Family history of stroke: what it means for your risk

The NHS describes a stroke as blood stopping flowing to a part of the brain. It can affect things like speech and movement, can take a long time to recover from, and is a medical emergency needing urgent help in hospital because it can be life-threatening.

Stroke is one of the main types of cardiovascular disease, which the NHS describes as a group of conditions affecting the heart and blood vessels, often caused by a build-up of fat in the arteries.

In its guidance on cardiovascular disease, which includes stroke, the NHS lists having family members with CVD among the things that may make it more likely that you will get it. The British Heart Foundation likewise says heart and circulatory diseases can run in families, which increases your risk.

The NHS page specifically about the causes of stroke does not single out family history and instead lists a range of other factors. The sources used here do not give a number for how much a relative's stroke raises your own chance, and the size of the effect will depend on the relative's age, how closely related they are and the type of stroke.

A practical way to think about it is that family history is a prompt to check the risk factors you can measure and change, rather than a verdict.

The NHS says a stroke can happen to anyone at any age, but that your risk may increase if you are over 50, are from a Black or South Asian background, have sickle cell disease, have an unhealthy lifestyle, have migraines, take the combined contraceptive pill, are pregnant and have pre-eclampsia, or have just had a baby.

• High blood pressure (hypertension), which the British Heart Foundation links to around half of heart attacks and strokes.

• Diabetes.

• Atrial fibrillation, an irregular and fast heartbeat.

• High cholesterol.

• A previous transient ischaemic attack (TIA, or mini stroke).

For people who have had a stroke or TIA, and more generally for people at risk, the NHS recommends quitting smoking, eating a balanced diet, exercising and cutting down on alcohol, and not forgetting medicines for underlying conditions such as high blood pressure or diabetes.

The NHS notes that if you are at high risk of CVD you may be advised to take a statin, which lowers cholesterol and reduces the chance of CVD. The NHS Health Check, available to people aged 40 to 74, can tell you if you are at higher risk. It is worth telling the person doing your check about any family history of stroke or heart disease.

The NHS says the main symptoms can happen suddenly and are remembered with FAST: face weakness, arm weakness, speech problems and time to call 999. Other signs include weakness or numbness down one side of the body, blurred vision or loss of sight in one or both eyes, difficulty speaking or finding words, confusion and memory loss, dizziness or falling over, a severe headache, and feeling or being sick.

The NHS adds that symptoms can sometimes stop after a short time, so you may think you are fine, but you should still get medical help straight away. Anyone in a family with a history of stroke should know these signs.

Call 999 now if you think you are having, or have had, a stroke, or if you have had signs of a stroke within the last 24 hours even if they have stopped. The NHS says not to drive yourself to A&E. For a TIA the NHS says you still need to be assessed in hospital and referred to a specialist within 24 hours of symptoms starting.