Younger Onset Dementia

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    Dementia (also known as Neurocognitive Disorder) causes gradual deterioration in attention, decision-making, memory and learning, language, perception and /or social behaviour. It is often thought of an older person’s disease.

    However, about 5% of people who get dementia are under the age of 65; these people are referred to as having “younger onset” or “early onset” dementia. Because of the relative rarity, dementia symptoms in younger people are often missed or put down to something else like work stress, burnout, or depression.

    Furthermore, the proportion of younger people with the frontotemporal type of dementia is much greater than it is in older people with dementia. This type of dementia is often mistaken for psychiatric illness and another reason for the diagnosis to be delayed.


    The diagnosis is made the same way it is for older people with signs of dementia. The most important part is taking a history of symptoms from the patient and another person, usually a family member. This will include information about how and when changes occurred and their progression, any mental or emotional symptoms, other illnesses, usual functioning, life stresses and family history.

    The diagnosing doctor will:

    • take a thorough medical history from both the patient and someone who knows them,
    • perform an examination,
    • order blood and urine tests,
    • perform cognitive tests such as the Montreal Cognitive Assessment (MoCA),

    In addition to this it is standard procedure for a CT scan, MRI or other special scan to be ordered for people with younger onset dementia. It is likely that the GP will refer a younger person for specialist assessment. This might be to a neurologist, psychiatrist, psychologist for more in-depth testing or a Memory Clinic if there is one available. If there is a strong family history a geneticist might be involved.

    Sometimes it can be difficult to make the diagnosis, for example if the person also has depression, the doctor may try antidepressant treatment first to see if it makes a difference to cognition and function.

    What are the causes?

    Dementia of any type can begin at a younger age. However, frontotemporal dementia is a common cause of younger onset dementia.

    Who gets it?

    Some people have a family history of younger onset dementia. There are rare familial forms of Alzheimer’s or frontotemporal dementia that can afflict people in their 40s or 50s. Huntington’s chorea, a genetic condition, often leads to younger onset dementia.

    People with a history of head injury or Down syndrome are also more prone to younger onset dementia. However, even people with none of these risk factors can still develop dementia before the age of 65.

    What are the specific needs of younger people with dementia?

    People who develop dementia early in life are often still working and may be supporting the household, including children at home or through tertiary education. They are likely to be physically strong and socially active and have greater responsibility for others than older people.


    The person with dementia and their supporter lose a shared future that might have included travel and new activities later in life. There will be an unplanned loss of income as one or both of a couple must retire. With loss of employment comes loss of purpose, self-esteem, social contact, and structure to the day. The person may lose their role in the family, perhaps as carer for the younger or older generation. There are sometimes struggles with insurance companies who do not accept that a young person can have dementia.


    Care partners of people with dementia will have to take on additional tasks that their partner once performed. This might be managing the finances, raising children, or helping older parents. As the dementia progresses spouses will be required to take on aspects of caregiving that make them feel more like a parent than an equal partner. This relationship change often impacts on a couple’s sexual life.

    There are also likely to be changes in the person’s social life. People in the younger age groups might find it hard to accept or understand what is happening, or are unable to tolerate changed behaviour, so that the person with dementia is increasingly excluded from their social life and friends fade away.


    Children react differently depending on their personalities and age. Teenagers are already having to cope with a challenging life-stage so changes in the family and an unwell family member may cause embarrassment, resentment or withdrawal. They may not want to worry the cognitively intact parent with their feelings, but they need a chance to unburden about the situation. It could be important to inform the school about what is happening at home and to support the young person to find a suitable relative or counsellor to talk to.


    There are no particular residential services for people with younger onset dementia making it difficult because they are living with others who are 20 to 30 years older. Because younger people are physically stronger, this can also make managing behavioural issues more of a challenge. Finally, there are differences in funding services for people who are under or over 65 but your Dementia Advisor can help you through the bureaucracy.

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