Paediatric hypertension — Frequently asked questions (FAQ)
1) What does this algorithm cover?
The algorithm provides guidance on screening and the initial assessment of blood pressure in children and adolescents, from the correct measurement technique to classification as normal blood pressure, elevated blood pressure, stage 1 hypertension or stage 2 hypertension, and the corresponding reassessment plan. It includes interpretation based on percentiles adjusted for age, sex and height, as well as the use of absolute thresholds in adolescents aged 13 years or older. It also includes severity and urgency criteria requiring immediate referral.
2) At what ages should blood pressure be measured?
Universal blood pressure measurement is recommended from the age of 3 years during routine healthcare appointments. In children younger than 3 years, blood pressure should be measured when risk factors are present, such as kidney disease or uropathy, congenital heart disease, neonatal disease or admission to intensive care, prematurity or low birth weight, systemic disease associated with hypertension, or treatment with medications that raise blood pressure.
3) How should blood pressure be measured correctly in children?
Blood pressure should be measured after 5 minutes of rest, in a calm environment, with the child seated and the right arm supported at heart level. An appropriately sized cuff for the arm circumference is essential. At least three measurements should be obtained during the appointment, using the average of the last two readings. When values are elevated, confirmation by auscultatory measurement is recommended, particularly when the initial measurement was obtained using an oscillometric device.
4) How is blood pressure classified in children younger than 13 years?
In children
younger than 13 years, classification is based on
percentile tables adjusted for
age, sex and height. In simplified terms,
normal blood pressure is
; elevated blood pressure is between P90 and ; stage 1 hypertension corresponds to ≥P95 and ; and stage 2 hypertension is ≥P99 + 5 mmHg. If systolic and diastolic values fall into different categories, the higher category should be used.5) What reference values are used from the age of 13 years?
From the age of 13 years, absolute thresholds similar to those used in adults are applied: normal blood pressure is <120/<80 mmHg; elevated blood pressure is 120–129 mmHg with a diastolic value of <80 mmHg; stage 1 hypertension is 130–139 mmHg or 80–89 mmHg; and stage 2 hypertension is ≥140 mmHg or ≥90 mmHg. This rule simplifies interpretation in adolescents and helps prevent common classification errors.
6) When can hypertension be diagnosed?
The diagnosis of hypertension requires the
persistence of elevated values across
separate appointments, using the correct measurement technique. As a general rule, hypertension is confirmed when values consistent with hypertension persist over
three appointments. If blood pressure returns to normal during reassessment, for example to
, hypertension is not diagnosed and appropriate routine surveillance should be resumed. If the value falls into the elevated blood pressure range, corresponding to P90–P95, lifestyle measures should be reinforced and reassessment arranged within an appropriate interval.7) What should be done if the elevation does not persist and normalises before the third appointment?
If blood pressure decreases to normal values during reassessment, hypertension should not be diagnosed and routine surveillance should be maintained. If it decreases to the elevated blood pressure range, lifestyle intervention and reassessment, often after approximately 6 months, are recommended. Physiological variability, anxiety related to the clinical setting, or white-coat effect, and measurement technique may explain transient elevations, so diagnostic confirmation always depends on persistence.
8) When is the situation urgent?
Stage 2 hypertension requires prompt assessment, and the presence of symptoms suggests greater risk. Symptoms of severe hypertension should be sought, including severe headache, visual disturbances, vomiting, chest pain, dyspnoea, seizures or altered consciousness. Markedly elevated values, such as 30 mmHg or more above the 95th percentile, further support the need for urgent assessment. Symptomatic children or those with marked blood pressure elevation should be referred immediately. Asymptomatic children with persistent stage 2 hypertension require urgent hospital assessment.
9) Which lifestyle measures are recommended?
All children with values above the normal range should receive lifestyle intervention. Recommendations include maintaining a healthy weight, adopting a healthy diet with particular emphasis on reducing salt intake, limiting sugar-sweetened beverages, engaging in regular physical activity and reducing sedentary time. The family context should also be assessed, and sustainable measures should be reinforced, particularly when excess weight is present.
10) When should ambulatory blood pressure monitoring be considered?
Ambulatory blood pressure monitoring (ABPM) may be considered to confirm hypertension, particularly in persistent stage 1 hypertension, when white-coat hypertension or masked hypertension is suspected, and in children at higher risk, such as those with chronic kidney disease, diabetes or a history of prematurity with associated comorbidities. ABPM helps characterise the blood pressure pattern over 24 hours and supports clinical decision-making.
11) When should secondary causes be investigated?
In children and adolescents, hypertension may frequently be secondary, particularly in younger children and in stage 2 hypertension. Investigation should be considered when hypertension is confirmed, has an early onset, is markedly elevated, occurs in the absence of typical risk factors such as obesity, or is associated with findings suggestive of underlying renal, endocrine or cardiovascular disease. The decision depends on the clinical context and level of care, and assessment in a specialist hospital setting is often required.
