Early-onset dementia is when the symptoms of dementia begin before the age of 65. It is sometimes referred to as younger-onset dementia.
Early-onset dementia is much less common that the usual late-onset dementia (after the age of 65). Early-onset Alzheimer’s disease is the most common cause of early-onset dementia. When Alzheimer’s disease causes early-onset dementia rather than late-onset, a person is more likely to have a variant of Alzheimer’s disease that doesn’t affect memory as severely as typical Alzheimer’s disease. A person is also more likely to have a greater delay in diagnosis, because dementia is unexpected at younger ages and the symptoms may be overlooked or misinterpreted.
Frontotemporal degeneration is the second most common cause of early-onset dementia, and is the most common cause of dementia among people at the youngest ages before 60 years old.
There is no cure for early-onset dementia caused by a neurodegenerative disease like Alzheimer’s disease or frontotemporal degeneration. A comprehensive evaluation can clarify if the cognitive changes in a person under 65 are caused by early-onset dementia rather than just normal aging.