Causes of high blood pressure

To better understand the causes of high blood pressure it is important to realise that these factors will determine if you have primary or secondary high blood pressure.

Primary high blood pressure

In the vast majority of high blood pressure cases there is no identifiable cause. It is difficult to pinpoint the exact causes but experts agree that our lifestyles are a major contributor.

Lifestyle is just one of several risk factors which determine the likelihood of you developing high blood pressure.

These risk factors include:

• Age
• Ethnicity
• Gender
• Weight
• Lifestyle
• Chronic stress
• Family history

Some of these you cannot alter such as your age, gender, ethnicity and family history but others can be changed, for example your lifestyle.

So if you have a pre-determined risk factor which can not be changed, take a look at those which can be changed such as your lifestyle.

This type of high blood pressure is called primary high blood pressure or ‘essential hypertension’.

Age

The risk of high blood pressure increases the older you get. Basically, your blood pressure rises as you age which is mainly due to the fact that your arteries narrow over time. This is often a result of your lifestyle. So, an unhealthy lifestyle will contribute to this compared to a healthy one.

Half of all people aged over 65 have high blood pressure.

Ethnicity

Experts are unsure as to why high blood pressure is more common in African-Caribbean and South Asian peoples. But these ethnic groups develop high blood pressure at an earlier age and at higher levels than Caucasian people.

Gender

Men are at greater risk then women of developing high blood pressure although this tends to even out in middle age. From the age of 45 onwards both men and women are likely to have high blood pressure.

But once women have passed through the menopause they are more likely to have high blood pressure than men.

Weight

If you are overweight or obese then you are at greater risk of developing high blood pressure. Extra weight in the form of body fat puts a strain on the heart as well as the rest of the body and causes blood pressure to rise.

Lifestyle

This includes diet, exercise, smoking (if you smoke) and alcohol consumption.

If you eat a high fat, high salt diet, drink to excess, smoke and have a sedentary lifestyle then you are a risk of high blood pressure.

But it is possible to reduce your blood pressure levels by making a few changes to your lifestyle which includes stopping smoking, eating healthily, moderate alcohol consumption and taking exercise.

This is discussed in greater detail in our treating high blood pressure section.

Chronic stress

Some stress is good for us but long term chronic stress can be harmful both physically and psychologically. Many people adopt unhealthy habits such as smoking and excessive alcohol consumption as a means of dealing with stress but these are risk factors for high blood pressure.

If you suffer from severe stress, look at ways of reducing this.

Family history

You cannot change your family and if a family member has or has had high blood pressure then unfortunately, you are likely to develop the same condition.

If your father and/or brother had heart disease or a stroke before the age of 55 then there is a strong chance of you developing the same. High blood pressure is a risk factor for either of these diseases. It is as well to be aware of this and to have your blood pressure checked at regular intervals. Also have a look at your current lifestyle and see if you need to make any changes, e.g. eating less salt.

Secondary high blood pressure

There is another form of high blood pressure which develops as a result of an underlying medical condition or a definable cause. Examples of this include kidney infections, diabetes and lupus.

What conditions are likely to cause high blood pressure?

These include:

• Diabetes
• Kidney disease/kidney infection
• Hormone disorders e.g. Cushing’s syndrome
• Hardening of the arteries e.g. arteriosclerosis
• Disease of the body’s tissues e.g. lupus
• Excess alcohol consumption
• Pregnancy
• Oral contraceptives
• Some forms of medication, e.g. painkillers, antidepressants (e.g. Ibuprofen), steroids, diet pills etc.
• Recreational drugs, e.g. cocaine, crystal meth and amphetamines.
• Herbal remedies (these can occasionally cause high blood pressure)

Note: pregnancy and oral contraceptives are discussed in detail in our women and high blood pressure section.

This type of high blood pressure is called secondary high blood pressure or ‘secondary hypertension’. This accounts for around 5 to 10% of high blood pressure cases.

In many cases, treating the medical condition will reduce high blood pressure.

Contrary to popular belief, anxious or highly strung individuals are not at an increased risk of high blood pressure.

Some risk factors pose a greater threat to your health than others. For example, high blood pressure and smoking are far more of a risk than being overweight.

Plus you are a greater risk of heart disease or a stroke if you have more than one risk factor. So, if you are overweight, smoke and have high blood pressure then you have an increased risk of a heart attack or a stroke before you reach your 60’s.

Your ‘risk factor/s’will be assessed by your GP or practice nurse when determining your likelihood of developing heart disease or a stroke.