High blood pressure has been called “the silent killer” because it usually has no symptoms, yet damage to vital organs occurs progressively over time.  Some people may only discover they have hypertension, or high blood pressure, when they experience a major health crisis because of it, such as a heart attack or stroke.

This is why getting one’s blood pressure checked regularly is so important, even for those who seem and feel quite healthy.

Some common complications of uncontrolled high blood pressure:

Damage to the blood vessels

High blood pressure is associated with arteriosclerosis and atherosclerosis (often used interchangeably): the hardening and narrowing/blockage of the arteries. When blockages occur in the arteries that supply blood to the heart muscle itself (the coronary arteries), this is called coronary artery disease – the main cause of heart attack.

Hypertension contributes to the development of coronary artery disease, because high blood pressure exerts added force against the artery walls. Over time, this can damage the arteries, making them more vulnerable to narrowing. The hardened artery surface can also encourage the formation of blood clots.

Peripheral vascular disease (damage to blood vessels outside of the heart, especially those in the legs) may cause cramps on walking and may even lead to amputation because of lack of blood.

Hypertension is also a major risk factor for abdominal aortic aneurysm: when the large blood vessel (aorta) that supplies blood to the abdomen, pelvis and legs becomes abnormally large or forms a bulge.

Damage to the heart

If you have hypertension, your heart works harder than it should to pump blood to the body’s tissues and organs. If this pressure isn't controlled, your heart can enlarge and weaken as your arteries become scarred, hardened and inflexible. Eventually, your overworked heart may not be able to pump and transport blood properly through your stiff arteries.

These changes increase the risk of heart disease and consequently heart attacks (the death of heart muscle because of not receiving sufficient blood and oxygen) and heart failure (failure to pump enough blood to the body’s tissues and organs to meet their needs), but also have a damaging effect on your arteries, brain, eyes and kidneys.

Damage to the brain

People with hypertension are at much greater risk for both kinds of stroke. An ischaemic stroke occurs when blood flow to an area in the brain is cut off, usually because of a blocked artery.  A haemorrhagic stroke occurs when a weakened blood vessel ruptures, and there is bleeding into the brain.

Increasingly doctors are also recognising the association between hypertension and dementia, and that adequate treatment can delay or prevent some forms.

Damage to the kidneys

The kidneys play a vital role, removing toxins and helping to control fluid levels. Consistently elevated blood pressure can damage the arteries leading to the kidneys ? they become thickened and narrowed. This reduces the oxygen supply to the kidneys. It also reduces the amount of blood brought to the kidneys for filtering.

Hypertension is a major cause of kidney disease and ultimately kidney failure. Both hypertension and kidney failure can be silent diseases without any warning symptoms.

Damage to the eyes

Uncontrolled hypertension can damage blood vessels that supply blood to the retina (the light-sensitive lining of the back of the eye), a condition called retinopathy. It can lead to vision loss or blindness if it remains untreated.

Erectile dysfunction

As with the other complications mentioned, high blood pressure is associated with widespread arterial disease. Small arteries tend to be affected first, but this may go unnoticed, except in the penile arteries. Here, decrease in blood supply can cause erectile dysfunction, ED. Today it is recognised that ED is an early sign of arterial disease and should therefore be treated without delay.


Hypertension is a risk factor for the development and worsening of many diabetes complications. Likewise, having diabetes increases your risk of developing high blood pressure.

Want more info? Read "How to Reduce Your Risk of Hypertension."

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