man measuring his blood pressure

The causes of hypertension can vary and can be difficult to establish. Narrow, stiff or clogged arteries lead to higher blood pressure when your heart starts pumping more blood – be it because you are exercising or stimulated in some way (e.g. excitement, anger, sexual arousal).

In more than 90% of patients, it is very difficult to determine one clear-cut cause of hypertension and most doctors suspect, that there is a variety of issues at play.

That's why it's important that you get a medical check-up so that your doctor can try to determine the reasons for your high blood pressure.

If you have been diagnosed with high blood pressure, you can order a repeat prescription online for your medication for hypertension. Our doctors can prescribe most UK brands (Diovan, Aprovel, Amias) and dispatch you a 3-6 month treatment via our partner pharmacy.

To get your delivery on time please see our working hours over the holiday period.

What causes high blood pressure?

Blood pressure is the result of the amount of blood pumped through your body by the heart and the resistance to the blood flow from the walls of your arteries. High blood pressure occurs when your arteries cannot dilate properly to accommodate changes in blood flow.

High blood pressure takes many years to develop, and usually shows no symptoms at all. Most people will discover they have it when they go for a medical check-up, suffer a heart attack or develop erectile dysfunction.

As we all age, our arteries become stiffer and less flexible, therefore a certain increase in blood pressure is normal over the years as arteries are less flexible to variations in the blood flow.

However, abnormally high blood pressure is a real problem that leads to heart attacks and strokes. Over time, the excessive pressure on the walls of your arteries will cause damage to the arteries themselves.

Technically speaking, what causes high blood pressure are excessively narrow, stiff and/or clogged arteries do not allow for the blood to be distributed throughout the body. The challenge becomes understanding exactly what causes this narrowing, stiffing or clogging.

On the upside, it’s very quick and easy to diagnose hypertension. After that, you need to work with your GP, who will develop a treatment plan for you.

Essential (or primary) hypertension

The most common form of high blood pressure is called essential hypertension. It represents about 90-95% of cases of hypertension and doctors usually cannot identify the exact reasons for a high blood pressure of this type.

The physical cause of essential hypertension is a narrowing of the arteries that causes blood pressure to increase (too much blood trying to get through too narrow arteries). However, just what exactly causes this narrowing remains unclear, although doctors consider that a combination of factors will usually cause this disease.

The factors include (full list in the "risk factors" section):

  • Lifestyle
  • Diet – too much fat, salt or coffee
  • Age
  • Gender – men are more at risk than women
  • Ethnicity
  • Genetics (family history of hypertension)

Essential hypertension develops slowly over the years, which is why it is symptom-less (or asymptomatic) most of the time – until something triggers a heart attack, stroke or another condition.

Secondary hypertension

The second most common cause of high blood pressure is called secondary hypertension. It represents 5-10% of cases of hypertension and is due to an underlying condition.

The causes of secondary hypertension include: kidney disease, hormonal disease (e.g. gland tumour, hyperthyroidism), lead poisoning, head injuries and pregnancy.

Many of these causes of secondary hypertension are temporary and/or curable. Some medications and drugs can also cause secondary hypertension. These include antidepressants, cocaine, amphetamines, NSAID (non-steroidal anti-inflammatory drugs such as aspirin or ibuprofen in high quantities), decongestants, etc.

Less common causes

Isolated systolic hypertension is a much less common cause of hypertension. It happens, when only the first number of your blood pressure is too high, for example 140 in 140/80 (read 140 over 80)

This number represents the systolic blood pressure (when blood is pumped into the vessels), as opposed to the diastolic blood pressure (the second number, when the heart is at rest).

This disease causes high blood pressure only when the heart is pumping blood, after which the blood pressures goes back to normal. This creates a huge chronic difference in blood pressure, which swings up and down, and can put a big strain on your arteries.

Causes of isolated systolic hypertension (or ISH) include advanced age, anaemia (lack of red blood cells), thyroid hormone diseases and heart conditions.

Another reason for high blood pressure – called white-coat hypertension – is not as serious as the other types and happens because of the stress of being in a hospital or clinic and receiving treatment there. It is not really a case of high blood pressure as a condition but is simply a case of elevated blood pressure due to stress.

This can lead to certain misdiagnosis, so try to relax as much as possible when at the hospital and/or with your doctor.

High Blood Pressure Risk factors

Lifestyle-related risk factors:

  • Smoking raises your blood pressure, and most importantly it damages your arteries in the long run, causing them to narrow down
  • Lack of exercise: the arteries will lose more quickly the ability to adapt to changes in blood flow (by expanding or narrowing), thus leading to a faster aging and hardening of your arteries
  • Obesity: as your weight increases, you need more blood to “feed” your tissues in oxygen and nutrients. This means that your arteries are gradually transporting much more blood than they were originally “designed” for
  • Stress, which may trigger strokes and heart attacks as it can temporarily lead to huge increases in blood pressure
  • Unhealthy diet: too much alcohol, salt, coffee as well as lack of potassium and vitamin D will contribute to increasing your blood pressure. Binge drinking also damages the heart

Then come the “hard to change” background-related risk factors:

  • Age: the older you get the higher your blood pressure is because of the natural hardening of the arteries, but also because of lack of exercise
  • Family background: there is a genetic aspect to hypertension which is often transmitted within families
  • Ethnicity: some ethnic groups are more at risk of high blood pressure than others, for example people from South Asian (e.g. India) and Caribbean origins

And finally the disease-related risk factors:

  • High cholesterol, which agglutinates in your blood vessels and in the long run causes them to become narrower and narrower
  • Diabetes, with 30% of people with type 1 diabetes and 50% of those with type 2 who will develop high blood pressure over time
  • Kidney disease

There is a whole range of other diseases that can contribute to high blood pressure. Many are rather uncommon causes, so when in doubt it’s best to consult your doctor – online or in real life – to better understand what causes high blood pressure in your case.

You should also know, that risk factors usually add up, meaning that the more risk factors you accumulate (e.g. 65 year old overweight smoker with diabetes), the more you increase your risk of high blood pressure, heart attack or a cardiovascular disease (i.e. heart and blood vessels disease).

How common is high blood pressure in the UK ?

In the UK, as well as in many other countries, hypertension remains under-diagnosed. Tens of thousands of people are at risk and unaware their condition... until the day they eventually suffer from its consequences - be it stroke, heart attack or impotence.

In men aged over 40-45, about 30-35% suffer from high blood pressure and around 25% of women the same age have hypertension.

About half of British people aged over 65 have hypertension.

In people over 75 years old, about 75% of men and 65% of women have high blood pressure.

The threshold that determines who has hypertension and who hasn’t, is a blood pressure reading equal to or over 140/90 (140 over 90). The higher the blood pressure is, the greater the risks of developing serious conditions and suffering from severe strokes.

The lack of treatment and screening of high blood pressure means that too many people in the UK suffer from this preventable disease. Thousands of lives could be saved every year if people age over 50 had their blood pressure checked regularly.

Measuring blood pressure

You need to understand what causes high blood pressure to realise whether you are part of the population at risk or not.

If you worry you might be at risk, get into the habit of getting your blood pressure checked regularly – every couple of years or so. This way you can know when the risks get too high and treatment along with lifestyle changes are needed.

Once you know that you are at risk (e.g. diabetes, age over 65, mild hypertension) you need to get your blood pressure measured at least once every year.

To get your delivery on time please see our working hours over the holiday period.