Frequently Asked Questions

What is stroke?

A stroke occurs when blood supply to part of the brain is cut off. Blood carries essential nutrients and oxygen to the brain. Without a blood supply, brain cells can be damaged or destroyed and will be unable to perform their function.  For example, if a stroke damages the part of the brain that controls how limbs move, limb movement will be affected. The brain also controls how we think, learn, feel and communicate. A stroke can affect these mental processes. A stroke is sudden and the effects on the body are immediate.  The medical term for stroke is cerebral infarction. An infarct is an area of dead tissue caused by lack of oxygen and blood supply.

What causes a stroke?

There are two main causes of stroke:

Ischaemic Stroke – The most common type of stroke occurs when blood vessels in the brain become narrowed or blocked, cutting off the blood flow to brain cells. This is called an ischaemic stroke. Over 80% of all strokes are ischaemic. This may be caused by:

  • A cerebral thrombosis, when a blood clot (thrombus) forms in an artery going to the brain.
  • Embolic stroke, when a wandering clot, air bubble or fat globule (embolus) is formed elsewhere (usually in the heart or neck arteries) and is carried by the blood stream and clogs a blood vessel in or leading to the brain.
  • A blockage in the tiny blood vessels deep within the brain (lacunar infarct)

Hemorrhagic Stroke – This is caused when a blood vessel bursts causing bleeding (haemorrhage) into the brain. The main causes are:

  • Intracerebral haemorrhage, when a blood vessel bursts within the brain
  • Subarachnoid haemorrhage, when a blood vessel on the surface of the brain bleeds into the area between the brain and the skull (subarachnoid space)

What are the risk factors for stroke?

There are a number of risk factors for stroke.  Preventable diseases that can increase your risk of stroke are as follows:

Hypertension (high blood pressure) – Hypertension is a major risk factor for stroke. Blood pressure by definition is the force of blood pushing against the walls of the arteries. High blood pressure causes the heart to pump harder to move blood through the body. This can weaken blood vessels and damage major organs such as the brain or heart. Left untreated, high blood pressure can lead to stroke.

Atrial Fibrillation (AF) – AF is caused when the two upper chambers of the heart (atria) beat rapidly and unpredictably, producing an irregular heartbeat. AF raises stroke risk as it allows blood to pool in the heart. When blood pools, it tends to clot which can then be carried to the brain, causing stroke.

High Cholesterol – Cholesterol is a fatty substance in the blood that the body can make on its own, but it can also come from fat ingested in foods. High levels of cholesterol in the blood stream can clog arteries and cause a stroke or heart attack.

Diabetes – In people with diabetes, the body either doesn’t produce insulin or the cells ignore the insulin. Without insulin, the body cannot break down sugar which is the basic fuel for the cells in the body. People with diabetes are up to 4 times more likely to have a stroke than someone who does not have the disease, as diabetic patients often have other risk factors associated with stroke.

Carotid Artery Disease – Occurs when the major arteries in the neck become narrowed or blocked. These arteries called the carotid arteries supply your brain with blood so if they become narrowed, less blood and oxygen is supplied to the brain.

Previous stroke, Transient Ischaemic Attack, or a mini stroke – These medical diseases can be controlled and managed even if you have already had issues with any of them in the past. Talk to your doctor.

There are lifestyle risk factors which increase the risks of stroke but that can be changed.  They are:

Smoking – Smoking damages blood vessel walls, speeds up the clogging of arteries, raises blood pressure and make the heart work harder. Smoking doubles your risk of stroke. Second hand smoke (breathing in someone else’s smoke) is also hazardous. Recent research suggests second hand smokers were nearly twice as likely to have a stroke as those who do not live or work in a smoky atmosphere.

Alcohol – A number of studies have suggested that heavy alcohol use, wither habitual daily heavy drinking or binge drinking is related to a higher stroke risk. In addition, cardiac rhythm disturbance, including atrial fibrillation have been observed with heavy alcohol use. It is also linked with high blood pressure. Light or moderate alcohol consumption has been linked to a lower risk of stroke.  The recommended guidelines for alcohol are as follows:

  • No more than 14 units per week for female
  • No more than 21 units per week for male
  • 1 pint = 2 units; 100mls wine = 1 unit

Please note that certain medications and alcohol (particularly Warfarin) can interact. For those who consume alcohol, the recommendation is for no more than 2 drinks per day for a man and no more than 1 drink per day for non-pregnant women.

Obesity and Physical Inactivity – Excess weight puts a strain on the entire circulatory system. Obesity also makes people more likely to develop high blood pressure, high cholesterol and diabetes all of which can further increase stroke risk. Go for a brisk walk, swim, take the stairs and do whatever you can to make life more active. Try to get at least 30 minutes of activity on most or all days.

Drug Abuse – Drugs abuse including cocaine, amphetamines and heroin have been associated with an increased risk of stroke. Stroke caused by drug abuse is often seen in younger people.

Poor Diet – Diets high in saturated fat, trans fats and cholesterol can cause raised blood cholesterol levels. Diets that are high in sodium (salt) can contribute to increased blood pressure. Diets with excess calories can contribute to obesity. A diet containing 5 or more servings of fruit and vegetables per day may reduce the risk of stroke.

There are also a number of risk factors for stroke that cannot be changed. They are:

Age – The risk of stroke rises with age particularly after 55 years

Family History and Race – Your stroke risk is greater if a parent, grandparent, sister or brother had a stroke. African Americans have a higher risk than Caucasians.

Gender – Stroke is more common in men than in women. However women have a higher risk of mortality from stroke than men. Use of birth control pills and pregnancy pose special stroke risks for women.

How do I know if I am having a stroke?

A stroke is a medical emergency and the sooner the person gets help, the more doctors can do to restore the blood flow to the brain and prevent further or permanent damage.  TIME IS BRAIN.

If you have any of the following symptoms, call for an ambulance on 999 or 112 immediately:

  • Sudden weakness or numbness of the face, arm or leg on one side of the body
  • Sudden blurred vision or loss of vision in one or both eyes
  • Sudden slurred speech, loss of speech or difficulty finding words or understanding what others are saying
  • Sudden severe headache
  • Sudden unexplained dizziness, unsteadiness or poor co-ordination especially along with any other symptoms

What is a TIA?

A TIA is a Transient Ischaemic Attack. This is a warning sign of a stroke and is commonly of short duration. This should not be ignored as people who have a TIA have a 33% risk of developing a full blown stroke within 5 years. It is a transient stroke that lasts only a few minutes. It occurs when the blood supply to part of the brain is briefly intercepted causing the area supplied by the brain artery affected to be unable to perform its function (i.e. limb movement), but there is enough blood supply to keep the brain cells alive so that when adequate blood supply is restored, no permanent damage is done.

Symptoms of TIA are the same as that of a stroke but most last for under an hour although they may persist for up to 24 hours. Because there is no way to tell whether symptoms are from acute stroke or a TIA, a person should assume that all stroke-like symptoms are a medical emergency.  Dial 999 or 112.

What are the causes of TIA?

A Transient Ischaemic Attack (TIA) is usually caused by a tiny blood clot that becomes stuck in a small blood vessel artery in the brain. This blocks the blood flow and part of the brain is deprived of oxygen. The affected part of the brain is without oxygen for just a few minutes and soon recovers. This is because the blood clot either breaks up quickly or nearby blood vessels are able to provide necessary blood flow.

How can TIA be managed?

The goal of TIA management is to prevent a future stroke. St. James’s Hospital stroke service operates a daily TIA clinic Monday through Friday from 2pm – 4pm. We will see all patients referred from GP, A&E or self-referrals from patients previously seen by our service by prior appointment. We will try to see all emergency referrals within 24 hours.

Can I take part in research on stroke?

Research is an important component of the Neurovascular Service and patients and their families may be asked to participate in research. Research participation is independent of the clinical assessment. Any research participation is entirely voluntary and subject to patient consent.  You can learn more about our research here.  (INSERT LINK TO RESEARCH PAGE)

Where is the Neurovascular Service located?

The Neurovascular Service is located on the Ground Floor of Mercer’s Institute for Successful Ageing at St. James’s Hospital.  It can be accessed via the Main Hospital Entrance.  Please see the map for directions here.

Is there parking available nearby?

Car parking is limited in the hospital. There is an underground public car park in the middle of the hospital campus that is a 5-10 minute walk to Mercer’s Institute for Successful Ageing.  Follow the signs from the main hospital concourse to MISA.

Can I take public transport to the hospital?

The 123 Bus passes through the grounds of St James’s Hospital and stops close to the main hospital entrance. From the City Centre, the 78A, 51 and 51B stop at the James’s Street entrance. The 19 stops on the South Circular Road close to the Rialto entrance. The red line LUAS also stops in the St. James’s Hospital campus, close to where the Neurovascular Service is situated. Follow signs to Mercer’s Institute for Successful Ageing.  The Neurovascular Service is located on the ground floor.   See additional parking information here.