Dementia and Down syndrome
What is dementia?
Dementia is a term that includes a range of conditions that cause symptoms associated with a decline in memory or other thinking skills. Dementia causes changes to the brain which result in a decline in memory, other types of thinking, and activities of daily living. Dementia is not a normal part of ageing.
Alzheimer’s disease is the most common form of dementia that affects people with Down syndrome. People with Down syndrome can also develop other types of dementia.
Even with a diagnosis, people with dementia can live well, enjoy meaningful relationships, and continue to take part in their family and community.
Are people with Down syndrome more likely to get dementia?
There is a link between Down syndrome and dementia. People with Down syndrome are more likely to get dementia and on average at a younger age than other people in the population. Although having Down syndrome does put a person at increased risk, this does not mean that every person with Down syndrome will develop dementia. While the chance of Alzheimer’s Disease does increase with age in adults with Down syndrome, it is uncommon in people under 40.
Why do some people with Down syndrome develop dementia?
Scientists believe this is because a gene on chromosome 21 called the amyloid precursor protein (APP) gene plays a role in the brain changes associated with Alzheimer’s disease. Genes are a code for proteins, and because most people with Down syndrome have three copies of this gene, they get more of its protein.
Is there anything that can reduce the risk of dementia?
Yes, there are ways to reduce the risk of developing dementia through healthy lifestyle choices and managing health conditions. When dementia does develop, getting a diagnosis and support can assist a person to continue to enjoy an active life. Access to the right support and information early on is key.
Family members and caregivers can provide support by:
• understanding the links between lifestyle, health and dementia
• promoting healthy active living
• advocating for appropriate services and informed care.
There are a number of lifestyle factors that can help to reduce dementia risk and maintain brain health. Read more about these in our Down syndrome and Dementia Guide.
What kind of changes should I follow up on?
In people with Down syndrome, the first signs noticed by family or carers may be changes in behaviour and personality, such as an increase in stubbornness or behaving inappropriately. Other early signs include difficulty with attention, and changes in planning, solving problems, and making judgements.
Other changes may be present such as social withdrawal, confusion, irritability, repetitive speech, or seizures for the first time in adulthood. 
What do I do if I notice changes?
Not all changes in thinking or memory are due to dementia. There are other health and mental health conditions that can also have an impact on memory, thinking and activities of daily living.
It is important to get advice from a health care professional as soon as possible to rule out other health issues that can cause memory changes. Any time that a person shows a decline in their thinking or memory, or changes to personality and behaviour, it is important to talk to their doctor about it straight away.
The first step is to talk to the treating GP.  A GP assessment can be valuable to establish a baseline and for ongoing monitoring. Ask your GP whether they use assessment forms which are specifically for people with an intellectual disability or Down syndrome.
Getting a diagnosis of dementia
Getting a diagnosis can be difficult at times as there is no simple single test for dementia and it relies on comprehensive and multiple assessments. This involves ruling out other health conditions or mental health issues which could cause changes in thinking or behaviour.
Alzheimer’s disease before the age of 40 is rare. It is important to be cautious when making a diagnosis and to investigate all other treatable factors to help prevent misdiagnosis.
It is recommended that medical professionals assess baseline function annually from the age of 40 onwards. 
You can ask the general practitioner for a referral to:
- A specialist intellectual disability health clinic (if available in your area)
- A Memory Clinic
- A Medical specialist (geriatrician, psychiatrist of old age or neurologist) with expertise in dementia assessments if there is no regional memory clinic
Your local Down syndrome association or Alzheimer’s association may also be able to help with discussing referral pathways.
Where can I find dementia information and support?
Dementia Australia provides dementia information and supports.
The Australian Down syndrome associations provide support and services to people with Down syndrome and families.
Memory Clinics (Australia Dementia Network) are specialised centres for assessing people with cognitive disorders.
- People with Down syndrome are living longer and healthier lives than ever before. But with increasing life expectancies comes an increased risk of dementia.
- There are ways to reduce the risk of developing dementia through adopting healthy lifestyles and managing health conditions.
- When dementia does develop, appropriate diagnosis and support can assist a person to continue to enjoy an active life.
- For specific advice on your circumstances, talk to your GP or health care team.
Resources and guides
Down Syndrome and Dementia: a Guide for Families
A guide for families and caregivers, from Down Syndrome Australia
Alzheimer’s Disease & Down Syndrome: A Practical Guidebook for Caregivers
A guidebook from NDSS for those caring for a person with Down syndrome diagnosed with Alzheimer’s disease.
Dementia Australia provides dementia information and support.
- Dementia Australia Help Sheets.
- Dementia Australia Library
Alzheimer’s Western Australia
The Alzheimer’s WA website has a range of resources and dementia information sheets.
Dementia Enabling Environments
The Dementia Enabling Environments website provides tips for how to improve different rooms in the house to make it better suited for people with dementia
The Dementia Friendly Home App
The Dementia Friendly Home App is a tablet app that recommends practical changes carers can make in the home to assist the person living with dementia.
Dementia Screening Questionnaires
A range of screening tools have been developed for individuals with intellectual disabilities.