Down’s syndrome is a genetic disorder that was named after John Langdon Down, the
doctor who first recognised it as a distinct condition in 1866
Symptoms of Down's syndrome
Causes of Down's syndrome
Diagnosing Down's syndrome
Treating Down's syndrome
Complications of Down's syndrome
Down’s syndrome affects a baby's normal physical development and causes mild to moderate learning difficulties. It is a lifelong condition that develops when a baby is still in the womb (uterus).
Children who are born with Down’s syndrome also have a higher chance of developing other conditions, some of which are life-threatening. For example:
- congenital heart disease –a general term that describes a series of birth defects that affect the heart
- sight and hearing problems
- Alzheimer’s disease –a common form of dementia (a deterioration of mental abilities, such as memory and reasoning) that often affects people who are over 65 years of age
How common is Down’s syndrome
Down’s syndrome is uncommon in the UK. For example, from 2007 to 2008, 1,843 cases of Down’s syndrome were diagnosed during pregnancy, and 743 babies were born with the condition. This means that about 1 in every 1,000 live births is affected by Down’s syndrome.
Down’s syndrome affects all ethnic groups equally. Boys are slightly more likely (around 15%) to be born with Down’s syndrome than girls.
The cause or causes of Down’s syndrome are unclear, but the single biggest risk factor for the condition seems to be the age at which a woman gives birth. The older a woman is when she has a baby, the higher the risk of her baby having Down’s syndrome. The greatest risk (1 in 30) is associated with women who are 45 years of age or over.
Routine screening for Down’s syndrome is carried out during pregnancy in order to identify women who are at high risk of giving birth to a child with Down’s syndrome.
If screening proves positive (confirms that the baby has Down’s syndrome), counselling is available to provide support and information, so that the woman and her partner can make an informed decision about whether to proceed with the pregnancy.
SeeDown’s syndrome - diagnosis for more information about screening.
The Down's Syndrome Handbook: A Practical Guide for Parents and Carers
Down Syndrome (The Facts)
Don't Let It Get You Down Syndrome
The outlook for Down’s syndrome can vary widely, depending on whether a child with the condition also develops any other serious health conditions.
Children with Down’s syndrome are most vulnerable during the first year of their life. About 15% of children with Down’s syndrome will die during the first year, usually from a complication that arises from congenital heart disease.
After the first year of life, the outlook for children with Down’s syndrome improves dramatically. Due to advances in treatment, the average life expectancy for a person with Down’s syndrome is around 50, and this may well improve in the future.
Raising a child with Down’s syndrome is often a challenging experience, which can sometimes be distressing. However, many parents find it an immensely rewarding experience.
Every child’s personality is different, and it is important never to stereotype a person with Down’s syndrome. However, in general terms, people with Down’s syndrome tend to have warm, gentle and cheerful personalities, despite the day-to-day problems that they have to face.
Symptoms of Down's syndrome
The symptoms of Down’s syndrome can affect a person in many different ways. However, the most obvious symptom of the condition is its effect on a person’s physical appearance.
People with Down’s syndrome tend to have a number of typical physical features. Some people with the syndrome only have a few of these features, while others are more severely affected.
The physical features of Down’s syndrome may include:
- eyes that slant upwards
- small ears
- flat back of head
- small mouth
- protruding tongue
- flattened nose bridge
- white spots on the iris (the coloured part of the eye), known as Brushfield spots
- short fingers
- broad hands with a single crease across the palm
- loose skin on the back of the neck
- loose joints (babies in particular may seem ‘floppy’)
- poor muscle tone (hypotonia)
- low birth weight
- vertical skin folds (epicanthic folds) between the upper eyelids and inner corner of the eye
All children will Down’s syndrome will have learning difficulties, which can range from mild to moderate.
One way of measuring a person’s intelligence is to use a type of test called an intelligence quotient (IQ). An IQ test involves exercises that are designed to assess specific capabilities.
The average IQ score for the general population is 100. People with Down’s syndrome have an IQ of 25 to 80, with an average score of 50.
In particular, children with Down’s syndrome may have:
- memory problems –both short-term and long-term memory
- concentration problems –many children have low attention spans
- difficulty problem solving
- difficulty understanding the consequences of their actions
Children with Down’s syndrome have delayed physical and mental development.
Children with Down’s syndrome are usually much shorter than other children their age. Growth continues through childhood but most adults with Down’s syndrome are below average height – around 158cm (5.2ft) for men and 140cm (4.6ft) for women.
With regards to mental development, children with Down’s syndrome usually take longer to reach important developmental milestones, such as:
- learning to crawl
- learning to walk
- learning to speak
- learning to read
- learning the social skills that are used for social interaction
It is important to recognise that a child with Down’s syndrome may still be able to acquire most, if not all, of the mental and social skills that most other people develop. Their development simply occurs at a slower pace.
Causes of Down's syndrome
Down’s syndrome is a genetic condition that occurs as a result of an extra chromosome.
Chromosomes are blocks of deoxyribonucleic acid (DNA) that are found in every cell in the human body. Chromosomes contain a detailed set of genetic instructions that control a wide range of factors, including:
- how the body’s cells develop
- the colour of a baby’s eyes
- the sex od a baby
A healthy person inherits 46 chromosomes from their parents – 23 from their mother and 23 from their father.
Down’s syndrome is caused by abnormalities that affect the twenty-first chromosome, known as chromosome 21.
Chromosome 21 can be affected in three main ways, leading to the three main sub-types of Down’s syndrome. These are explained below.
- Full trisomy 21 Down’s syndromeis the most common type of Down’s syndrome, accounting for 94% of all cases. Full trisomy 21 develops because every cell in the body has an extra copy of chromosome 21 (trisomy is a Greek word that means ‘third copy’).
- Mosaicism Down’s syndromeis the least common type of Down’s syndrome, accounting for 2.5% of all cases. In cases of mosaicism Down’s syndrome, some but not all cells have an extra copy of chromosome 21. The symptoms of mosaicism Down’s syndrome tend to be milder and less wide ranging compared with the other types.
- Translocation Down’s syndrome - is caused when a piece of chromosome 21 attaches itself to another chromosome in a cell. It accounts for 3.5% of cases of Down’s syndrome. The symptoms of translocation Down’s syndrome are similar to those of full trisomy 21 Down's syndrome but, unlike this form of the condition, it is occasionally possible for a parent to pass translocation Down’s syndrome on to their child (see below).
It is thought that some people do not have symptoms of translocation Down’s syndrome but they have altered genetic material that can trigger the condition in their children. These people are known as translocation carriers.
The risk of a translocation carrier passing on the condition to their child depends on their sex (this is due to the way that chromosomes are passed down through families). That is:
- male carriers have around a 1 in 35 chance of passing on the condition
- female carriers have around a 1 in 8 chance of passing on the condition
However, it is thought that most cases of translocation Down’s syndrome are not inherited in this way.
Effects of chromosome 21
The extra copy of chromosome 21 in children with Down’s syndrome leads to many parts of their body not developing properly.
Chromosome 21 is the smallest of all the chromosomes, but it still contains more than 300 different genes (units of genetic material). It is thought that many of the genes play an important role in the development of key functions of the body, including:
- the development of the heart
- the development of the brain
- the development and regulation of the metabolism (the rate at which the body uses energy)
It is not fully understood why some babies are conceived with abnormal copies of chromosomes. However, there a number of risk factors which are thought to increase the risk of having a baby with Down’s syndrome. These are outlined below.
The maternal age (the age of a woman when she becomes pregnant) is the only clear risk factor to be identified as increasing the risk of having a baby with Down’s syndrome.
The risks of having a pregnancy that is affected by Down’s syndrome increases as a woman gets older. For example, a woman who is:
- 15-29 years of age has a risk of 1 in 1,500
- 30-34 years of age has a risk of 1 in 800
- 35-39 years of age has a risk of 1 in 385
- 40-44 years of age has a risk of 1 in 106
- 45 years of age has a risk of 1 in 30
However, approximately 80% of babies with Down's syndrome are born to mothers who are under 35 years of age. This is due to the fact that women under 35 make up the majority of the child-bearing population.
There is some evidence to suggest that ‘clustering’ of new cases of Down’s syndrome does occur. Clustering means that an above-average number of cases develop over a short to medium period of time in one specific geographical area, such as the district of a city, or in a village.
This clustering of Down’s syndrome cases could be the result of chance, but some researchers have suggested that there may be certain environmental factors that increase the risk of the condition. Such factorsinclude:
- exposure to infectious agents, such as viruses, during pregnancy
- using oral contraception
- smoking during pregnancy
- exposure to radiation
- exposure to pesticides
- living near waste-disposal facilities, such as landfill sites or waste incinerators
There is little in the way of hard evidence to support any of the suggestions listed above. However, smoking is known to increase the risk of stillbirth, miscarriage and premature birth.
Further research is required in order to confirm or disprove whether environmental factors play a role in Down’s syndrome.
Diagnosing Down's syndrome
All pregnant women, no matter what their age, should be given the choice to have screening for genetic conditions such as Down’s syndrome.
Antenatal screening is a way of assessing whether your unborn baby could develop, or has developed, an abnormality during your pregnancy.
Antenatal screening cannot diagnose conditions such as Down’s syndrome, but it can determine the likelihood of your babydeveloping the syndrome.
If the risk of Down’s syndrome (or any other condition) is shown to be high, further testing can be arranged to confirm whether or not your baby has the condition. The test that is used for Down’s syndrome is a combined blood test and an ultrasound scan, which is known as the ‘combined test’.
During a blood test, a sample of your blood will be taken and tested to check the levels of certain proteins and hormones. If your blood contains abnormal levels of these substances, you may have an increased risk of having a baby with Down’s syndrome.
You will have a number of ultrasound scans throughout your pregnancy to check the development of your baby. An ultrasound scan is a painless procedure that uses high-frequency sound waves to produce a picture of the inside of your body (in this case, your womb).
In order to screen for Down’s syndrome, you will have a special type of ultrasound scan known as nuchal translucency. This type of ultrasound works in the same way as a normal ultrasound scan, but it focuses on measuring the space between the spine and the nape (the back of the baby’s neck).
All babies tend to collect fluid behind the neck. However, babies with Down’s syndrome usually have more fluid in their neck than normal. Measuring the thickness of fluid will help to determine whether your baby is likely to have Down’s syndrome.
You should ideally have antenatal screening for Down’s syndrome by the end of your first trimester (13 weeks and six days). Most women are screened between 11 to 13 weeks. However, if necessary, it is possible to have screening up to 20 weeks into your pregnancy, although you may also need more blood tests.
If the results of your antenatal screening or ultrasound scan suggest that your baby may be at an increased risk of a particular health problem or condition, such as Down’s syndrome, you may be advised to have further tests.
There are two types of test that can help to diagnose potential health problems or conditions while your baby is still in the womb. These are:
- chorionic villus sampling (CVS)
It is important to be aware that both of these diagnostic tests can, in uncommon cases, result in complications. Your GP or midwife can discuss all of your options with you in detail.
Chorionic villus sampling (CVS)
Chorionic villus sampling (CVS) involves taking a small sample of the placenta for closer examination. The placenta is the organ in which the foetus develops and is protected and nourished.
CVS can be performed after 10 weeks of pregnancy. The sample is taken either by passing a thin needle through the wall of your abdomen (tummy), or by passing a small tube through your vagina and the neck of your womb (cervix).
The needle or tube is guided into the correct position using an ultrasound scan. After the sample has been taken, it will be sent to a laboratory for testing. The results will show whether your baby has Down’s syndrome.
Possible complications of CVS can include:
- heavy bleeding
It is estimated that approximately 1 in every 100 woman will have a miscarriage after having CVS.
Amniocentesis involves taking a small sample of amniotic fluid (the fluid that surrounds the foetus in the womb) for examination.
Amniocentesis is usually carried out after week 15 of pregnancy, and it can be carried out up until week 22. The sample of amniotic fluid is taken by passing a needle through your abdomen (tummy) and womb. The sample is drawn out through a syringe.
As with CVS, the needle is guided into the correct position using an ultrasound scan. After the sample of amniotic fluid has been taken, it will be sent to a laboratory for testing.
Possible complications of amniocentesis can include:
- injury to you or your baby
As with CVS, there is also a 1 in a 100 chance of having a miscarriage after the procedure.
Being told that your baby may have Down’s syndrome can be difficult news to deal with. You will therefore be offered counselling so that you and your partner can express your feelings and ask questions about how this diagnosis may affect you both.
A counsellor will tell you which options are available to you so that you can make an informed decision about how to proceed with the pregnancy.
Diagnosis after birth
Once your baby is born, the initial diagnosis of Down’s syndrome is usually based on your baby’s physical appearance. Your doctor will assess your baby and look for the typical physical features that are associated with the condition, such as eyes that slant upwards or a flat back of the head.
If your doctor needs to definitively diagnose Down’s syndrome, they will arrange for a blood test known as a chromosomal karyotype. A sample of your baby’s blood will be taken and sent to a laboratory so that the chromosomes in the blood can be analysed. If the blood test finds that there is an extra chromosome 21, your baby will be diagnosed with Down’s syndrome.
Treating Down's syndrome
There is no cure for Down's syndrome, but there are a number of treatments that can help someone with the condition to lead a healthy, active and more independent life.
In some cases, it may not be apparent that a baby has Down’s syndrome until after they are born. Giving birth can be exciting, scary and tiring, and finding out that your baby has Down’s syndrome can be an unexpected shock.
If you have recently found out that your child has Down’s syndrome, you may feel a range of emotions, such as fear, sadness or confusion. Some people feel numb, while others feel immediately protective towards their child.
There is no right or wrong way to react after discovering that your child has Down’s syndrome. Finding out more about the conditionwill give youa better understanding about how it may affect your child’s life, as well as your own. Many parents find it reassuring to learn more about Down’s syndrome.
If your child has Down’s syndrome, it is important to remember that you are not alone in your situation. Thousands of people in the UK have Down’s syndrome. Also, many people, such as family members, carers and friends, have experience in supporting and caring for those with the condition.
You may find it helpful to talk about your experiences with other families. They can offer you advice and talk through any fears or concerns that you may have.
If you cannot find an appropriate support group, your GP should be able to put you in touch with one. The Down Syndrome Association also provides information and support for people with Down’s syndrome, as well as their families and friends.
Early intervention programmes are specifically designed for children with disabilities and learning difficulties. They focus on providing support to babies and children with Down’s syndrome, from when they are born until they are five years old.
Early intervention programmes provide healthcare, education and treatments, such as speech therapy and physiotherapy. They also give advice and support to the family looking after the child.
Early intervention is important because the earlier a child with Down’s syndrome receives the necessary help and support, the more independent and healthy they are likely to be later in life.
Your GP can give you further information about early intervention. You can also call the Down’s Syndrome Association’s helpline for more advice about early intervention (0845 230 0372). It is open from Monday to Friday between 10am and 4pm.
There are a number of different healthcare professionals who will monitor and treat someone with Down’s syndrome. These may include the following:
A physiotherapist is a trained healthcare professional who uses physical methods, such as massage and manipulation, to promote health and wellbeing.
A child with Down’s syndrome will often have physiotherapy from a young age because it can help them to improve their range of movement. Babies with Down’s syndrome may have poor muscle tone, so a physiotherapist can help them to learn to roll over, sit up or walk.
Children with Down’s syndrome may have problems learning to speak, so a speech therapistcanhelp them to learn to communicate more effectively.
Occupational therapists give peoplepractical support so that they can live more independently. For example, due to poor muscle tone (hypotonia) many people with Down’s syndrome have problems with tasks that require a certain degree of physical co-ordination, such as feeding and dressing.
An occupational therapist can help a person with Down’s syndrome by breaking down tasks into smaller steps, then helping them to learn how to complete the task,step-by-step.
People with Down’s syndrome may find it difficult to control their weight. Rates of obesity are particularly high among adults with Down’s syndrome. An estimated half of all adults with Down’s syndrome are obese.
The reasons for this are uncertain, but a combination of factors may be responsible; for example,having an underactive metabolism, which makes it more difficult to burn off calories, and leads to a less physically active lifestyle than those without the condition.
A dietitian (an expert in food and nutrition) can help someone with Down’s syndrome to devise a dietary plan that is tailored to their needs. This willensure that they are eating a healthy, nutritious and well-balanced diet.
Your GP will help you to deal with any general health problems and some of the day-to-day management of Down’s syndrome.
People with Down’s syndrome may need help in overcoming social problems, such as finding accommodation or applying for financial benefits. A social worker will help them to do this, enabling them to live more independently.
People with Down’s syndrome sometimes have hearing problems –see Down’s syndrome - complications. An audiologist (an expert in diagnosing and treating hearing conditions) will monitor your hearing in order to detect problems as soon as possible.
Ophthalmologist and orthoptists
An ophthalmologist is a health professional who specialises in treating eye conditions. People with Down’s syndrome have an increased risk of developing eye problems, such as eye infections and cataracts.
An orthoptist often works with an ophthalmologist to treat eye conditions that involve problems with eye movement and focusing ability, such as squints (strabismus) or ‘lazy eye’ (amblyopia).
SeeDown’s syndrome - complications for more information about the treatment of eye conditions in people with Down’s syndrome.
A paediatrician is a doctor who specialises in treating children. They will often help to co-ordinate all of the different types of treatment that your child needs.
A cardiologist is someone who specialises in diagnosing and treating heart conditions. People with Down’s syndrome have an increased risk of developing heart problems, so their heart must be checked regularly.
Children and adults with Down’s syndrome need regular check-ups so that their health can be closely monitored.
As those with Down’s syndrome are more likely to develop health problems, such as cataracts and hearing problems, it is very important to carefully monitor their health so that any problems can be detected and treated as soon as possible.
Someone with Down’s syndrome will usually have their sight, hearing and thyroid function (a test to determine whether the thyroid gland is releasing the right amount of hormones into the body) regularly checked. Children with Down’s syndrome will also have their growth monitored.
With help and support, many people with Down’s syndrome can live an active and independent life.
Many children with Down’s syndrome are able to go to mainstream schools. However, if your child is severely affected by Down’s syndrome, or you feel that they would benefit more from specialist schooling, there are a number of schools and other facilities that offer schooling specifically tailored to those with special needs.
Many young adults with Down’s syndrome pursue further education. Some also gain employment, usually on a part-time basis, although this will depend on the individual. Many people with Down’s syndrome enter loving relationships, although they may need guidance and support when it comes to things such as contraception.
Women with Down’s syndrome tend to have a reduced fertility rate. This does not mean that they cannot conceive children, but it does make it more difficult. Those who decide to have children will usually need specialist guidance and support to help them cope with the physical and mental demands of a newborn baby. Most men with Down’s syndrome are infertile.
If a woman has Down’s syndrome, the chance of their child also having the condition is 35-50%. It is difficult to estimate the risk if both parents have the condition because most men are unable to have children. The risk of miscarriage and premature birth is also much greater in women who have Down’s syndrome.
Although someone with Down’s syndrome may never be able to live completely independently, many people with the condition can live on their own or with someone else. In most cases, people with Down’s syndrome move into property that is owned and staffed by a housing association. The staff provide different levels of support, depending on the individual’s particular needs.
Complications of Down's syndrome
Some people with Down’s syndrome have very few health problems as a result of their condition. However, other people can be more severely affected and will need extra medical care and attention.
People with Down’s syndrome are at an increased risk of developing a number of conditions and health problems. Some of these are outlined below.
Around 40-50% of children with Down’s syndrome have a congenital heart defect. Around 60% require treatment in hospital. A congenital defect means that you are born with it.
There are several different heart problems that can affect people with Down’s syndrome. The most common types of congenital heart disease are known as septal defects, which account for 9 out of 10 cases.
A septal defect is where a hole develops inside one of the walls that separate the four chambers of the heart. The heart has two lower chambers known as the left and right ventricles, and two upper chambers calledthe left atrium and the right atrium.
Septal defects, often referred to as ‘a hole in the heart’, can cause a build-up of blood in one or more of the heart’s chambers. This can place extra strain on the heart because it has to work harder to pump blood through the four chambers.
Less common serious types of congenital heart disease in people with Down’s syndrome include:
- tetralogy of Fallot , which accounts for 6% of cases
- patent ductus ateriosus, which accounts for around 4% of cases
Tetralogy of Fallot is a combination of four different heart defects that causes a lowering of oxygen levels in the blood. This can lead to symptoms of breathlessness.
Patent ductus ateriosus (PDA) is a duct or passage in the heart that usually closes shortly after birth. However, in cases of PDA, the duct fails to completely close, which means that oxygen-rich blood that is meant to be pumped away from the lungs leaks back through the duct and into the lungs.
This can place strain on the heart and the lungs because they have to work harder to compensate for the problems caused by the duct.
If your baby is diagnosed with Down’s syndrome, their heart will be carefully assessed so that any heart defects can be detected and treated as soon as possible. In around 30% of cases, the heart defect is serious and may require immediate surgery. In other cases, the heart can be monitored and treated at a later date, if necessary.
Minor septal defects can usually be treated with minor surgery. Larger defects will need open heart surgery to correct. Tetralogy of Fallot usually requires open heart surgery, and several operations may be needed to restore normal heart function. PDA can usually be treated with medication that encourages the duct to close.Hearing problems
Around 50% of people with Down’s syndrome have problems with their ears and hearing.
Glue ear is a condition that commonly affects people with Down’s syndrome. It is caused by a build up of fluid in the middle ear. In some cases, the fluid thickens and makes sounds appear muffled and distorted.
If your child has a hearing problem, they may find it difficult to learn and interact with other children. If your child has glue ear as a result of Down’s syndrome, they will usually be referred to an ear, nose and throat (ENT) specialist for treatment.
Around 50% of people with Down’s syndrome also have problems with their eyesight.
A squint, which is a condition where one eye turns inwards, outwards, upwards or downwards, is common in people with Down’s syndrome, but can usually be successfully treated by wearing glasses. But occasionally, surgery may be used to correct a squint.
Other eye problems can include:
- lazy eye- where one eye does not develop fully so loses some focusing ability
- short sightedness- where distant objects appear blurred
- long sightedness - where nearby objects appear blurred
- eye infections - most infections occur in either the membrane that covers the eye (conjunctivitis), the middle layer of the eye (uveitis), or the eyelids (blepharitis)
- cataracts - where the lens (the transparent layer at the front of the eye) clouds over
- nystagmus - where the eyes move uncontrollably, usually from side to side
- keratoconus - where the cornea becomes thin and bulges out
Many people with Down’s syndrome experience problems with their oral health such as:
- tooth decay- where teeth are gradually broken down by bacteria
- periodontitis - an infection of the gums and surrounding tissue and bone
People with Down’s syndrome often have poor levels of oral health because:
- they may find it difficult to brush their teeth
- they often have lower levels of saliva than most people, and saliva provides some protection against bacteria
It is recommended that all people with Down’s syndrome regularly brush their teeth with a high-fluoride toothpaste (your pharmacist can advise you about this).People with Down’s syndrome may find using an electric toothbrush easier than using a manual one. Those who have particularly severe Down’s syndrome may need to have help brushing their teeth. Thyroid problems
Around 10% of people with Down’s syndrome have problems with their thyroid gland. The thyroid gland is located in the neck and is responsible for controlling your metabolism (the rate at which your body uses up the energy). It does this by releasing thyroid hormones into the body.
Most people with Down’s syndrome have hypothyroidism, which means their thyroid gland is under-active because it does not produce enough hormones. Symptoms of an under-active thyroid gland can include:
- lethargy (lack of energy)
- weight gain
- slow physical and mental reactions
- muscle aches and weakness
- dry, flaky skin
In rarer cases, people with Down’s syndrome can also develop hyperthyroidism, which means their thyroid gland is over-active and produces too much thyroid hormone. Symptoms of hyperthyroidism can include:
- difficulty breathing
- mood swings
- difficulty sleeping
- lethargy (lack of energy)
- muscle weakness
- the need to pass stools or urine frequently
Increased susceptibility to infection
People with Down’s syndrome are 12 times more likely to develop an infection compared with the general population, particularly the lung infection pneumonia. This is because their immune system (the body’s natural defence against infection) has not developed properly.
Children with Down’s syndrome have an increased risk of developing acute leukaemia, which is a form of cancer that affects the white blood cells (the cells responsible for fighting infection and protecting against it).
Some research suggests that children with Down’s syndrome are 56 times more likely to develop acute leukaemia before the age of five, compared with children who do not have the condition.
Even though a child with Down’s syndrome has an increased risk of developing leukaemia, it does not necessarily mean that they will develop the condition. For example, only 1 in 100 children with Down’s syndrome go on to develop acute leukaemia.
Many people with Down’s syndrome have some sort of intestinal problem. Some problems are mild and are common in people with and without Down’s syndrome. For example, constipation, diarrhoea and indigestion are all common.
However, people with Down’s syndrome are more likely to have more significant intestinal problems, such as small bowel obstruction, which stops food passing from the stomach into the large bowel.
An estimated 5-15% of people with Down’s syndrome will develop coeliac disease, which is a condition where a person has an intolerance to gluten, a type of protein found in most cereals.
Conditions such as imperforate anus (where a baby is born without an anal opening), or Hirschsprung’s disease (where the large bowel is unable to push faeces towards the anus) are relatively rare, but are slightly more common in children with Down’s syndrome. For example, approximately 2% of babies with Down’s syndrome develop Hirschsprung’s disease.
Psychological and behavioural conditions
Around 1 in 5 people with Down’s syndrome will develop a psychological or behavioural condition.
Conditions that can develop in younger children include:
- attention deficit hyperactivity disorder- a behavioural condition that is characterised by a short attention span and impulsiveness
- autistic spectrum disorder- a developmental disorder than can cause problems with language, behaviour and social interaction
Conditions that can develop in teenagers and adults include:
- depression- a condition that causes persistent feelings of extreme sadness
- obsessive compulsive disorder- a health condition that is usually associated with both obsessive thoughts and compulsive behaviour
People with Down’s syndrome are more likely to develop dementia when they get older and, in particular, a type of dementia that is known as Alzheimer’s disease.
Alzheimer's disease attacks nerves, brain cells and neurotransmitters (chemicals that carry messages to and from the brain).
This can lead to a progressive loss of mental function, and causes symptoms such as:
- poor memory and forgetfulness
- mood swings
- speech problems
Compared to the rest of the population, people with Down’s syndrome tend to develop Alzheimer’s disease at an early age. Approximately 40% of 50 to 59-year-olds with Down’s syndrome develop Alzheimer’s disease. Two thirds will develop Alzheimer’s disease by the time they reach 60.
A number of medications, such as donepezil and rivastigmine, can be used to slow down the loss of mental function, but it is currently uncertain whether these medications are effective in people with Down’s syndrome. Further research is required.
Many older people who have Down’s syndrome will develop problems with eating, drinking and swallowing. The medical term for this is dysphagia.
Dysphagia can be caused by a number of factors, such as a complication of severe Alzheimer’s disease or the wasting of the muscles that are used in swallowing.
Dysphagia is a potentially serious condition because it is possible for small pieces of food or drink to fall down into the lungs and trigger a serious infection. This is known as aspiration pneumonia and can often be fatal.
Mild to moderate dysphagia can be treated by making simple dietary changes. For example, eating soft foods that are easy to swallow, such as soup or mashed potatoes. However, more severe cases may require the use of a feeding tube.
Organisations and Resources
Down's syndrome - Wikipedia - http://en.wikipedia.org/wiki/Down_syndrome
Down’s Syndrome Association -Providing information and support on ALL aspects of living with Down's syndrome to ALL who need it.
Down’s Syndrome Scotland - Work to help people with Down’s syndrome reach their full potential by providing information and support for them, their families, carers and professionals.