Commentary on “Developing a national strategy to prevent dementia: Leon Thal Symposium 2009.” Creating a national database for successful aging

The Leon Thal Symposium convened in the fall of 2009. One of the topics discussed focused closely on the development and design requirements for a National Database for Longitudinal Studies, as a ‘‘core’’ facility—a shared national resource—not only for research on the natural history of cognitive impairments, but also for studies of successful aging .A n integral component of such a database, as well as the related longitudinal studies, is the capability of the field to identify, capture, and track asymptomatic people with elevated-risk for cognitive impairments. The development of technologies to identify and differentiate people at risk from those with mild cognitive impairment as potential volunteers for longitudinal studies is an urgent need. The ‘‘definition’’ of a case or research subject is an essential ingredient for the successful execution of any clinical research; however, the challenge of defining a case for future population-based prevention studies of AD is particularly important and a problematic objective. In most memory assessment clinics (either academic or non-academic) or centers, AD patients are typically evaluated in the symptomatic stages of the disease (eg, mild cognitive impairment [MCI], mild, moderate, or severe). In these settings, the establishment of the diagnosis involves a careful clinical history, physical examination, neurological examination, biochemical screening tests, and brain imaging. The evaluation frequently includes one or more neuropsy