[The Need for a Trial Ready Cohort of Preclinical Alzheimer's Disease].

In order to slow the predicted increase in the number of individuals with dementia, disease-modifying drugs for Alzheimer's disease (AD) are under development. Early-stage intervention is thought to be required for AD, since this disease involves a very long pathological process that leads to dementia in the final stage, when disease-modifying drugs have little effect. To justify this early intervention, we establish the concept of preclinical AD, when AD pathology is already present prior to the onset of cognitive decline. Since individuals with preclinical AD have no symptoms, we need to establish an effective way to recruit them to clinical trials.