Preclinical Alzheimer's disease

Alzheimer's disease begins long before any symptoms become apparent. This stage is called preclinical Alzheimer's disease, and it's usually identified only in research settings. You won't notice symptoms during this stage, nor will those around you.

This stage of Alzheimer's can last for years, possibly even decades. Although you won't notice any changes, new imaging technologies can now identify deposits of a protein called amyloid-beta that is a hallmark of Alzheimer's disease. The ability to identify these early deposits may be especially important for clinical trials and in the future as new treatments are developed for Alzheimer's disease.

Additional biomarkers — measures that can indicate an increased risk of disease — have been identified for Alzheimer's disease. These biomarkers can be used to support the diagnosis of Alzheimer's disease, typically after symptoms appear.

Genetic tests also can tell you if you have a higher risk of Alzheimer's disease, particularly early-onset Alzheimer's disease. These tests aren't recommended for everyone, but you and your doctor can discuss whether genetic testing might be beneficial for you.

As with newer imaging techniques, biomarkers and genetic tests will become more important as new treatments for Alzheimer's disease are developed.