Children and high blood pressure

High blood pressure is something which we think affects adults only but children and teenagers can also be affected.

Even infants can develop high blood pressure.

But high blood pressure is not usually diagnosed in children which are due to the fact that their blood pressure changes as they develop. What is considered ‘normal’blood pressure in a child will change once they reach their teenage years and so on.

High blood pressure is rare in young people but it can happen, often for much the same reasons as an adult.

High blood pressure in infants

If a very young child develops high blood pressure then this usually a case of an underlying medical condition, e.g. a problem with their heart.

Other triggers for high blood pressure include:

• Premature birth
• Failure to thrive (grow and develop)
• Kidney problems

These are likely to be the causes of their raised blood pressure levels.

High blood pressure in children

If your child is under 10 years old and has high blood pressure then this is likely to have been caused by one of the factors mentioned above.

But if they are aged 10 and above then they may have developed this for other reasons which include:

• Overweight/obese
• Poor diet (too much fat and salt)
• Lack of exercise

As you can see, these are the same ‘lifestyle factors’which cause high blood pressure in adults. Yes, some children can develop high blood pressure for exactly the same reasons as an adult.

High blood pressure in teenagers

If your teenager has high blood pressure then this may be caused by lifestyle factors such as those mentioned above. It is still unusual for a teenager to develop high blood pressure although this is starting to change with the rise in obesity.

Obesity levels are increasing in young people which pre-dispose them towards all types of health problems. This includes high blood pressure.

Untreated high blood pressure can lead to serious medical conditions later on in life such as heart disease, stroke and kidney failure. But it can be controlled via medication and a healthy lifestyle which means that the young person can lead a normal life.

Causes of high blood pressure in young people

Basically, high blood pressure in a young person is caused by a lifestyle factor or factors, or an underlying medical complaint.

If your child’s high blood pressure is caused by an underlying condition then it is called ‘secondary hypertension’. This type of high blood pressure is most common in young children and is caused by the following medical conditions:

• Type 1 diabetes
• Adrenal disorder
• Polycystic kidney disease
• Chronic kidney disease
• Heart condition
• Hyperthyroidism
• Renal artery stenosis ( a narrowing of the artery into the kidney)

But there is another type of high blood pressure which mainly occurs in older children and teenagers. This is not caused by a medical complaint and occurs for the following reasons:

• High salt intake
• Overweight
• Type 2 diabetes
• Diet high in saturated fats
• Lack of physical activity
• Family history of high blood pressure

Symptoms of high blood pressure in young people

Children, like adults do not experience any symptoms of high blood pressure but some may display the following:

• Headaches
• Poor concentration
• Chest pain
• Excessive tiredness
• Breathlessness
• Blurred vision

Severe cases of high blood pressure can cause nosebleeds, heart palpitations, dizziness and nausea.

If your child shows any of these symptoms then seek medical advice as soon as possible.

It is a good idea to have your child’s blood pressure checked on a regular basis especially if they have an underlying condition or are overweight or obese.

Blood pressure is measured using two numbers -an upper number or ‘systolic pressure’and a lower number or ‘diastolic’. These are discussed in more detail in our blood pressure readings section.

But normal blood pressure readings in children and teenagers vary according to age, sex and height. In this sense they differ from the readings used for adults.

Blood pressure readings and young people

Blood pressure readings for both children and teenagers are based upon a measurement called ‘percentile’. This is very similar to the height and weight charts used for children.

For example, if your child has a blood pressure reading which is in the 89^th percentile or lower then it means that his/her blood pressure is normal. It also means that 89% of children have the same or lower blood pressure than your child.

If your child has a blood pressure reading which is in the 95^th percentile then this means that he/she has high blood pressure.

If this is above the 99^th percentile then your child has severe high blood pressure which requires urgent treatment.

Remember: these readings are based upon your child’s sex, height and age.

The percentile chart is used for children and teenagers up to the age of 18. Once a teenager reaches 18 they are classed as an adult and their blood pressure is measured in the same way as an adult.

So, if they have a blood pressure reading of 120/80 then this is normal but anything above that is considered high blood pressure.

Your GP will not confirm a diagnosis of high blood pressure from a single reading. He or she will take three readings in a designated period of time to confirm of reject this diagnosis.

Your GP may refer your child for further tests which will be the same tests that are performed on adults. These include blood tests, urine tests and an ultrasound scan of your child’s kidneys.

Treatment for high blood pressure in young people

This is the same as for an adult. Medication such as calcium channel blockers or an ACE inhibitor will be prescribed and a few lifestyle changes recommended. So, if your child is overweight and eats a high fat diet then he/she will be advised to lower his/her salt intake and switch to low fat alternatives.

This is discussed in more detail in our treating high blood pressuresection.

It is important for your child to control his/her blood pressure to prevent the risk of serious disease such as strokes, heart attacks, kidney failure etc. These do not develop overnight but over a period of years and can cause disability or even death.