Blood Pressure Information
What is blood pressure? Why does it increase?
How do you lower your blood pressure?
Heart and circulatory disease is the UK's biggest killer and many of the major risk factors have no symptoms. Blood pressure is one of these 'silent' risk factors. If you have undergone a BlueSkies Health MOT and now wish to lower or manage your blood pressure, this information will help you do so.
NB The information on this page should not supersede that given by your GP or medical professional.
What is blood pressure?
Blood pressure (BP) is the force exerted on the artery walls by the blood as it circulates around the body. Your BP, at any point in time, will depend upon your activity level, hydration status, temperature, emotional state, posture, health and medication. BP is constantly changing, even at rest, because it rises as the heart contracts and falls as the heart relaxes.
Blood pressure is expressed in millimetres of mercury (mmHg) and is recorded as two values:
- The first number is Systolic Blood Pressure (SBP) and this is the pressure recorded when the heart contracts propelling blood around the body. Normal SBP in adults varies between 110 and 140mmHg.
- The second number is Diastolic Blood Pressure (DBP) and this is recorded when your heart relaxes allowing the blood to return to the heart to be redistributed. Normal DBP in adults varies between 60 and 90 mmHg.
BP is always recorded as SBP over DBP e.g. 132/85mmHg and the optimal BP for healthy adults is 120/80mmHg or lower.
For the latest research findings on blood pressure, click here.
Why does blood pressure increase?
BP can increase for a number of reasons.
Genetics
Genetics factors can result in elevated BP and an increased chance of developing hypertension (high BP). If one, or both, of your parents have (or had) hypertension, you have a higher risk of it.
Additionally, Asian and Afro-Caribbean people have a higher chance of being hypertensive. But remember, genetics only play a small part in determining your BP, it’s your lifestyle that can have the most dramatic effect on whether or not you become hypertensive.
Other factors
It is common to see an age-related increase in BP as our blood vessels begin to lose their elasticity. BP will also increase if blood vessels constrict or become narrowed for any reason, as is the case when atherosclerotic plaques are present.
Other factors that can increase your BP include:
- Poor diet – Diets that are high in salt increase the risk of developing hypertension as do diets that are low in fruit & veg.
- Physical inactivity – Inactivity is one of the biggest causes of hypertension and also increases the risk of obesity.
- Obesity – Being overweight increases the risk of hypertension.
- Smoking – smoking will increase your risk of developing hypertension.
- Alcohol – Alcohol can, in moderate amounts, protect against heart disease. However, higher intakes can increase BP and the likelihood of developing hypertension.
Why know your number?
As the British Heart Foundation so nicely puts it, ‘the higher your blood pressure, the shorter your life expectancy’!
Having hypertension (high BP) increases a person’s risk of having a stroke or a heart attack as well as their risk of kidney failure, sight problems and heart failure.
Hypertension is a condition that affects a large number of people but it is largely asymptomatic meaning that there are often no warning signs. It is a common condition – it is estimated that around one fifth of UK adults are hypertensive. This prevalence of hypertension increases with age – around 50%-60% of people aged 65-74 are hypertensive.
Many hypertensive people are not aware of their condition. This is dangerous as hypertension is one of the major risk factors for coronary heart disease (CHD) – CHD is twice as common in hypertensive patients compared to those with normal BP.
What is high?
As already mentioned, optimal BP for adults is 120/80mmHg or lower. A person is defined as hypertensive if their BP is 140/90mmHg or above. The following table shows the BP classifications.
|
Classification |
SBP (mmHg) |
DBP (mmHg) |
| Optimal |
<120 |
<80 |
| Normal |
<130 |
<85 |
| High Normal |
130-139 |
85-89 |
| Borderline Hypertension |
140-149 |
90-94 |
|
Grade 1 Hypertension (mild) |
140-159 |
90-99 |
| Grade 2 Hypertension (moderate) |
160-179 |
100-109 |
| Grade 3 Hypertension (severe) |
≥180 |
≥110 |
Classifications equate to those of the WHO/ISH. If SBP and DBP fall into different categories, the higher value is used for classification.
It is important to remember that a single, high BP reading does not necessarily mean that you have hypertension. What it does mean is that you should keep an eye on your BP and get it checked by your GP.
Although both SBP and DBP have clinical significance, the latest research suggests that SBP (the first number) is more closely linked to cardiovascular disease risk and other conditions such as kidney failure.
How do you lower your blood pressure?
If your BP is above 140/90mmHg, it is recommended that you have it measured by your GP if you have not done so already. Your GP will be able to make a diagnosis based upon your results and help you decide how best to manage your condition. There are several ways to improve your BP.
Drug therapy
If your BP is particularly high and/or you have other heart disease risk factors, your GP may suggest that you start drug therapy. There are several different types of BP-lowering drugs available and the type that is most suitable for you will depend on a variety of factors including your current BP, your age and any other conditions that you may have.
The information contained within this article does not cover the medications that can be used to manage BP – this is information that you should seek from your own GP should you require it. Instead, we discuss modifiable lifestyle factors that can help to improve your BP.
Modifiable lifestyle factors
There are several lifestyle factors that can influence BP as discussed previously. Making simple, easy to achieve adjustments to your lifestyle and your diet can have a dramatic influence on your BP and your heart disease risk.
Modifiable lifestyle factors include:
- Diet – reduce your salt intake, including salt hidden in processed foods and increase your intake of fruit & veg
- Physical activity – take part in regular, moderate intensity physical activity
- Weight – maintain a healthy weight
- Smoking – stop!
- Alcohol – stick to the recommended limits of 14units/week for women and 21units/week for men and avoid binge drinking
Further information
To go the other pages in this series, please click on the appropriate topic below:
For more information on how to make modifications to the factors that will help you to improve your blood pressure click here. You will be taken to the Member's Area of the BlueSkies website and will need your Member's Password to gain access.
If you are a BlueSkies Member, your password will have been e-mailed to you when you joined. If you have forgotten your password, please click here to receive your password reminder by e-mail.
If you have recently taken part in a BlueSkies Health MOT, you will have been given a temporary password to allow you to access this information. If you have forgotten your password, please contact the person within your organisation who organised the BlueSkies Health MOT. Alternatively, please e-mail us by clicking here and telling us where and when you had your Health MOT.
If you would like to become a BlueSkies Member, please click here for more information.
For more information on hypertension and how to manage this condition, you can also visit the following websites:
- The British Hypertension Society www.bhsoc.org
- The British Heart Foundation www.bhf.org.uk
- The International Society of Hypertension www.ish-world.com
NB The information on this page should not supersede that given by your GP or medical professional.