Nieman: High blood pressure not just an issue for adults

One of the reasons why I decided to specialize in pediatrics is that it offers many opportunities to practise preventive medicine.

Before there was a good vaccine for childhood meningitis, it was not uncommon to find a child in the ICU with a neurologist hovering around, discussing with petrified parents how the child’s brain may have been permanently damaged. Since the introduction of a safe and effective vaccine to prevent meningitis, this ICU image is now part of history. Other areas of prevention are less black and white, but rather grey.

Over the past 40 years, I have become more interested in long-term prevention; I have come up with the term “long-haul medicine.” ?

Does what we do as pediatricians make a difference later in life when our patients shave, turn grey or wonder about their lifespan and even their healthspan? Over the long haul, can we assume that the fuse is lit in childhood and the dynamite explodes in adulthood?

High blood pressure (hypertension or HT) is often called “the silent killer” because, in the majority of cases, there are no symptoms. HT affects about 40 to 50 per cent of adults and is a major contributor to stroke and heart disease.

In the pediatric population, the estimated incidence is close to five per cent. An important question is whether pediatric HT leads to problems in adulthood. Even though there are still major research gaps to address the exact trajectory of HT, it makes sense to screen children and teens for HT and embark on treatment to reduce later adverse outcomes.

Experts divided HT as primary and secondary. Primary means there are no renal diseases, endocrine abnormalities, medications which elevate the blood pressure (BP), coarctation of the aorta, neurological causes or rare conditions such as neuroblastoma, neurofibromatosis or tuberous sclerosis.

Efforts to standardize definitions and practice guidelines for the diagnosis and treatment of HT in youth began in 1977. Since then pediatric guidelines have undergone five iterations with the most recent guideline published seven years ago by the American Academy of Pediatrics.

HT is currently defined as repeated systolic or diastolic BP above the 95th percentile for patients aged one to 12 years and a BP more than 130/80 mmHg for patients 13 years and older.

However, it gets more complicated than mere percentiles or number discussions because obtaining BP measurements depends on the location (a clinic, at home or ambulatory methods throughout the day) the gender of a child, the height, the BMI, the size of a cuff around the arm, the time of day, the number of times one has to take the BP to make the actual diagnosis and the attire of the doctor.

There is a condition known as “white coat hypertension” which I suspect is less and less useful given the fact that the vast majority of pediatricians in 2024 have stored their formerly worn white coats in far-away closets.

Typical of academic minds, always aiming for perfection and accuracy, the consensus is that ambulatory blood pressure monitoring (ABPM) is the gold standard. It is indeed accurate and may even “catch” masked HT – a condition where the BP is normal in a clinic but elevated in the community. ABPM is not a practical tool for primary care doctors.

Primary care clinicians are encouraged to start measuring BP at age three. This takes time and if the cuff size is wrong may lead to false numbers. These numbers are complicated and only a doctor with a photographic mind can remember the exact numbers, corrected for age, gender and height. Some practitioners keep printed graphs of numbers by the BP machine; others go paperless and use an app on their smartphones or computers.

If an elevated BP is identified, experts suggest that the patient return – twice more and only if the BP elevation is consistent at three visits, is a diagnosis made.?

After the diagnosis is confirmed, lifestyle changes are discussed and hopefully put into regular practice. The obvious common sense and eternally difficult habits are: eat less salt, get active, lose weight and control stress.

Sleep specialists who see patients for obstructive sleep apnea are key players in reducing HT or reversing it. Research in the Journal of Psychosomatic Medicine confirms that an extra hour of sleep reduces BP and so does meditation and mindfulness training in youth.

There are medications to be used particularly when lifestyle changes fail to drop the BP, but even in the 2017 guidelines from the AAP, there is no consensus on which medication is the best.

If HT is called a silent killer in adults, I tend to think of it as the “silent set-up” in children and youth. The longer HT is not diagnosed or treated, the more we have to look at target organ damage – the eyes, kidneys and left ventricle of the heart. An enlarged left ventricle spells future trouble.

?For more information, visit?www.kidshealth.org/en/parents/hypertension.html

Dr. Nieman is the founder of Centre 70 Pediatrics. He has written monthly columns for the Herald since 1999.

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