Chronically elevated blood pressure is a world-wide issue and health concern. This disease is becoming ever more prevalent in children and adolescents. Pediatric hypertension is a growing health concern along with the epidemic of sedentary activity and pediatric obesity.
How common is this issue?
The prevalence of high blood pressure and chronic hypertension in the pediatric population is around six percent. This percentage precipitously elevates to 30 percent when we look at adolescents who are also obese.1
Hypertension in pediatrics leads to an increased risk of cardiovascular disease as adults. Primary hypertension in children is also associated with other risk factors for cardiovascular disease, including insulin resistance and hyperlipidemia.
Children will also be affected by organ damage from chronic hypertension. These include but are not limited to left ventricular hypertrophy and deleterious vascular changes.
Even though we are well aware of these chronic effects of long-term elevated blood pressure in children, the diagnosis is often overlooked by healthcare providers. One study has shown that only 26 percent of children with routinely elevated blood pressure consistent with hypertension have a diagnosis of hypertension in their medical record.1
However, in 2017 the American Academy of Pediatrics updated their practice guidelines on the screening and management of high blood pressure in children. Due to this, a study in 2018 has shown that there has been a significant increase in hypertension diagnoses.1
So, what is considered hypertension in children?
Normal or elevated blood pressure values for children who are one to twelve years of age should be based upon the normative distribution in a healthy child of normal weight and be based upon the age, height, and sex of the patient.
The AAP provides screening boundaries and percentile-based diagnostic tables for pediatric elevated blood pressure or hypertension, as below.
Absolute blood pressure readings are used starting at age 13 years. For these patients, elevated blood pressure is considered to be 120 to 129 mmHg systolic and less than 80 mmHg diastolic. Hypertension is diagnosed when the blood pressure is 130/80 mmHg or greater.
Hypertension in children, just like in adults, is further characterized into primary and secondary. Secondary hypertension is a case where there is an underlying, often treatable cause that is leading to the patient having hypertension; whereas primary hypertension is a diagnosis of exclusion when an underlying contributing cause is not found.
Some potential causes of secondary hypertension in the pediatric population include hyperthyroidism, Cushing syndrome, obstructive sleep apnea, coarctation of the aorta, drug-induced, rheumatologic conditions, congenital adrenal hyperplasia, hyperaldosteronism, renal parenchymal disease, pheochromocytoma, and renal artery stenosis.
Although secondary hypertension was previously more common than primary hypertension in the pediatric population, now primary hypertension accounts for the majority of childhood hypertension cases.
Risk Factors and Diagnosis of Pediatric Hypertension
There are a handful of other chronic conditions and characteristics that can increase a child risk of having hypertension. These may include obesity, sleep disorders (obstructive sleep apnea or snoring), and chronic kidney disease. A patient’s race and ethnicity can be linked to a higher risk of having hypertension, where it is known that Hispanic and African American children are at higher risk.1
A family history of hypertension or cardiovascular disease, male sex, maternal smoking, and low birth weight are all additional risk factors. Patients who were breastfed have been found to have a reduced risk of having pediatric hypertension.
The AAP recommends routinely/annually checking children’s blood pressure starting at age 3 years. Blood pressure should be measured earlier than three years if there are risk factors for hypertension including coarctation of the aorta, diabetes mellitus, taking a medication known to increase blood pressure, prematurity, family history of congenital kidney disease, malignancy, systemic illnesses, increased intracranial pressure, and history of organ transplantation.1
One of the most important parts of making the diagnosis of hypertension, whether adult or child, is getting an accurate blood pressure measurement. This can be a challenge due to the change in blood pressure dependent upon cuff size, patients stress level, time of the day, patient position, and food, fluid, of supplement intake.
To get the most accurate measurement, the patient should be sitting in a quiet room for three to five minutes with their back supported, feet uncrossed, and flat on the floor. Next, an appropriately sized cuff should be used, with the inflatable bladder width that is at least 40 percent of the arm circumference and the bladder length that is 80 to 100 percent of the arm circumference.
Arm circumference is measured from the midway point between the acromion and the olecranon as seen below. Blood pressure should be measured with the arm supported at the level of the heart. If there is a concern for coarctation, then right arm should be used for measurement. If a blood pressure measurement is elevated, a repeat should be completed in office.
In the most recent AAP guidelines, ambulatory monitoring has been recommended to aid in clarification of the potential hypertension diagnosis in children who have elevated blood pressure readings in office. This can aid in differentiating from white coat hypertension.
Once an elevated blood pressure has been confirmed during an office visit, the next step is largely dependent on the stage and degree of elevation. This may include instituting lifestyle interventions, blood work or imaging, referral to a specialist (cardiology or nephrology), monitoring closely of blood pressures, the institution of antihypertensive medications, or referral to the emergency department in severe acute hypertensive cases.
What tests should we do?
Before making any decisions to complete any diagnostic testing or imaging, a good history and physical examination must be completed, as this might point you one direction or another regarding your clinical decision-making process.
Some initial tests that are often completed are done so to evaluate for an underlying etiology, assess for any underlying cardiovascular risk factors, and assess for target end-organ damage.
All children with hypertension should have screening blood work completed with a complete blood count, comprehensive metabolic panel, thyroid stimulating hormone, hemoglobin A1c, lipid panel, and urinalysis. If the child is obese and there are liver function test abnormalities, a RUQ ultrasonography should be considered to assess for non-alcoholic fatty liver disease.
Next is the assessment for secondary causes for the patient’s hypertension. If there are findings on clinical examination that point you towards a diagnosis, the clinician should test for this. Some of these tests may include but are not limited to an upper extremity and single leg blood pressure measurements, renal ultrasonography, drug screening (urine or serum), polysomnography, EKG, and echocardiography.
Overall, the AAP recommends that children over six years old do not require an extensive evaluation for secondary causes of hypertension, if they are obese, have a family history of hypertension, and/or have a routine history and physical examination. However, also rely on your clinical experience, decision-making, and clinical findings to guide this workup.
Treatment of Pediatric Hypertension
For children, the goal blood pressure is below the 90th percentile for height, sex, and age for the patient who is younger than 13 years. For those older than 13 years, the goal is less than 130/80 mmHg.
First and foremost, all children with hypertension should make lifestyle changes that aim to lower blood pressure and reduce the risk of cardiovascular disease. The goal is weight loss for those patients who are obese with regular physical activity. This includes 30 to 60 minutes of vigorous exercise daily at least three to five times weekly. One study revealed that sticking to this exercise regimen reduced systolic blood pressure measurements seven points after participating for three months.
Another lifestyle change is diet. The Dietary Approaches to Stop Hypertension (DASH) diet has been seen to aid in the reduction of blood pressure in adolescents. These children should strive to have a diet high in fruits, vegetables, and fiber, and a reduced amount of salt intake. Tobacco and alcohol should be strictly avoided in all children, hypertension or not.
In some instances, lifestyle changes are just not enough to control a child’s hypertension. Those who have symptomatic hypertension, stage 2 hypertension without modifiable risk factors, evidence of left ventricular hypertrophy on imaging, chronic kidney disease, diabetes, or persistent hypertension, antihypertensive medications should be instituted.
There is no agreement on which antihypertensive medication should be used first-line. ACE inhibitors, ARBs, calcium channel blockers, and thiazide diuretics have been shown to be effective and safe in children with hypertension. Beta blockers are no longer recommended as first-line therapy for hypertension in children.
Specifically, in those children with diabetes, proteinuria, or CKD, an ACEI or ARB should be started. African American children should be started on thiazide diuretics or even a calcium channel blocker due to the known fact that they may be less responsive to these ACEI or ARBs.
Children should be started on the lowest dosage of the chosen antihypertensive medication. If needed, the dose can be increased every two to four weeks until the blood pressure is at goal. If the goal is not achieved when the maximum dose of a single agent is reached, then a second medication should be added on.
Remember that certain antihypertensive medications need serum monitoring, specifically ACEI, ARBs, and diuretics with serial BMP measurements. This must occur after initiation of the drug, dose increases, and intermittently afterward to assess for potassium and creatinine changes.
I hope this article is a tool in your arsenal when it comes to identifying, diagnosing, and managing children or adolescents with hypertension in your practice. If you have any questions, reach out to us at Medgeeks! Until next time!
- Am Fam Physician. High Blood Pressure in Children and Adolescents. 2018;98(8):486-494. Copyright © 2018 American Academy of Family Physicians.
- American Academy of Pediatrics. Clinical Practice Guideline for Screening and Management of High Blood Pressure in Children and Adolescents.
- UpToDate. Evaluation of Hypertension in Children and Adolescents. Accessed: March 9, 2019.