Clinical diagnosis in preclinical stage of Alzheimer's disease.

Preclinical diagnosis of Alzheimer's disease using biomarkers has become an area of great interest for both clinicians and researchers because, among other advantages, this would increase the response to new disease-modifying drugs. However, difficulties with compliance and economic costs marginalize many countries worldwide that do not have access to this new type of diagnosis. The opportunity exists to refine the conventional clinical method, without using biomarkers, to attempt an earlier diagnosis as there is information that supports the potential utility of a focused clinical interview, observation of gait and use of more demanding memory tests.