Arterial hypertension in children

How blood pressure is evaluated in children

Classic adult norms cannot be applied to children. Blood pressure (BP) is assessed using individual percentile curves, which take into account three factors: the patient's sex, age, and height.

• Target blood pressure — below the 90th percentile.
• Stage I hypertension — values ranging from the 95th percentile up to the boundary of [99th percentile + 5 mmHg].
• Stage II hypertension (severe) — mean values strictly above [99th percentile + 5 mmHg]. If systolic and diastolic pressures fall into different stages, the diagnosis is established based on the higher value.

The diagnosis cannot be made in a single visit. The physician is required to perform three measurements at each of three visits (spaced 10–14 days apart). To confirm chronic "hypertensive disease", the patient must be over 16 years old, and the condition must persist for at least a year. Prior to age 16, this diagnosis is permissible only in the presence of documented target organ damage (heart, kidneys, eyes, or central nervous system).

Essential and symptomatic forms

Globally, the condition is divided into two forms that differ fundamentally in their etiology:

1. Primary (essential) — an independent nosological entity and a diagnosis of exclusion. The exact cause is unknown, but the disease develops due to genetic predisposition, endothelial dysfunction, and sympathetic nervous system hyperactivity.
2. Secondary (symptomatic) — the consequence of a specific pathology. The causes of this form are strictly tied to the child's age:
3. In infants (under 1 year), congenital renal malformations, renal vessel thrombosis, and aortic coarctation predominate.
4. In preschoolers (1–6 years), oncological processes (Wilms tumor, neuroblastoma) and renal parenchymal lesions may come to the forefront.
5. In school-aged children and adolescents, endocrine disorders (congenital adrenal hyperplasia, pheochromocytoma, Cushing's disease) and renovascular issues prevail.

Risk assessment and target organ damage

Based on ambulatory blood pressure monitoring (ABPM) results, labile hypertension (elevated pressure index between 25% and 50%) and stable hypertension (index of 50% or more) are distinguished.

Overall cardiovascular risk is stratified based on the degree of hypertension and additional risk factors. Risk factors include obesity, left ventricular hypertrophy (LVH), dyslipidemia, and poor family history (early myocardial infarctions/strokes in relatives). The combination of hypertension with type 2 diabetes mellitus or metabolic syndrome drastically worsens the prognosis. It is important to remember that patients with Stage II hypertension are automatically classified into the high-risk group.

Diagnostic workup

In addition to taking a medical history and performing standard blood and urine tests, it is necessary to specifically assess vascular status and rule out secondary causes.

• BP measurement in legs and arms: a crucial physical examination test. If the numbers in the arms are equal to or higher than those in the legs, this is a clear marker of vascular pathology (aortic coarctation, non-specific aortoarteritis).
• Instrumental methods: ECG and echocardiography to detect cardiac overload, renal ultrasound, and fundus examination.
• Laboratory markers: biochemical screening (electrolytes, creatinine, lipid profile), and in cases of obesity, a glucose tolerance test. Markers of the sympathoadrenal system (catecholamines, metanephrines) and the renin-angiotensin-aldosterone system (RAAS) must be investigated.

Treatment approaches

In cases of labile blood pressure elevation, therapy always begins with non-pharmacological correction: normalization of routine, reduction of mental stress, therapeutic exercise, salt restriction, and physiotherapy (electrosleep, collar-zone massage).

Transition to pharmacotherapy is indicated if lifestyle modifications fail to work for more than 6–12 months, as well as in Stage II hypertension, high risk, or secondary etiology. Principles of drug prescription in pediatrics:

• Strict monotherapy at the start (a single drug at the minimum dose).
• Priority given to prolonged-release formulations for once-daily administration.
• Course duration — at least 3 months (optimally 6–12 months).

Five drug classes are approved for treating children: ACE inhibitors, ARBs, cardioselective $\beta$-blockers, calcium channel blockers, and thiazide-like diuretics.

Class and exam questions

What else to study on this topic

• Pathogenesis of endothelial dysfunction and the role of the sympathoadrenal system in the development of primary hypertension.
• ICD-10 coding of arterial hypertension, taking into account target organ damage (categories I10–I15).
• Indications and diagnostic objectives of ambulatory blood pressure monitoring (ABPM).
• Population-based and targeted prevention strategies for juvenile arterial hypertension.

Other topics in "Chapter 6. Diseases of the Cardiovascular System"

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.