The ABCs of blood pressure

Is your blood pressure too high or too low? It can be affected by a number of factors throughout your life. Here's what you need to know about hypertension and hypotension.

Blood pressure in Canada

According to the Canadian Health Measures Survey (CHMS) conducted from 2016 to 2019, 23% of people surveyed between the ages of 20 and 79 reported being diagnosed with hypertension. It’s even more prevalent with age and for those who are overweight. Among those over 60, one in every two people has high blood pressure!

What is blood pressure?

Blood pressure is the pressure of blood pushing against the walls of your arteries. It fluctuates throughout the day based on emotions, digestion, physical activity or stress. It drops at night and goes up again early in the morning.

Is your blood pressure in the optimal range?

Find out by talking to your doctor. You can also check your blood pressure at a pharmacy, or even measure it yourself.

Blood pressure is measured in millimetres of mercury (mmHg) using a blood pressure monitor. It’s expressed using two numbers (an upper number over a lower number). The systolic pressure (the higher number in mmHg) is the pressure in the artery when the heart contracts. The lower number (in mmHg) indicates the diastolic pressure, which is the pressure in the artery when the heart relaxes between beats. The average of your home blood pressure readings should be less than 135/85 mmHg. If you have diabetes, it should be 130/80 mmHg.

How to check your own blood pressure at home

Checking your own blood pressure at home using an automatic blood pressure monitor is highly effective as a preventive measure. Hypertension Canada recommends a number of gold-rated devices with different types of cuffs, so check their website before buying one. It’s a practical gift for you or your loved ones. Here are a few tips for checking your own blood pressure:

  • Measure your blood pressure (BP) after sitting for five minutes.
  • Support your back and keep your feet flat on the floor.
  • Don’t cross your legs.
  • Use the right size cuff (a cuff that’s too small may overestimate your blood pressure).

Consult your health care professional to find out what size to get or for any other questions about using the blood pressure monitor.

High blood pressure

Many people with high blood pressure don’t experience any symptoms. Hypertension is an insidious, terrible disease that’s often called the silent killer. For most people, the cause is unknown. For others, the cause is renal or vascular impairment. Some people may experience:

  • headaches
  • nosebleeds
  • buzzing in the ears
  • dizziness
  • visual problems

What are the dangers of high blood pressure?

Hypertension that’s not controlled through blood pressure medication can lead to a number of complications linked to the development of heart disease. These complications can affect the kidneys, arteries or eyes, and include:

  • stroke
  • cerebral hemorrhage
  • myocardial infarction or angina
  • heart failure
  • atrial fibrillation
  • left ventricular hypertrophy
  • leg pain or pain when walking (claudication)
  • end-stage renal disease
  • certain dementias
  • diabetic nephropathy (kidney disease)
  • erectile dysfunction
  • retinal bleeding
  • premature death

What factors contribute to high blood pressure?

In the long term, a number of unhealthy lifestyle habits can contribute to high blood pressure. Tobacco, alcohol, ultra-processed foods such as fried food, food that's very high in sugar, junk food, a sedentary lifestyle, stress, and forgetting to take your blood pressure medication all increase the risk factors, allowing blood pressure to rise abnormally for a long period of time.

How can you reduce the risk of hypertension and its complications?

By adopting a healthier lifestyle, you can further reduce your risk of developing this disease. Here are a few changes you could make:

  • Quit smoking
  • Reduce your salt intake to less than 2,000 mg/day
  • Do at least 30 minutes of physical activity a day or exercise regularly
  • Limit your alcohol consumption
  • Maintain a healthy weight
  • Learn to better manage your stress

Low blood pressure. What are the dangers of low blood pressure (hypotension)?

Blood pressure lower than 90/60 mmHg is considered more of a symptom than a health problem in itself. Many high-level athletes have low blood pressure. Blood pressure that’s too low to send enough oxygen to the brain may cause dizziness or fainting, and can be brought on by a number of things:

  • changing positions too quickly after eating a large meal
  • a heart problem
  • a neurological problem
  • certain arrhythmias
  • dehydration
  • taking medication
  • excessive heat from a sauna
  • hormonal changes

The important thing is to find the cause of your low blood pressure so it can be better treated.

How can you reduce the symptoms of hypotension?

A few preventive measures can help you avoid certain symptoms:

  • Don’t stand up too quickly.
  • Stay well hydrated by drinking enough water (8 glasses a day, and even more in hot weather).
  • Limit alcohol or cannabis.
  • Don’t cross your legs.

In short, hypotension and hypertension have an impact on your overall health. Hypertension can be treated with a combination of blood pressure medications, which are very effective at preventing complications. One in six Canadians don’t even know they suffer from hypertension.The best thing you can do is adopt healthy lifestyle habits and check your blood pressure regularly. If necessary, don’t hesitate to talk to a health care professional.