Alzheimer's Disease: An Overview

Types of Alzheimer's Disease

Types of Alzheimer's Disease

You may be surprised to learn that there is more than one type of Alzheimer's disease. In fact, there are two types of Alzheimer's: early-onset (also called familial Alzheimer's disease) and late-onset Alzheimer's disease.

Early-Onset or Familial Alzheimer's Disease

Early-onset Alzheimer's disease, is a rare form of the disease that occurs before age 65.^[2][4] This form represents only five to ten percent of Alzheimer's disease cases. Early-onset Alzheimer's disease can occur as early as ages 30 to 40, but that is extremely uncommon. It is more common for early-onset Alzheimer's disease to happen around age 50. It is not clear whether the symptoms advance more rapidly in early-onset disease than in late-onset Alzheimer's disease.

Early-onset Alzheimer's disease often runs in families. Many people who have early-onset Alzheimer's disease have one or more of three genes linked to Alzheimer's disease. If someone has one of these genes, it is very likely that he or she will develop Alzheimer's disease before 65.

Because early-onset occurs prior to retirement age, it can impact family finances.^[2] At work, difficulties may not be recognized as Alzheimer's disease and may be mistaken for lack of motivation or even a psychiatric problem. Early-onset disease can result in job loss.

Late-Onset Alzheimer's Disease

Late-onset Alzheimer's disease Alzheimer's disease is the most common form of Alzheimer's disease.^[4] It occurs among persons 65 and older.^[4][5] Researchers have not been able to isolate unique genes contributing to late-onset disease, and it does not appear to run in families.

This Elder Health Guide was published on August 1, 2009.