This entry describes Alzheimer’s disease, a disease limited to late adulthood and old age. The entry first discusses the prevalence of the disease. It then describes its symptoms, diagnosis, and prediction of future occurrence. Key neurological features of the disease are summarized.


Alzheimer’s disease (AD) is the most common type of dementia affecting older adults. It accounts for more than two thirds of dementia diagnoses (aka major cognitive disorder in the Diagnostic and Statistical Manual of Mental Disorders-V) after age 70 and affects roughly 20% of individuals in the United States after age 75. An early-onset version typically appears when adults are in their 50s and is associated with mutations in two genes (Presenilin 1 and 2), but it accounts for only a small percentage ...

  • Loading...
locked icon

Sign in to access this content

Get a 30 day FREE TRIAL

  • Watch videos from a variety of sources bringing classroom topics to life
  • Read modern, diverse business cases
  • Explore hundreds of books and reference titles