Hypertension (high blood pressure)
What is hypertension?
Blood pressure is a force of blood pushing against the arteries as it pumps out of the heart. When this pressure is high it is called hypertension. It is recorded as 2 numbers, for example, 120/80. The top number (systolic) is the pressure in the arteries when the heart contracts. The bottom number (diastolic) is the pressure in the arteries when the heart rests between each heartbeat. Blood pressure is measured in millimetres of mercury (mmHg).
High blood pressure, or hypertension, is defined as a blood pressure of over 140/90mmHg and means that your heart has to work harder to pump blood around your body. Untreated, hypertension raises the risk of heart disease, stroke and kidney disease.
What do the numbers mean?
What should my blood pressure target be?
The target should be less than 140/90 mmHg, but ideally, it should be below 120/80 mmHg as this reduces your risk of early death by nearly 1/3 and the risk of heart attack by 25%.
How will I know if I have hypertension?
You will not know if you have hypertension unless your health care provider measures your blood pressure. High blood pressure itself has no symptoms. It is, however, a strong risk factor for developing heart disease and kidney damage. In general, the higher your blood pressure, the greater the risk.
If you have diabetes, you are aged over 60 years or have other risk factors for high blood pressure your blood pressure should be checked at least once a year. If you have a lower risk of high blood pressure your blood pressure should be checked at least once every 5 years.
What are the causes of hypertension?
In most cases the cause of high blood pressure is unknown. This is known as primary or essential hypertension and tends to develop gradually over many years. There is usually a family history of high blood pressure
A minority of people have high blood pressure due to an underlying health condition (secondary hypertension) which includes:
- Kidney problems
- Certain medication such as birth control pills
- Adrenal gland tumours
What can I expect when I have my blood pressure checked?
Blood pressure is usually measured using a device called a sphygmomanometer, or blood pressure monitor, where a cuff is applied to the upper arm. In preparation:
- Do not smoke, exercise, drink caffeinated drinks or alcohol within 30 minutes of measurement.
- Rest in a chair for at least 5 minutes with your left arm resting comfortably on a flat surface at heart level.
- Sit calmly and do not talk. Make sure you are relaxed.
- Two readings will be taken 1 minute apart.
Several tests may be done by your health care provider to look for the cause of your high blood pressure, its potential effects and risk factors for heart disease, for example blood sugar (to check for diabetes), blood cholesterol, kidney function and a urine test.
You may also have an ECG (heart tracing)
What are the risk factors for hypertension?
The following factors increase the risk of high blood pressure:
- Increasing age
- Family history
- Overweight and obesity
- Not being physically active
- Too much salt in your diet
- Drinking too much alcohol
- Chronic stress
- Certain chronic conditions such as diabetes and kidney disease
How is hypertension treated?
Treatment varies from one person to the other. Some people can reach their blood pressure targets with lifestyle changes alone while others will need medication. Your doctor will help you find a treatment plan that is right for you.
Make wise food choices. Try to reduce the sodium in your diet and eat a variety of foods with nutrients that help lower blood pressure such as potassium, calcium and magnesium.
- Fruit and vegetables contain potassium which helps to balance out the negative effects of salt on your blood pressure. Try to eat at least 5 different portions of fruit and vegetables a day.
- Switch to low-fat dairy products.
- Choose high fibre foods
- Eat unsalted nuts and other healthy fats in small portions
- Choose lean meats, poultry and fish
- Eat legumes such as lentils and beans
- Add very little or no salt to your food during cooking and at the table. Flavour your food with salt-free herbs and spices instead.
- Use healthy cooking methods such as baking, roasting or grilling
- Avoid processed foods, ready meals, takeaways and sauces from jars as these tend to contain a lot of salt
Other lifestyle changes that can help control blood pressure are:
- Lose weight if you are carrying a few extra pounds
- Keep physically active. Aim for at least 30 minutes of physical activity, 5 days a week
- Stop smoking and reduce alcohol intake
- Try to get at least 7 hours sleep at night
- Stress management
You may be started on a tablet that will help lower your blood pressure. Not everyone takes the same blood pressure medications and many people will require 2 or more medications to keep the blood pressure under control. Your doctor will talk to you about the different medications if your blood pressure remains above target despite your lifestyle changes.
It is important to have regular blood pressure measurements and follow up appointments to ensure your tablets are the right dose for you.
By Dr Mohgah Elsheikh