World Down Syndrome Day

Down’s Syndrome and Dementia

World Down Syndrome Day is a global awareness day advocating for the rights, inclusion and wellbeing of people with Down’s syndrome. Due to the unique makeup of chromosomes for a person living with this genetic condition, they are at more risk of developing dementia.

More than 60% of people living with Down’s syndrome will develop Alzheimer’s before the age of 60.  As with all adults the risk of Alzheimer’s increases with age and although the increased life expectancy of people living with Down’s syndrome should be celebrated, their risk of Alzheimer’s will also increase.

World Down Syndrome day is held on the 21st day of the 3rd month to highlight the triplication of the 21st chromosome which causes Down’s syndrome.

The Science

Our genetic information that defines us is divided into genes, which are stored in 23 pairs of genetic units called chromosomes.  Chromosomes generally follow the same pattern of information although there are subtle changes in different genes which make us all different to one another.

In Down’s syndrome, chromosome 21 is triplicated and therefore individuals can receive 3 times the amount of the 400 genes which make up this chromosome.

Genes tell the body how to build proteins, which are key molecules affecting all the body’s structures and functions.  One of the genes in chromosome 21, codes for Amyloid Precursor Protein (APP) which produces the protein amyloid and build-up of this protein on the brain is a key indicator of Alzheimer’s.  Due to the increased APP, people with Down’s syndrome can develop an excess of amyloid on the brain, hence why they are more at risk of developing Alzheimer’s.

Scientists have also found several genes in chromosome 21 that speed up the ageing process, which also contributes to the increased risk of Alzheimer’s.


Changes in overall function, personality and behaviour might be more prevalent early signs of Alzheimer’s for a person with Down’s syndrome, rather than memory loss.  Other indicators to look out for might be:

  • Reduced sociability and decreased enthusiasm
  • Reduced attention span
  • Sadness, fear or anxiety
  • Irritability, uncooperativeness or aggression
  • Sleep disturbances
  • Seizures beginning in adulthood
  • Changes in coordination or walking
  • Increased noisiness or excitability


It may be difficult to diagnose Alzheimer’s for a person with Down’s syndrome; unless changes have been identified by someone who has known the person for a long time, a change will likely be put down to their learning difficulty.

Baseline assessments can be used to record information such as:

  • Basic self-care skills,
  • Personal achievements
  • Academic/employment milestones
  • Talents, skills and hobbies

This information can help to compare changes as an individual gets older and can identify if someone was able to complete a specific activity in the past, but no longer able to. Ongoing evaluation of behavioural and social function is essential for a person with Down’s syndrome and the individual, family members and people close to them will be the best source of information for this.

Collating enough information about the person will allow health professionals to rule out any other physical or mental problems that might be presenting itself with the same or similar symptoms to Alzheimer’s, such as:

  • Thyroid problems
  • Depression
  • Urinary infection
  • Sleep apnoea
  • Medication side effects
  • Life changes
  • Changes in sensory impairments


If you recognise that you or someone close to you might be presenting symptoms similar to Alzheimer’s the first thing you should do is consult your GP for an assessment.  They will be able to rule out any conditions where symptoms may present as Alzheimer’s but are not.  The process of getting a diagnosis may be frightening or overwhelming and there are some people who put off having an assessment as they fear the results, however for a lot of people the diagnosis can give them a sense of relief as they have an explanation for why not only their behaviour or memory is changing but also the way they feel.

If you would like to find out more information or seek support, please get in touch with our Dementia Support Team on 01474 533990.

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