While this is rare, dementia may occur in people before age 65. A person is more likely to have a rare or genetic form of dementia if they develop it at a younger age.

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Dementia is a progressive loss of cognitive function that is severe enough to impair a person’s ability to perform daily tasks.

It mainly affects adults aged 65 and older and rarely affects younger people. Globally, it affects around 119 in 100,000 people aged 30–64.

People with early onset dementia are often in their 40s and 50s. Having dementia while in this age range may pose unique and significant challenges in their finances, family, and career.

This article discusses young onset dementia and how it affects younger people. We also explore possible causes, related conditions, diagnosis, and treatment.

Dementia in younger people, or young onset dementia (YOD), is a type of dementia affecting people younger than 65. Experts also call it early onset dementia or working-age dementia.

According to the Alzheimer’s Association, of the 5.8 million Americans with Alzheimer’s dementia, approximately 200,000 people have young onset Alzheimer’s.

Further research suggests that the age-standardized prevalence of YOD is 119 per 100,000 in people aged 30–64.

Learn more about dementia here.

The impact of the disease on the lives of younger people and their families is significantly different than it is for older people.

In some cases, dementia symptoms may appear in children and babies and progress quickly, while in other cases, symptoms may not start until the teenage years.

Dementia in young people can also be more difficult to recognize.

The following factors may contribute to delays in diagnosis:

  • being younger at the age of onset
  • having an uncommon type of dementia
  • consulting an increased number of services

Younger people also tend to have longer hospital stays due to difficulties finding age-appropriate services.

The course and characteristics of dementia in the young also differ from those in older people. The condition affects different brain regions and does not tend to affect memory. This may explain why younger people have more awareness of their disease. This is also why they are more prone to developing depressive symptoms.

Parents or caregivers can discuss specific features of YOD with a doctor.


Other initial symptoms of YOD include:

Children and younger people with dementia most likely have an inherited form of dementia or a rarer type of dementia.

Neuronal ceroid lipofuscinoses and Batten disease are rare, inherited lysosomal storage disorders. They are the most common cause of dementia in children and young adults. A person with one of these diseases usually has symptoms during childhood and may become disabled by age 20.

Niemann-Pick type C disease is a similar condition that causes childhood dementia.

Childhood dementia may also result from progressive brain damage.

Alzheimer’s in young people

Alzheimer’s disease is the most common type of dementia in young people, but its proportion is lower than that of Alzheimer’s disease in late onset dementia.

It is common for young people to have an atypical form of Alzheimer’s disease, such as:

  • posterior cortical atrophy
  • logopenic aphasia
  • behavioral/dysexecutive AD

Early onset Alzheimer’s disease is mostly genetic. Most cases of Alzheimer’s disease in people younger than 45 are due to autosomal dominant familial Alzheimer’s disease.

Research associates early onset Alzheimer’s disease that runs in families with three single-gene mutations:

  • presenilin 2 (PSEN2)
  • presenilin 1 (PSEN1)
  • amyloid precursor protein (APP)

These mutations play a role in the breakdown of APP, leading to the formation of amyloid plaques in the brain. Because the mutations are autosomal dominant, children of adults with the mutation have a 50% risk.

Having Down syndrome also increases a person’s risk of developing early onset Alzheimer’s disease.

Additionally, Black people and those of minority ethnic groups are at risk of the disease.

Aside from Alzheimer’s disease, common causes of YOD include:

Huntington’s disease

The onset of Huntington’s disease generally begins in midlife. The condition causes a progressive decline in cognition and behavior.

Depression, aggression, and other behavioral symptoms may precede motor symptoms such as chorea.


The clinical presentation of FTD is subtle and variable. A person may present with the following:

  • behavior disturbances
  • personality changes
  • loss of motivation and empathy

They may lose judgment and planning skills. As the disease advances, other symptoms, such as impulsivity and loss of social skills, may appear.

Vascular dementia

Vascular dementia occurs as a result of blood supply problems to the brain. Symptoms vary from person to person.

Memory loss is not very common. Common symptoms include slower thought processes and problems with:

  • planning
  • problem-solving
  • concentration

Secondary dementia

Secondary dementias account for 5–10% of YOD cases. These relate to the following types of disorders:

  • metabolic
  • infectious
  • autoimmune
  • neoplastic

Some examples include:

Approximately 10% of YOD cases are due to chronic alcohol misuse.

Accurate diagnosis can affect a person’s outlook since some of these conditions may be treatable.

Diagnosing YOD may involve:

  • obtaining a comprehensive history, including a person’s symptoms and how these impact their work and daily life
  • learning a person’s psychiatric, medical, and family history
  • physical and neurological exams
  • brain scans
  • lab tests
  • genetic testing
  • imaging tests such as electroencephalogram and MRI

There is currently no cure for dementia. However, several treatments can help manage the condition.

The Food and Drug Administration (FDA) has approved several prescription drugs to help manage Alzheimer’s disease symptoms. These include:

  • donepezil, which the FDA has not approved for use in children
  • rivastigmine
  • aducanumab
  • memantine

Learn more about the medication for dementia.

Talk therapies and counseling can help people with dementia come to terms with their condition.

Several forms of community support may be available for people with YOD and their caregivers, such as:

  • financial planning
  • genetic counseling
  • counseling or therapy
  • support groups like YOD Dementia Cafes and Young Onset Dementia Support Group on Facebook
  • community care programs

While many services are available to support people with dementia in general, not all services meet the needs of younger people.

A person may look for an Alzheimer’s association in their country to find support and services for their condition.

They may also benefit from the National Institute of Aging’s resource list for people with early onset Alzheimer’s disease. The list includes resources on:

  • living with the condition
  • caregiving
  • legal and financial planning

ALZConnected is a free online community from the Alzheimer’s Association for everyone with Alzheimer’s disease and other types of dementia, as well as their family members and caregivers.

A person with the condition has an average life expectancy of 4–8 years after diagnosis.

Meanwhile, a 2019 study found that the mean survival was 209 months (17.4 years) after symptom onset and 120 months (10 years) after diagnosis.

The study also noted a link between younger age at symptom onset or diagnosis and longer survival time.

In YOD, symptoms of dementia are present in people younger than 65.

A person may experience behavioral and cognitive issues. The condition typically does not affect memory in the same way in younger people as in older people, so younger people are much more aware of their condition. This could mean that people may develop depression and anxiety.

Getting an accurate diagnosis early and receiving appropriate support can significantly reduce the distress and confusion that a person and their family may experience.

A person who is concerned may make an appointment with a doctor. The doctor can help ease their worry, provide answers, and help them seek the appropriate support.