Normal and Abnormal Blood Pressure for the Teens

A blood pressure reading of 120/80 is considered normal for adults over the age of 18 years; however, for those who are under the age of 18, normal blood pressure reading is based upon a percentile rating for the teen’s height, age and gender. A blood pressure reading higher than the 90^th percentile is considered out of the normal range. 18 and 19 year olds should have a blood pressure reading of 120/80, which is also considered normal for an adult.

Blood pressure reading of a teen between the 90^th percentile and the 95^th percentile is considered prehypertension or borderline and greater than 95^th percentile is considered high. Teens that have their blood pressure in the normal range should get their blood pressure checked yearly. Those teens whose blood pressure lies above the 90^th percentile should talk to their physician about the frequency of blood pressure checkups.

A table is published by the National Heart, Lung and Blood Institute that lists normal blood pressure for teens. For instance, at the age of 13, the highest normal blood pressure reading for boys in the 95^th percentile for height is less than 126 systolic over 79 diastolic; whereas for girls of the same age in the 95^th percentile for height, it should be no higher than 124 systolic over 79 diastolic.

Understanding Percentile

To understand percentile, see this example: Suppose the blood pressure reading of 100 teenage boys of same height and age is measured and recorded. Among these the top 5% readings or the 5 highest readings will be the blood pressure values above 95^th percentile. Similarly, the top 10% or the 10 highest readings will be the readings above 90^th percentile. If this procedure is done for 1000 boys then the top 5% will be top 50 boys and top 10% will be top 100 boys.

In order to define the normal values of blood pressure for a particular gender, height and age, the blood pressure of a large amount of persons with same age, height and gender are recorded and the blood pressure reading above which the top 5% and 10% of the values are found is recorded. This is used as the criteria for diagnosis blood pressure in that group (gender, age and height).

How High Blood Pressure Is Diagnosed in Teens?

To diagnose hypertension in teenagers, blood pressure has to be measured multiple times over a period of 2-4 weeks. Hypertension is not diagnosed on the basis of a single reading unless it is accompanied by symptoms or is an extremely high reading.

Since the normal blood pressure varies with the age, gender and height in children and adolescents, the diagnosis of hypertension in teens are different with that of adults.

As per the criteria that is currently accepted (The Fourth Report on the Diagnosis, Evaluation and Treatment of High Blood Pressure in Children and Adolescent):

• Prehypertension in children refers to that average SBP (systolic blood pressure) and/or DBP (diastolic blood pressure) is equal or greater than the 90^th percentile, but less than the 95^th percentile.

• Hypertension refers to average SBP and/or DBP is higher than or equal to the 95^th percentile for age, sex and height on 3 or more occasions.

• Adolescents who have BP levels higher than or equal to 120/80 mmHg should be categorized as prehypertensive.

How to Treat High Blood Pressure in Teens

A blood pressure reading over the 90^th percentile for height, age and gender of a teenager requires treatment. A thorough evaluation is done to find out a primary cause for the high blood pressure. If it is secondary hypertension, the management is aimed at treating the primary cause. For instance, if the high blood pressure is due to pheochromocytoma, it will be removed surgically. However, if the primary cause cannot be cured, secondary hypertension is treated by using anti-hypertensive medicines.

In cases where high blood pressure has no obvious cause, medicine is not indicated to treat prehypertension unless it is associated with other conditions such as heart failure, diabetes mellitus, and kidney disease, hypertrophy of the heart (left side) or evidence of damage to organs due to hypertension. Such cases are treated with modifications in lifestyle such as dietary management, aerobic exercise, abstinence from smoking and alcohol, control of weight in overweight individuals, etc. Teens that have hypertension require anti-hypertensive medicines along with lifestyle modifications.

How to Prevent Hypertension in Teens

It is recommended to adopt a healthier lifestyle irrespective of the blood pressure reading. The most important modifications in lifestyle are:

• Adopting dietary modification (DASH-type diet)

• Restricting sedentary lifestyle and doing aerobic exercise

• Controlling weight If overweight

• Reducing intake of salt in diet

• No alcohol

• No smoking

• Taking at least 7-8 hours of sleep

What Are the Causes of Low Blood Pressure in Teens?

The various causes of low blood pressure in teens are listed below:

• Heart problems

• Hormonal disorders

• Infections

• Diarrhea

• Medicines

• Blood loss

• Condition of the nervous system

• Dehydration

• Kidney problems

• Liver problems

• Pregnancy

Majority of the teens suffer from low blood pressure due to hormonal problems, dehydration, severe weight loss and poor dietary habits, etc.

What Are the Symptoms of Low Blood Pressure in Teens?

The various symptoms of low blood pressure in teens are listed below:

• Fatigue or tiredness

• Fainting

• Nausea

• Clammy skin

• Depression

• Dizziness

• Irregular heartbeats

• Excessive thirst

• Lack of concentration

• Blurred vision

• Weakness

How to Treat and Care for Teens Suffering from Low Blood Pressure?

The usual treatment for low blood pressure is to treat the cause or the condition causing the symptoms of low blood pressure. For example, if your teen’s hypotension is due to thyroid disorder, then treating it will resolve the issue of low blood pressure as well.

Doctors prescribe treatment plans to raise and maintain the blood pressure readings at optimum levels. The following steps are included in the treatment plan:

• Increased intake of salt until the blood pressure reading returns to normal.

• Maintain adequate hydration by drinking lots of fluids in the form of water and fruit juices.

• Teenage girls should consume more iron rich foods during their menses to compensate for the blood lost during menstruation.

• A healthy and balanced diet containing fruits, vegetables, lean meat, whole grains and low-fat dairy can help maintain normal blood pressure levels.

• Some medicines may be prescribed to treat severe cases of hypotension. These help raise the volume of blood, thereby, raising the blood pressure to normal levels.