Blood pressure and stroke

How are high blood pressure and stroke linked?

High blood pressure is the single biggest cause of stroke. When your blood pressure is too high for too long, it can damage your blood vessels, making them narrower, weaker or more likely to burst. This damage can lead to a stroke, which happens when the blood supply to part of your brain is cut off.

Around nine in 10 strokes are preventable. Managing your blood pressure and making healthy lifestyle changes can help prevent a stroke.

Some conditions like atrial fibrillation (an irregular heartbeat) can cause strokes but often don’t have symptoms. Detection is key. A simple pulse check can determine an irregular heartbeat. Treatments and medications can significantly reduce the risk

Types of stroke

There are two main types of strokes, and both are strongly linked to high blood pressure:

Ischaemic stroke (clot)

This is the most common type. It happens when a blood clot blocks a blood vessel leading to the brain. High blood pressure can cause the blood vessels to narrow and harden over time (a condition called atherosclerosis). Fatty material can build up, making it easier for clots to form and block blood flow. This can lead to a stroke or a mini-stroke (also called a TIA – transient ischaemic attack).

​​​​​​​Haemorrhagic stroke (bleed)

This happens when a weakened blood vessel in the brain bursts, causing bleeding in or around the brain. Long-term high blood pressure can make blood vessels weaker and more likely to burst, especially the tiny ones deep inside the brain. These two BSL health clips were made by SignHealth with help and information from the NHS: what is a mini-stroke and treatments for stroke.

​​​​​​​​​​​​​​Small vessel disease and cognitive problems

High blood pressure can also damage the small blood vessels deep in the brain, a condition called small vessel disease. This raises your risk of stroke and can affect your memory, thinking, and decision-making (known as cognitive function).

​​​​​​​​​​​​​​Stroke symptoms – think FAST

A stroke is a medical emergency. Call 999 immediately if you notice any of the following:

F – Face: has one side of their face dropped? Can they smile?
A – Arms: can they raise both arms and keep them there?
S – Speech: is their speech slurred or hard to understand?
T – Time: time to call 999 right away.

Other possible stroke symptoms include:

• sudden severe headache
• confusion
• dizziness or loss of coordination
• problems with speech or understanding
• sudden loss of vision
• weakness or numbness, usually on one side
• trouble swallowing

Real stories: Adam’s experience

Adam had a stroke at 47 and only found out afterwards that he had high blood pressure. Watch his story: Adam’s stroke story – link to video on YouTube

​​​​​​​​​​​​​​​​​​​​​​​​​​​​More information

The Stroke Association Support Helpline is for anyone affected by a stroke, including family, friends and carers. The Helpline can give you information and support on any aspect of stroke. Call on 0303 3033 100, from a textphone 18001 0303 3033 100 or email helpline@stroke.org.uk