High Blood Pressure
While high blood pressure, also known as hypertension, can be related to a number of conditions including diabetes, thyroid problems and sleep apnoea, it can also be caused by lifestyle factors, a family history or the normal ageing process. In this detailed article, our Consultant Cardiology team answers commonly asked patient questions.
What is hypertension?
Hypertension is defined as high blood pressure, which we would usually consider to be any reading of systolic blood pressure greater than a 140/90mmHg (millimetres of mercury).
There are many ways of diagnosing high blood pressure but today, an advisable approach uses a twenty-four hour blood pressure monitor; this allows you to check your blood pressure over the course of one day as you complete your everyday activities.
We do not advocate for the diagnosis of high blood pressure to be made based purely on a single or handful of readings during a GP or cardiology clinic visit; this is because patients can, sometimes, be slightly anxious in an unfamiliar environment and this can give a reading that does not represent your actual blood pressure.
Why is it important to treat high blood pressure?
High blood pressure is a condition that can negatively affect your health without you being aware that you are suffering from it. We know that if you have high blood pressure, for a number of years, this can negatively affect the heart by causing the heart muscle to thicken making it more difficult to relax. High blood pressure can also affect your kidneys and it is one of the most important risk factors when it comes to strokes.
In practising preventative medicine, it is important that you have your blood pressure assessed at least once a year. If there are any concerns that your blood pressure could be high, this should be confirmed with a twenty-four hour blood pressure monitor and, if the assessment shows that your blood pressure is high, then treatment considered.
What are the symptoms of hypertension?
High blood pressure is often described as a silent killer because most patients will have no symptoms. Undetected high blood pressure will continue to have negative effects on your health but you will likely not be aware of them until significant or irreversible damage has taken place. If your blood pressure is extremely high you may complain of headaches or blurred vision.
How is hypertension diagnosed?
Normally we are alerted about a patient having hypertension because they have visited their GP or they themselves have taken a few readings at home which show greater than expected blood pressure readings. This, however, usually needs to be confirmed with a twenty-four hour blood pressure monitor. The monitor is a cuff on your arm which generates a number of readings, during both day and the night. Those results are then analysed and, if we find that your blood pressure is significantly high, we need to think about the reasons why that is the case and consider treatment.
High blood pressure in general can be defined in two categories: primary (also known as essential) hypertension and secondary hypertension.
Essential hypertension usually doesn’t have a single, specific cause but rather multifactorial causes, which can include your lifestyle, a family history as well as other medical conditions. In these cases, assuming that simple lifestyle measures cannot effectively reduce your blood pressure, additional treatment may be required in order to achieve this.
Secondary hypertension is far less common and is usually the result of other underlying factors. This could include problems with hormones, for example high levels of cortisol or catecholamines (like adrenaline), or be the result of structural abnormalities in the arteries that supply the kidneys or the aorta (the big vessel connecting the heart to the rest of the body).
What causes hypertension?
In more than ninety per cent of cases, hypertension is primary and doesn’t have a single identifying or specific cause. It can be something that develops with age, related to a positive family history, lifestyle factors and other medical conditions.
If you are diagnosed with hypertension, there are some important lifestyle changes you can make which will help to reduce your blood pressure. In essence, these modifications relate to leading a healthier lifestyle by reducing your salt intake, reducing your stress levels and exercising more.
Secondary causes of high blood pressure (which, as mentioned, are far less common) can include aortic coarctation where there is narrowing in the early segments of the aorta. This is something that you would typically be born with. Hypertension may also result from a narrowing of one of the arteries which supply the kidneys. Abnormalities with thyroid function and adrenal gland problems can also cause high blood pressure as can diabetes, kidney problems and conditions like sleep apnoea.
How is hypertension treated?
The key thing about treatment for hypertension is that we get high blood pressure under control. How we achieve this will depend on how high your blood pressure is and whether this is primary or secondary. If it is only marginally raised, simple lifestyle measures can have make a significant impact. These include:
Reducing salt intake in your diet
Improving the amount of physical activity that you do
Reducing your alcohol intake
Trying to lose weight if you are overweight
Although simple lifestyle changes can have some impact for patients, our experience shows that with very elevated blood pressure, they don’t tend to reduce your blood pressure enough. Therefore, the next step in cases of primary hypertension, is the initiation of medication.
To determine which type of medication should be used, we consider your age and the results of some routine blood tests (which we will perform). Commonly used, first line treatments for hypertension tend to be angiotensin receptor enzyme inhibitors, such as Ramipril and angiotensin receptor II blockers such as Candesartan; both can be very effective.
Often, combination treatment is required which usually involves the introduction of at least two types of anti-hypertensive medication. These include calcium channel blockers as well as thiazide diuretics amongst others.
If you require medication to treat your hypertension, the details of your medication regime will be discussed in more detail with your cardiologist. Sometimes, it can take a bit of time to get the blood pressure under control as we introduce new tablets and work to achieve the optimal dose and a regime that works for you.