AD is a slowly progressing, irreversible neurodegenerative brain disease with a long preclinical phase (up to 20
years) and an average clinical duration of 8 to 10 years. The progression of AD is accompanied by changes to the
brain that serve as biomarkers of the disease.1,2
Disease progression typically spans several stages, including preclinical AD, the mild cognitive impairment (MCI) stage of AD, and the dementia stages of AD, which progress from mild to severe.1
The differences between normal aging and early-stage AD can be subtle. Individuals in the MCI stage may have difficulty learning new information or their recall may be significantly impaired.1,7
Examples of early-stage AD concerns include8: