“What are you doing?”
Patient
I often get asked this question while taking blood pressure (BP).
Interestingly, many patients need to learn what BP is and why we check it.
“I wrote this BP basics blog post to educate hypertensive patients who want to know more about their illness.”
Are you ready for your introductory lesson on blood pressure numbers by age?
- What do the numbers mean?
- And do blood pressure goals vary by age?
We often think of high BP as something our parents are diagnosed with in their 50s.
But high blood pressure in your 20s? Is this possible?
Unfortunately, it is a reality.
Over the past few years, I have seen more and more young adults in their 20s and 30s with high blood pressure. This is terrifying.
What is the reason for this?
“In my opinion stress, poor diet, and bad lifestyle choices tip a genetic tendency over the edge.”
When any adult patient comes to my practice, I check their BP, no matter their presenting complaint. It could be a sore ear, a rash, or constipation.
Now and then, I find an unexpected high blood pressure.
Photo by Andrea Piacquadio: https://www.pexels.com
Are you in your 40s, 50s, or older and diagnosed with high blood pressure?
Don’t stop reading this article. All the basics still apply to you; only your blood pressure numbers goal might vary slightly by age.
Let’s go back to the basics.
Also read: Blood pressure treatment ∣ Are there magic solutions?
What is blood pressure?
Simply put, it is the pressure in the arteries.
First, a simple anatomy lesson to help you better understand the basics of BP.
- The heart has a right and a left side.
- The left side pumps oxygenated blood from the lungs into the body.
- The blood leaves the left ventricle into arteries via the aorta.
- The left ventricle squeezes and pushes blood into the arteries. We call this contraction systole. The time of highest pressure in the artery is during systole.
- The left ventricle then relaxes as it refills. This phase is diastole, and the pressure is now at its lowest.
We use the brachial artery to measure blood pressure.
This blood vessel runs down the front of your arm.
A cuff is applied on the upper arm at the level of the heart, best taken seated.
Understanding the reading
I’m sure that by now, you’ve heard a blood pressure reading as “a number” over “a number,” for example, 120 over 80.
- The upper value is the systolic reading—the pressure in the artery when the left ventricle is contracting. Now, the pressure is at its highest. (SBP)
- The lower value is the diastolic reading—the pressure in the artery when the left ventricle is relaxed. Now, the pressure is at its lowest. (DBP)
Manual versus digital readings
A manual reading means the measurement is taken using a stethoscope to listen to the pulse.
A sphygmomanometer is a machine used to take manual blood pressure readings.
“I’m an old-school-manual-BP-reading-girl who likes to hear the reading. I trust my ears!”
The original meters, still available today, contain mercury. The mercury pushes up a calibrated glass tube as the pressure increases.
This is the origin of the international unit of blood pressure measurement, mmHg (millimeters of mercury).
Alternatively, manual sphygmomanometers might have a dial, also in mmHg.
Most clinics and hospitals prefer digital readings, ensuring consistency between different operators.
Digital readings are what you will use for home BP monitoring. An automated machine pumps up the cuff and gives you a measurement on a screen.
What is normal and what is not?
“I use the International Society of Hypertension (ISH) recommendations as a guide.” 1
Watch the video below moving from normal to dangerous BP.
Do target blood pressure numbers by age vary?
This is a controversial subject, but generally, the guidelines are ‘the lower, the better.’
How low is good enough to prevent blood vessel disease and death?
SBP of 120 to 124 mmHg according to trends found in a study that analyzed data from 42 trials. 2,3
Should everyone be treated to the same goal?
Some treated patients don’t tolerate their new normal blood pressure.
They feel tired and dizzy. This is especially true in older people, who might already be at risk of falling. So, should goals be relaxed?
A Circulation Journal article quoted a novel proposal by the American Heart Association,
“… consider a simple age/BP formula: optimal adult BP levels should be about 100 plus 1/2 the patient’s age. This would correspond to 120 mm Hg for patients aged 40 years, 130 mm Hg for patients aged 60 years, and 140 mm Hg for patients aged 80.” 4
The article notes that this suggestion is not evidence-based. 4
Another proposed guideline by the ISH is: 1
- < 65 years, between 120/70 and 130/80, if tolerated.
- >= 65 years, < 140/90, if tolerated.
“I try to get my patients’ BPs as low as possible without making them feel unwell.”
Why is high blood pressure harmful?
Hypertension is an independent risk factor for vascular disease. It contributes to heart attacks, strokes, and kidney disease.
Here are the reasons why:
High blood pressure damages arteries
- When the pressure on the arteries is high continuously, they stretch under strain. Over time, this will damage the walls of the vessels with tears. These tears, under constant pressure, may burst.
- Damaged, irritated arteries are easily inflamed. This allows bad cholesterol (LDL) to form plaques in the walls.
- The plaques and inflammation attract platelets that stick and cause clots.
High blood pressure enlarges and damages the heart muscle
Increased pressure in the arteries means the heart needs to pump harder against the pressure.
Like any muscle that is working harder, it gets thicker. This makes the heart muscle less flexible and, thus, a less effective pump. The increased muscle bulk requires more oxygen, but the hypertension-damaged blood vessels supply less oxygen. A vicious cycle begins.
How will I feel if my blood pressure is high?
Hypertension is known as the silent killer because there are no specific symptoms.
You have no idea you have it.
This is why it is so important to have an annual check-up.
Where can I have my blood pressure checked?
Most pharmacies, clinics, and corporate companies have a nursing sister to measure your BP.
You can also ask your family doctor to check it at your next visit. At the same appointment, ask about other age-appropriate screening tests.
If you are diagnosed with high blood pressure, you should be aware of other risks for arterial disease.
The most common factors are:
- high cholesterol,
- smoking, and
- diabetes.
Keep following my blog weekly for articles on the above topics.
What are the causes of high blood pressure?
The causes are discussed in my blog on blood pressure treatment.
Knowing the causes = Understanding BP treatment
References
- Unger, T., Borghi, C., Charchar, F., Khan, N. A., Poulter, N. R., Prabhakaran, D., Ramirez, A., Schlaich, M., Stergiou, G. S., Tomaszewski, M., Wainford, R. D., Williams, B., & Schutte, A. E. (2020). 2020 International Society of Hypertension global hypertension practice guidelines. Journal of hypertension, 38(6), 982–1004.
- Reboussin, D. M., Carey, R. M., & Whelton, P. K. (2019). Evidence Supporting the Blood Pressure Treatment Goal of Less Than 130/80 mm Hg. Hypertension (Dallas, Tex. : 1979), 73(5), 972–974.
- Bundy, J. D., Li, C., Stuchlik, P., Bu, X., Kelly, T. N., Mills, K. T., … & He, J. (2017). Systolic blood pressure reduction and risk of cardiovascular disease and mortality: a systematic review and network meta-analysis. JAMA cardiology, 2(7), 775-781.
- Messerli, F. H., Bangalore, S., & Messerli, A. W. (2018). Age, Blood Pressure Targets, and Guidelines: Rift Between Those Who Preach, Those Who Teach, and Those Who Treat? Circulation, 138(2), 128–130.
