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Down Syndrome

Down syndrome, also known as trisomy 21, is a genetic disorder caused by the presence of all or part of a third copy of chromosome 21. It is typically associated with physical growth delays, characteristic facial features, and mild to moderate intellectual disability.

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(Source: Wikipedia)

About Down Syndrome

Down syndrome is a set of cognitive and physical symptoms that result from having an extra chromosome 21 or an extra piece of that chromosome. It is the most common chromosomal cause of mild to moderate intellectual disabilities. People with Down syndrome also have some distinct physical features, such as a flat-looking face, and they are at risk for a number of other health conditions.

What is Down Syndrome?

Down syndrome describes a set of cognitive and physical symptoms that result from an extra copy or part of a copy of chromosome 21.

Chromosomes carry the genes that tell the body to develop in certain ways and to perform certain functions. Most cells of the human body contain 23 pairs of chromosomes—one set of chromosomes from each parent— for a total of 46 chromosomes. People with Down syndrome have either a full or partial extra copy of chromosome 21, for a total of 47 chromosomes. (The syndrome is sometimes called 47,XX,+21 or 47,XY,+21 to indicate the extra chromosome 21.)

The extra chromosome disrupts the normal course of development and results in the physical features and intellectual and developmental disabilities associated with the syndrome.

The degree of intellectual disability in people with Down syndrome varies but is usually mild to moderate. Generally, children with Down syndrome reach key developmental milestones later than other children...Read more about Down Syndrome NIH - National Institute of Child and Human Development

What works? Research summarized

Evidence reviews

Galantime for dementia in people with Down syndrome

The drug galantamine has been reported to have benefits for people with mild to moderate Alzheimer's disease who do not have Down syndrome. However, people with DS tend to present with AD at a much younger age than the general population as well as being physically different in terms of size, metabolism and heart rate, and may therefore have different requirements. This review identified no randomised controlled trials of galantamine in people with Down syndrome. Further research is needed.

Rivastigmine for dementia in people with Down syndrome

The drug rivastigmine has been reported to have benefits for people with mild to moderate Alzheimer's disease who do not have Down syndrome. However, people with DS tend to present with AD at a much younger age than the general population as well as being physically different in terms of size, metabolism and heart rate, and may therefore have different requirements. This review identified no randomised controlled trials of rivastigmine in people with Down syndrome. Further research is needed.

Memantine for dementia in people with Down syndrome

Memantine is thought to improve cognitive function and slow the decline of AD over time.The effects of memantine on AD are reported to be beneficial for people with moderate to severe AD in the general population, However, people with DS tend to present with AD at a much younger age than the general population as well as being physically different in terms of size, metabolism and heart rate, and may therefore have different requirements. Results from the one randomised controlled trial for the treatment of dementia in DS are not yet available (expected 2009).

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Summaries for consumers

Galantime for dementia in people with Down syndrome

The drug galantamine has been reported to have benefits for people with mild to moderate Alzheimer's disease who do not have Down syndrome. However, people with DS tend to present with AD at a much younger age than the general population as well as being physically different in terms of size, metabolism and heart rate, and may therefore have different requirements. This review identified no randomised controlled trials of galantamine in people with Down syndrome. Further research is needed.

Rivastigmine for dementia in people with Down syndrome

The drug rivastigmine has been reported to have benefits for people with mild to moderate Alzheimer's disease who do not have Down syndrome. However, people with DS tend to present with AD at a much younger age than the general population as well as being physically different in terms of size, metabolism and heart rate, and may therefore have different requirements. This review identified no randomised controlled trials of rivastigmine in people with Down syndrome. Further research is needed.

Memantine for dementia in people with Down syndrome

Memantine is thought to improve cognitive function and slow the decline of AD over time.The effects of memantine on AD are reported to be beneficial for people with moderate to severe AD in the general population, However, people with DS tend to present with AD at a much younger age than the general population as well as being physically different in terms of size, metabolism and heart rate, and may therefore have different requirements. Results from the one randomised controlled trial for the treatment of dementia in DS are not yet available (expected 2009).

See all (74)

More about Down Syndrome

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Also called: Trisomy 21, Down's Syndrome, DS

Other terms to know:
Chromosomes, Congenital

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