality and precise estimations of the impact of potential interventions in terms of delaying disease onset for instance.