Hypertension-it can CREEP up on you!
“As the years count and the stresses surmount, hidden behind the eyes with the cholesterol rise, lays a secret to the demise from Hypertension!”
What is Hypertension and why does it matter?
‘Hypertension’ is essentially high blood pressure that is above the ‘normal’ range. It is of medical significance because it is a condition that can easily go undiagnosed for many years as it does not manifest itself with specific symptoms, which explains why it is often referred to as the ‘silent killer’. It is potentially life-threatening if left untreated for prolonged periods.
In 2006, it was concluded that 37% of adults in the UK had hypertension, ‘diagnosed that is’. It is anticipated that we are only looking at the tip of the ice-berg representing the hypertensive population, which is why most doctors now screen for it during routine consultations with their patients.
What people often will present with are the complications as a result of the hypertension. This is the result of damage to the organs receiving blood at high pressure, otherwise referred to as end-organ damage (i.e. the kidneys, heart, and brain). This can present as renal failure, heart failure and stroke in clinical practice.
What does ‘systolic’ and ‘diastolic’ mean?
The term ‘systolic’ refers to the system pressure of blood flow from the heart, during the state of ‘systole’ (contraction cycle). ‘Diastolic’ refers to the system pressure when the heart is in the relaxation stage (refilling cycle), otherwise termed ‘diastole’.
How is blood pressure measured?
This is measured in the clinical setting either using a manual (mercury) sphygmomanometer (cuff width should be >40% of the arm circumference) or the newer automatic electronic blood pressure recording devices.
It is important to know that some of the automatic devices are not very accurate, which can cause added concerns to patients who are doing home monitoring.
The home monitoring devices are good for those patients who suffer from ‘white coat syndrome’. This occurs when patients see their doctor, and as a response to the situation, almost ‘fear-like’ (fright, fight and flight); the body’s natural steroid hormones are raised, giving a ‘falsely’ high reading.
For more information on recommended and validated home automatic monitoring devices go to the British Hypertensive Society (BHS) website at:
-click on BP monitors
-scroll down and click on automatic blood pressure devices
It will then give you a list of monitors, their price range, outlets of where they are sold, and most importantly whether they have been approved by the BHS.
What is ‘normal’ blood pressure?
The ‘normal’ range is determined by looking at the blood pressure in the general population, and the rate of complications occurring above certain blood pressure ranges. This pattern follows a ‘normal’ distribution bell-shaped curve.
The ranges used by the British Hypertension Society (BHS), the European Society of Hypertension and the World Health Organisation (WHO) are:
Systolic (mmHg) Diastolic (mmHg)
Optimal <120 <80
Normal 120-129 80-84
High normal 130-139 85-89
Mild Hypertension (grade 1) 140-159 90-99
Moderate Hypertension (grade 2) 160-179 100-109
Severe Hypertension (grade 3) >180 >110
What are the medical causes of Hypertension?
It is easy to remember some of the common causes by knowing the mnemonic that ‘Hypertension can CREEP up on you without knowing’:
C=Coarctation of the aorta-this is a congenital condition whereby the aorta (largest artery in the body) narrows in the area where it leaves the left side of the heart. It is one of the rarer causes but starts the mnemonic!
R=Renal-this is the commonest cause of high blood pressure because the kidneys are the prime filtering units for blood (they receive 25% of the blood from the heart in each pump cycle). Any damage or scarring to the kidneys can result in hypertension, which is why water infections in children can be serious as they can result in scarring of the kidney and hypertension in later life.
E=Essential (‘primary, cause unknown’).This is a second common group of patients who have high blood pressure without obvious cause. A family history is a hereditable cause. The remainder of the causes (aetiologies) mentioned are referred to as secondary causes of hypertension.
E=Endocrine-Blood pressure can be elevated due to steroid hormones like ‘cortisol’, so conditions such as Cushing’s disease, Conn’s syndrome (a disease of the adrenal glands involving excess production of a hormone, called aldosterone), phaeochromocytoma (tumour of the adrenal glands), or steroids themselves can cause it.
P=Pre-eclampsia is a medical condition in which hypertension arises in pregnancy (pregnancy-induced hypertension) in association with significant amounts of protein in the urine. This is screened for as part of the antenatal screening process. Pre-eclampsia may progress to eclampsia, characterized by the appearance of tonic-clonic seizures
What are the clinical ‘signs’ of hypertension?
‘Signs’ are what the doctor finds on examination, ‘symptoms’ are what the patient experiences, which is why I stated that this condition can go on asymptomatically undiagnosed without medical review.
Kidneys (Renal): A sustained high blood pressure (as previously mentioned) can damage the end organs (such as the kidneys). The doctor may here a ‘bruit’ (‘whooshing’ noise), when auscultating (listening) over them with the stethoscope. They also may find renal function compromised on blood tests and urinalysis.
Heart (Cardiac): The heart can become enlarged (particularly the left ventricle) due to keeping up with the demand of high blood pressure, which can cause the apex (point) of the heart to be displaced when palpating (feeling) for the heart beat. This can be reflected on an X-ray with a large heart shadow, or on an Electrocardiogram (ECG) showing enlarged complexes in the lateral leads (implying strain on the left side of the heart).
Eye disorders (Retinopathies): The blood vessels overlying the retina at the back of the eyes (microvasculature) can also become affected, undergoing grades of change which can be seen using a fundoscope:
Grade 1- the arteries become tortuous with thick shiny walls (otherwise known as ‘copper-wiring’)
Grade 2-nipping of the arteries and veins (narrowing where the arteries cross over the veins)
Grade 3-flame haemorrhages and cotton wool spots
Grade 4-papilloedema (there is a lot of swelling and fluid leaking from the vessels so optic disc loses its clear contours and margins.
What is ‘malignant hypertension’?
‘Malignant hypertension’ is not what the name may imply; it is not related to malignancy (cancer), but it is a serious potentially life threatening condition due to severe uncontrolled blood pressure.
It is a state of severe hypertension (e.g. systolic >200, diastolic>130), whereby the patient may suffer from bleeding from the small vessels (micro vascular) in the eye leading to retinal bleeds (haemorrhages). These patients will often complain of symptoms such as headaches and visual disturbances (i.e. blurring). It requires urgent treatment and can potentially precipitate acute renal failure, heart failure, or encephalopathy (brain damage), which are all hypertensive emergencies in their own right.
In practise, what level of blood pressure reduction should we aim for to avoid complications?
One of the main hypertensive studies looking at complications as a result of high blood pressure was the Framingham Study, conducted in 1948 with 5,209 adult subjects from Framingham, and is now on its third generation of participants. As one of the largest and more respected trials, its cut-off ranges for treating hypertension are used currently in the United Kingdom.
The conclusion was that, otherwise healthy individuals, with a blood pressure (BP) exceeding 140/90 were at a higher risk of developing cardiovascular complications. Patients with evidence of cardiovascular disease (CVD)/renal impairment or diabetes were at a significantly increased risk of developing complications above the range of 130/80.
These are now the target levels used by most general practitioners (GPs) in the UK to decide whether or not to start medical treatment.
A good GP should take into consideration the whole individual, not ‘blindly’ following statistics waiting for a person to develop cardiovascular disease, before deciding whether the above BP cut-off range was too high. Most doctors will calculate a person’s cardiovascular risk as early as possible using a cardiovascular risk calculator. This is another method (based on previous audits and studies), looking at the rate of developing CVD in people in conjunction with predisposing parameters of age, gender, smoking, cholesterol, ethnic preponderance and diabetes. This will enable the doctor to decide whether to start a patient on primary preventative treatment, to minimise risk of a heart attack. For example, the patient could be started on a cholesterol-lowering drug (i.e. a statin), or a blood thinning medication (anti-platelet i.e. low dose aspirin). The doctor should also decide on a target blood pressure range for their patient, or start antihypertensive medication, depending on the patient’s level of risk and current disease status.
Here is an example of the JBS (Joint British Society) CVD risk calculator (you can calculate your own risk, but always consult your doctor if you have any concerns).
It does not however, take into consideration other non-modifiable risk factors (inheritable risks) like family history, which is why it is essential to speak to your doctor about your family history of medical illnesses.
What can I do to reduce my blood pressure without medication?
These lifestyle changes can be the first port of call in reducing blood pressure, and can be adjuvent therapy in managing hypertension.
Some of the methods proven to be effective are:
- Weight loss-a loss of 8.8kg is associated with a fall in blood pressure of 5/7 mmHg.
- Diet- salt reduction (to <5 g per day) and eat a diet rich in fruit, vegetables, and oily fish (low in total and saturated fat). Common sources of salt are nuts, crisps, canned foods and bread. Low salt versions are available.
- Exercise-Brisk walking for 30 minutes a day is as beneficial as more vigorous exercise 3 times a week. Brisk walking for an hour, 3 or 4 times a week may even be better. The mean fall in BP after only 2 weeks of aerobic exercise is 5/4.
- Alcohol-reduce alcohol consumption.
- Stress-This is a risk factor to developing hypertension. However, studies have shown that stress management does not lead to lower blood pressures, thus it is worthwhile being aware that although it is a risk factor, it should not have more emphasis placed on it above the techniques already mentioned.
- Quit Smoking-This obviously increases the CVD risk and is globally detrimental to health in general.
- Contraceptive pill- consider stopping, but not until other adequate contraceptive measures are in place.
- CVD protection medications- Aspirin 75 mg daily if aged >50 years with a CVD risk >20%, end organ damage, or diabetes, and consideration for statin therapy (see your GP).
New updates in hypertension
Recent publication in the medical journal, ‘The Lancet ’, identified, that episodic hypertension, i.e. blood pressures that are incidentally raised on occasions, can be as damaging as persistently raised blood pressure.
This new finding can be implemented in practice by performing 24-hour blood pressure monitoring to capture these episodes. This still has to be taken into context that hypertension should not be diagnosed with a single reading. The doctor should have at least three consecutive high readings over the course of a month to decide whether a patient is prone to hypertension.
Over the last few years, the mercury sphigmomanometers have been abandoned in Europe due to them being a potential hazard in the work place, although many practitioners continue to use them due to their reliable BP readouts.
Hypertension is a common and ‘hidden’ condition in its clinical context. It is potentially life-threatening if left untreated due to end-organ damage.
There are plenty of life-style changes that can alter our modifiable risk factors for the condition. However, this does not substitute the necessity to being checked at regular intervals by your doctor and having your BP measured (which is quick and non-invasive).
There are various antihypertensive medications which can be initiated by your doctor if your condition warrants. They should explain in detail the mechanism of these medications, regarding when to take them, any blood test monitoring required, and potential side effects.
Where can I find more information?
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