Hypertension in adolescents
Synonyms and keywords:

# Overview
Hypertension is one of the major risk factor for cardiovascular diseases. It is often associated with adverse cardiac and vascular outcomes. Hypertension in the pediatric age group often leads to the development of cardiovascular compromises for the patient, such as atherosclerotic plaques development, and renal function loss in the adulthood. To make matters worse, pediatric hypertension is greatly underdiagnosed due to the difficulty in measuring children's blood pressure, and the need to refer to detailed tables of normative values. Thus, cautious monitoring, early diagnosis, and treatment of hypertension in children is critical to prevent disease progression.

# Classification
Pediatric hypertension may be classified according to the AAP (American Academic of Pediatrics):

# Pathophysiology
- The pathophysiology of hypertension can be either primary, which is multifactorial, or secondary, in which hypertension develops as a consequence of other diseases.
- Essential hypertension can be triggered by multiple factors such as: obesity, insulin resistance, activation of sympathetic nervous system, changes in sodium homeostasis, renin-angiotensin-aldosterone system changes, disorders in the vascular smooth muscle structure or function, elevated uric acid levels, fetal programming and genetic factors.

# Causes
Based on etiology, hypertension in children can be classified into 2 groups:
- 1. Primary hypertension - No specific cause known
- 2. Secondary hypertension - Common causes include:
- Renal diseases
- Renal artery stenosis
- Obstructive sleep apnea
- Related to drugs - glucocorticoids, CNS stimulants
- Congenital adrenal hyperplasia
- Pheochromocytoma
- Hyperthyroidism
- Coarctation of the aorta

## Common causes of pediatric hypertension by pediatric age group
These conditions are displayed in order of prevalence
One to six years:
- Renal parenchymal disease; renal vascular disease; endocrine causes; coarctation of the aorta; essential hypertension
Six to twelve years:
- Renal parenchymal disease; essential hypertension; renal vascular disease; endocrine causes; coarctation of the aorta; iatrogenic illness
Twelve to eighteen years
- Essential hypertension; iatrogenic illness; renal parenchymal disease; renal vascular disease; endocrine causes; coarctation of the aorta

# Differentiating Hypertension in Adolescents From Other Diseases
Hypertension in adolescents may be a symptom of other underlying and undiagnosed conditions. Thus, these patients require a detailed medical assessment. Secondary causes were discussed above and include: renal diseases, drugs, adrenal diseases and hyperthyroidism.

# Epidemiology and Demographics
- According to the WHO, an estimated 1.13 billion people worldwide have hypertension.
- Hypertension commonly affects individuals older than 65 years of age, especially living in low or middle-income countries.
- In a study from the University of Texas' McGovern Medical School, the prevalence of pediatric elevated hypertension from 10 to 17 years of age was 16.3%, stage 1 hypertension was 10.6% and stage 2 hypertension 2.4%.
- Higher prevalence was noted in patients who were classified as obese or overweight.
- Prevalence of childhood hypertension has increased from 1994 to 2018.
- A systematic review estimated that in 2015, the prevalence of childhood hypertension was 4.32% among children aged 6 years. Patients aged 19 years had a prevalence of 3.28%. The peak of prevalence in hypertension occurred at age 14 years.

# Risk Factors
- The most common risk factor in the development of hypertension in adolescents is obesity.
- Non-modifiable risk factors include obstructive sleep apnea, diabetes, low birth weight, gender, race, genetic inheritance, socioeconomic status, premature birth, use of umbilical artery catheters and family history of cardiovascular disease.
- Modifiable risk factors include: decongestants, use of nose or eye drops, oral contraceptives, antidepressants, bronchodilators, salt intake, dietary habits, excess adiposity, physical level activity, secondhand smoke, poor sleep quality, short sleep duration.

# Screening
- According to the U.S. Preventive Services Task Force (USPSTF), screening for hypertension in asymptomatic children and adolescents is not recommended.
- According to the 2017 American Academy of Pediatrics guidelines, screening for hypertension in asymptomatic children and adolescents is recommended annually beginning at three years of age.
- According to the 2016 European Society of Hypertension guidelines, screening for hypertension in asymptomatic children and adolescents is recommended every two years beginning at three years of age.

# Natural History, Complications, and Prognosis
- If left untreated, children with hypertension may progress to develop atherosclerotic heart disease in adulthood. They have also increased risk of cardiovascular disease and mortality as well as left ventricular hypertrophy.
- Renal complications such as chronic kidney disease may develop.
- Ophthalmologic compromise is also a possible with hypertensive retinopathy being a potential complication.
- Children and adolescents with severe hypertension are at risk of developing hypertensive encephalopathy, seizures, cerebrovascular accidents, and congestive heart failure.

# Diagnosis

## Diagnostic Study of Choice
- The diagnostic study of choice for diagnosing hypertension in adolescents is the attainment of accurate blood pressure measurement in children and adolescents.
- It can be challenging due to the variance of the measurements with different cuff sizes, anxiety, patient positioning, caffeine intake, and activity levels.
- To choose an adequate cuff size, one must pick an inflatable bladder that is at least 40% of the arm circumference and a bladder length that is 80% to 100% of the arm circumference.

## History and Symptoms
- The majority of children with hypertension are asymptomatic.
- Common symptoms of hypertensive emergencies include headache, altered sensorium, seizures, vomiting, focal neurologic complaints and visual disturbances.

## Physical Examination
- Common physical examination findings of hypertension include retinal vascular changes on fundoscopy, cardiac heave, and laterally displaced point of maximal impulse (PMI) due to left ventricular hypertrophy (LVH). 

## Laboratory Findings
- There are no diagnostic laboratory findings associated with hypertension.
- To evaluate for end-organ damage, hypertension causes or hypertension-associated conditions that may increase the cardiovascular risk the following exams may be useful:
Lipid profile
Complete blood count
Fasting glucose or A1C level
ALT and AST
Drug screening
Measurement of serum blood urea nitrogen (BUN)
Plasma renin
Aldosterone activity
Creatinine
Electrolytes
Urinalysis
- Lipid profile
- Complete blood count
- Fasting glucose or A1C level
- ALT and AST
- Drug screening
- Measurement of serum blood urea nitrogen (BUN)
- Plasma renin
- Aldosterone activity
- Creatinine
- Electrolytes
- Urinalysis

## Electrocardiogram
- An ECG is not helpful in the diagnosis of hypertension.
- Findings on an ECG suggestive of hypertension include left ventricular hypertrophy, ST depression and T wave inversion.

## X-ray
- A chest X-ray is not helpful in the diagnosis of hypertension.
- There are findings on an x-ray suggestive of hypertension-associated complications, which include increased cardiothoracic ratio, secondary to left ventricular hypertrophy.

## Echocardiography or Ultrasound
- There are no echocardiography/ultrasound findings diagnostic of hypertension.
- However, an echocardiography/ultrasound may be helpful in the diagnosis of complications of hypertension, which include left ventricular hypertrophy and renovascular disease.

## CT scan
- There are no CT scan findings diagnostic of hypertension.
- It can diagnose some causes of hypertension such as coarctation of aorta or adrenal disease.

## MRI
- There are no MRI scan findings diagnostic of hypertension.
- It can diagnose some causes of hypertension such as coarctation of aorta or adrenal disease.

## Other Imaging Findings
- There are no other imaging findings associated with hypertension.

## Other Diagnostic Studies
- There are no other diagnostic studies associated with hypertension.

# Treatment
The AAP guideline recommends keeping systolic and diastolic pressure under 90th percentile or <130/80 mmHg in patients aged 13 or older to prevent any cardiovascular events.

## Medical Therapy

### Lifestyle modifications
- All children and adolescents with hypertension should change their lifestyle for the better.
- Such changes include: weight reduction if obese or overweight, regular physical activity, healthy diet (DASH diet), avoidance of substance use, stress reduction, family-based interventions (involving the whole family on such lifestyle changes can dramatically increase therapeutic adherence).

### Pharmacological treatment
- The mainstay of treatment for hypertension in adolescents is pharmacotherapy. Pharmacological therapy is reserved for those patient who have symptomatic or persistent hypertension despite lifestyle modification, stage 2 hypertension without modifiable factors, or hypertension secondary to chronic kidney disease or diabetes.
- First line medication generally include angiotensin converting enzyme inhibitors (ACEIs), angiotensinogen receptor blockers (ARBs), long acting calcium channel blockers (CCBs) and thiazide diuretics.
- Beta-blockers are not considered first line agents.
- Black patients may benefit from medications other than angiotensin converting enzyme inhibitors.
- Calcium channel blockers and hydrochlorothiazide are appropriate choices for female adolescents at risk for pregnancy.
- Start at the lowest dose and titrate every 2-4 weeks until blood pressure goal is reached.

# Surgery
Surgery is not the first-line treatment option for children with hypertension. Surgery is usually reserved for children with select adrenal disease or coarctation of aorta.

# Primary prevention
Effective measures for the primary prevention of primary hypertension in children include low sodium intake, adhering to the DASH diet, maintaining appropriate body weight, and regular physical activities.

# Secondary prevention
There are no established measures for the secondary prevention of hypertension in children.