Hypertension was long considered an adult disease. We now know that about 3.5 % of children have confirmed hypertension — up to 25 % among children with obesity. Untreated, it shortens life expectancy. The good news: when caught early, outcomes are excellent.
The AAP 2017 guideline (Flynn et al., Pediatrics 2017) provides the tool — an age-, sex- and height-specific percentile table. Unlike adults, a single threshold doesn't fit. A child's reading must be placed within a percentile to be meaningful.
Why "120/80" tells you almost nothing in children
120/80 mmHg in a 5-year-old is clearly hypertensive (stage 2). In a 16-year-old it sits at the elevated/stage 1 border. Why? A 5-year-old is small. Their heart pumps against a shorter vascular tree, so the physiological pressure is lower. Pressure rises steadily with growth and maturation.
That's why pediatrics works with percentiles: where does my child sit compared to peers of the same age, sex and height? Only this comparison tells you whether a reading is concerning. Our pediatric BP calculator does that work for you.
The four risk zones
| Range | Zone | Action |
|---|---|---|
| < 90th percentile | Normal | Routine well-child checks |
| 90th – 95th | Elevated | Recheck in 6 months, lifestyle |
| 95th – 95th + 12 | Stage 1 hypertension | Two further visits, refer if confirmed |
| > 95th + 12 | Stage 2 hypertension | Evaluate within 1 week |
From the 13th birthday the AAP logic switches to AHA adult cutoffs: elevated ≥120/80, stage 1 ≥130/80, stage 2 ≥140/90. The handoff to adult care stays seamless.
Cuff size — the most common error
A cuff that's too small "pinches" and reads falsely high. In pediatrics this is rampant. Rule: the inflatable bladder must encircle 80 % of arm circumference with a width of about 40 % of upper arm length. In practice this often means an adult standard cuff — not a "child" cuff — once school age starts.
- Sit quietly for 5 minutes — no excitement, no exercise just before.
- Arm at heart level — supported, not held in tension.
- Multiple readings on multiple days — a single value is never diagnostic.
Causes — younger children vs adolescents
Younger children mostly show secondary hypertension: renal disease (reflux, glomerulonephritis), coarctation of the aorta, endocrine causes (thyroid, adrenal). Imaging often delivers the answer.
In adolescents 6+, primary hypertension dominates — closely linked to obesity, low activity, sleep apnea, and a positive family history. Lifestyle often beats any medication here.
What parents can do
- 60 minutes of activity daily — playground, biking, sports clubs. Drops BP by 5–10 mmHg.
- Low-salt, vegetable-rich diet — processed food is the salt trap. Cooking from scratch beats any diet plan.
- Check sleep — 9–11 h for school-age, 8–10 h for teens. Investigate snoring (OSA!).
- Limit screen time — < 2 h passive media. More movement, less snacking.
- Address overweight — even 5 % weight loss measurably lowers BP.
Related topics & calculators
- How to measure blood pressure — technique, cuff and pitfalls for adults and children. See the measurement guide.
- Child growth percentile — your child's height and weight in context. See the growth chart guide.
- Child medication dosage — weight-based dosing made safe. See the dosage calculator.
Classify your child's blood pressure now
AAP 2017 percentiles, anonymous, instant. With thresholds and recommendation.
Open the pediatric BP calculator →Frequently asked questions
From what age should BP be measured?
From age 3, at every well-child visit. For children with risk factors (preterm birth, obesity, kidney disease, congenital heart disease) earlier and more frequently. Infants under 1 year use different reference values.
What is "white-coat hypertension"?
Elevated readings only in the clinic, normal at home. Affects up to 30 % of children. Ambulatory 24-hour monitoring resolves it — and often spares unnecessary therapy.
Are medications needed?
Only after 6 months of lifestyle intervention, or for stage 2, secondary causes, or end-organ damage. First-line is usually an ACE inhibitor or calcium channel blocker — pediatric cardiology decides.
Which symptoms are red flags?
Severe headache, vision changes, vomiting, unexplained nosebleeds, chest pain, or altered mental status — call 911 / go to the pediatric ED. Don't wait it out.