What is a transient ischaemic attack (TIA)?

A transient ischaemic attack (TIA), also known as ‘mini stroke’ or ‘silent stroke’, is caused by a brief interruption in blood supply to the brain as the result of a blood clot.

This can cause stroke-like symptoms, but they are short-lived – usually between a few minutes and a few hours – and typically go within 24 hours.

The main signs and symptoms of a TIA

The main symptoms of a TIA can be remembered with the word FAST:

• Face: the face may have dropped on one side; the person may not be able to smile, or their mouth or eye may have dropped
• Arms: the person may not be able to lift both arms and keep them raised because of weakness or numbness in one arm
• Speech: the person’s speech may be slurred or garbled, or they may not be able to talk at all, despite appearing to be awake. They may also have problems understanding what you’re saying to them
• Time: it’s time to call 999 immediately if you see any of these signs or symptoms

Other symptoms of a TIA:

• weakness/numbness of one side of the body
• sudden changes in vision, such as blurred or loss of vision
• sudden headache
• confusion
• dizziness
• vertigo
• being sick
• difficulty understanding what others are saying
• problems with balance and coordination
• difficulty swallowing (dysphagia)

The link between TIAs and dementia

Having a TIA can increase your risk of developing dementia, especially vascular dementia. Having a single TIA does not usually cause dementia, but having repeated TIAs over time can lead to vascular dementia. This is because they cause small but widespread damage to the brain.

People living with other types of dementia may also be at risk of a TIA or stroke, so if you notice symptoms, it’s important to seek medical advice and treatment.

Many of the risk factors for TIAs and dementia are similar, including high blood pressure, smoking, a poor diet and a lack of exercise, so if you have lifestyle factors that increase the risk of TIAs, you may also be at a greater risk of developing dementia.

TIAs can also cause a progression of dementia symptoms.

Can a TIA bring on dementia?

People who have experienced multiple TIAs are at greater risk of developing vascular dementia, although a single TIA is unlikely to trigger the condition. You can reduce the risk by taking any medication you are prescribed according to the instructions, maintaining a healthy blood pressure, not smoking, keeping alcohol consumption within the recommended limits, avoiding stress, staying active and eating a healthy, balanced diet.

What to do if you have concerns

It can be difficult to know whether you’re having a TIA or a stroke, so if you notice any possible signs in yourself or someone else, it is important to call 999 immediately and explain your symptoms. Don’t ignore them, even if they disappear quickly.

If you have a suspected TIA you should be seen in hospital, where your symptoms will be assessed. This may include a brain scan. Depending on the outcome of the assessments, you may be referred to a TIA or stroke clinic.

A TIA can be a warning sign that you may be at risk of having a stroke, so doctors can advise how to reduce this risk with medication and investigations.

If you suspect you may have had a TIA in the past but didn’t seek treatment, make an urgent appointment with your GP. They may refer you for a hospital assessment.

People who experience a TIA are at increased risk of developing depression. Seek advice from your GP if you have concerns about your mood after experiencing a TIA.

Reducing the risk of a TIA

There are steps that you can take to reduce your risk of TIA:

• Follow a healthy diet including at least five portions of fruit and vegetables a day
• Limit the amount of salt and processed foods in your diet
• If you smoke, make every effort to stop – your GP can offer advice
• Take regular exercise: a total of 150 minutes across the week is recommended for most people
• Keep your alcohol intake within the recommended guidelines (14 units per week)
• Take steps to reduce stress
• Take any medication as prescribed
• Make sure you manage health conditions such as atrial fibrillation, high blood pressure, high cholesterol and diabetes by taking any medication you are given and attending regular reviews

Driving after a TIA

If you drive a car or motorbike, you must stop driving for at least one month after a TIA or stroke and can only restart only when your doctor or healthcare professional tells you it is safe.

You do not need to tell the Driver and Vehicle Licensing Agency (DVLA) if you have had a TIA and recovered, but you do need to tell them if, after one month, you are still experiencing:

• weakness in your arms or legs
• vision problems related to the TIA
• problems with balance, memory or understanding

You must also tell the DVLA if:

• you have had any type of seizure
• you needed brain surgery
• your doctor thinks it is unsafe for you to drive

If you drive a bus, coach or lorry, you do have to notify the DVLA if you have had a TIA or stroke, and you must stop driving them for at least a year.

GOV.UK has more information about telling the DVLA about a medical condition or disability. In Nothern Ireland, visit Driving after stroke, cerebral thrombosis, amaurosis (nidirect).

If you have dementia, you are legally obliged to tell the DVLA/DVA about your diagnosis.