Is late-onset Alzheimer's disease really a disease of midlife?

INTRODUCTION: Increasing evidence suggests that Alzheimer's disease (AD) may begin decades before evidence of dementia, indicating that it may be a disorder of midlife rather than old age. METHODS: In the absence of long-term prospective studies from early adulthood specifically designed to address this question, a group of international experts examined evidence presently available from previous clinical and population studies to provide an evidence-based opinion as to whether such a change in conceptualization may be justified. RESULTS: Although still lacking confirmation from dedicated prospective biomarker studies, there is already considerable evidence to suggest both risk factor exposure and brain changes may be already present in midlife. DISCUSSION: Current evidence suggests (1) that a change in clinical approach notably involving promotion of cardiovascular health in persons with a family history of AD may considerably reduce disease risk and (2) that the development of biomarkers at this early stage will lead to the possibility of clinical trials at a much earlier stage.