High Blood Pressure in Children: Causes and Treatments

Dr. Maria Kiaffas, Heart Center

High blood pressure, also known as hypertension, is considered a disease of the adults, but it can also occur in children. It is known that three-to-five percent of children and adolescents have hypertension and although its effects are not as apparent in children, it has sequelae that will appear later in life. That is why it is very important for hypertension to be identified and managed as early as possible.

The causes of high blood pressure in children vary; behavioral/environmental, genetic and physical factors can cause hypertension. Hypertension can be idiopathic or primary, meaning that it occurs with no identifiable cause, or it can be secondary, meaning that it is associated with some type of disease usually renal (from the kidneys), cardiac or endocrine.

Hypertension in children should be taken seriously since it gradually causes changes in the heart and the vessels of the body. In the majority of cases it has no symptoms and is “silent” thus it is hard to be detect. Most children with hypertension will continue to have high blood pressure as adults with an increase in heart disease and stroke.

Diagnosing Hypertension in Children

Early diagnosis is key, and as important it is to take your child for a wellness visit once a year, it is equally important to have their blood pressure checked especially when they are three years or older. Children with known history of renal or cardiac disease should have their blood pressure taken more often.

It important to have your child’s blood pressure measured properly in order to avoid falsely high blood pressure readings. To obtain a proper reading, your child needs to be calm for a few minutes before the test in done; it's also important to have a proper blood pressure cuff used. Both those facts are known to health care providers that take care of children, but are often overlooked when blood pressure is taken by providers who do not care for children.

Another factor that could impact the outcome of your child’s reading is what is called white-coat hypertension. This is when your child’s blood pressure reading becomes elevated at the doctor’s office, but is otherwise normal when they’re in another setting i.e. at school when the blood pressure is taken by the school nurse, a person familiar and less threatening to them. This high reading is related to the anxiety a child has during visit to the doctor.

If a blood pressure measurement is high, it should be measured at a later time, since it takes at least three elevated measurements before someone is suspected to have hypertension. Once the diagnosis is confirmed it is important to find the reason that causes the high blood pressure.

What Causes Hypertension

Idiopathic or Primary Hypertension

It is the most common type in which the child has high blood pressure, but there is no identifiable medical condition that it can be attributed to. A considerable number of children and adolescents have idiopathic hypertension and most of them are overweight or obese and lead a sedentary life. Modifications in lifestyle such as a healthier, more balanced diet including less processed foods and salt, as well as increase in physical activity, have been shown to decrease blood pressure and in some cases even result in its normalization.

Making these lifestyle changes is very important because adolescents who are obese and hypertensive have a higher chance of being obese and hypertensive later on in life, a fact that increases their risk for premature cardiovascular disease.

Secondary Hypertension

Secondary hypertension is the result of the presence of another disease, most commonly kidney disease, endocrine or metabolic, as well as cardiac disease or other rare systemic illnesses. Another factor frequently ignored is medication that a child is taking. Medications prescribed for ADHD, some antidepressants and amphetamines can all elevate blood pressure, so can the increased consumption of caffeinated or energy drinks. Finding the underlying cause of hypertension is very important, that is why a thorough evaluation is needed with a detailed physical examination, as well as consideration of personal, family and social history of the child. This will be the appropriate screen for excluding an underlying disease be it renal, cardiac or otherwise; it will also lead to a further targeted evaluation with additional tests, as well as to appropriate therapy if such conditions are discovered.

Treating Hypertension

Hypertension is a disease that can be managed successfully. In cases of idiopathic hypertension lifestyle modifications can be very effective. Healthy diet including a reasonable amount of salt, and well-balanced meals – plate model - containing two quarter vegetables, one quarter protein and one quarter carbohydrates. A lot of starches and sugar in the diet leads to obesity and obesity leads to high blood pressure. Weight loss and a good diet combined with increased physical activities (at least three-to-five times a week and for at least half hour at a time), and decreased screen-time will decrease high blood pressure measurements in the majority of cases.

In cases of secondary hypertension addressing the main problem that causes the high blood pressure might be effective, but in some cases additional medical treatment might be needed. Management of these patients needs to be in specialty clinics; a multi-disciplinary care team will ensure adequate management.

Overall, the best preventative medicine is having annual well-child physical exams and avoiding bad habits and factors that will make our children to become overweight or obese. Healthy habits go along with a healthy child, and a healthy child guarantees a healthy adult.

Learn more about Preventive Cardiology at Children's Mercy.

Learn more about the Hypertension Clinic at Children's Mercy.