swosn@lhsc.on.ca 519-685-8500 ext. 32462

General Information About Stroke

Up to 80% of strokes are preventable and most of the conditions that can increase your chance of having a stroke are within your control. Read on to learn more about stroke and TIA, their risk factors, and what you can do to help lower your risk of stroke.


A stroke occurs when the blood supply to part of the brain is interrupted. Without oxygen-rich blood, brain cells begin to die. If the blood supply is not restored, the affected part of the brain dies, causing disability or death.

Why is Stroke an Emergency?

Your brain controls everything in your body. The longer the blood supply is cut off the more brain cells might die. Call 911, or your local emergency number, right away to get help fast if you experience the signs of stroke. Doctors can give you a clot-busting drug to help restore blood flow to your brain, but this medicine must be given soon after the stroke. Don’t wait. Call 911.

A transient ischemic attack (TIA) is a “mini-stroke”. Like a stroke, it hits suddenly and without warning. TIAs last a few minutes or up to 24 Hours. The difference between a stroke and a TIA is that with a TIA the symptoms go away within a short period of time.

Why is TIA an emergency?

A TIA is serious warning sign that you may later have a stroke. TIA and stroke share the same warning signs. Don’t wait to see if the symptoms go away. Don’t try to figure out on your own what’s causing them. Call 911. Even if the symptoms go away it’s important that the doctor quickly find out what caused these symptoms. This will help prevent a future stroke

Stroke and TIA have the same warning signs. If you experience any of these warning signs it’s important to call 911 right away. Don’t drive yourself to the hospital because you don’t know if the symptoms will get worse. Don’t wait. It’s important to act F.A.S.T.:

FAST English

There are a conditions that can increase your risk of stroke. Some of them are outside of your control, such as increasing age, different cultural backgrounds, or if you (or an immediate family member) have already had a stroke or TIA.

The good news is that most risk factors are within your control:

  • Undiagnosed or uncontrolled high blood pressure (hypertension): This key risk factor can’t be “felt” so many people don’t know they have it. When treated and controlled, the risk of stroke drops.
  • Undiagnosed or untreated irregular heartbeat (atrial fibrillation): This condition could lead to blood clots forming in the heart which can break off, interrupt blood flow to the brain and cause a stroke.
  • Smoking: Smoking and second hand smoke both lead to high blood pressure and plugged arteries. Your risk of stroke is even higher if you smoke and take the birth control pill or smoke and get migraine headaches.
  • Poor diet: Diets high in fat, sugar, processed or salty foods increase the risk of high blood pressure, weight gain and diabetes.
  • Lack of exercise: This may result in an increased risk for high blood pressure, diabetes, weight gain and high stress levels.
  • Waist circumference greater than 88cm for women and 102cm for men: As waist size increases so does stroke risk. Excess weight can lead to high blood pressure, high cholesterol and diabetes.
  • Alcohol consumption: Having more than 2 drinks per day (to a maximum of 10 drinks a week for women/15 drinks a week for men) increases the risk of stroke.
  • Diabetes, especially if uncontrolled: High blood sugar levels damage the arteries and could lead to high blood pressure.
  • High cholesterol: This is the fat in your blood. High levels of cholesterol lead to the buildup of fat (plaque) on artery walls, narrowing the path for blood to flow and increasing stroke risk.
  • Recreational (Street) Drug Use: Drugs including cocaine, amphetamines, ecstasy, heroin/opioids, PCP, LSD, and cannabis/marijuana are linked stroke. They cause reactions in the body that can increase the risk of stroke in the short-term and long-term.
  • Birth Control or Hormone Replacement Therapy: These medications can increase your risk of stroke when they contain estrogen. Speak to your healthcare provider about your best options.
  • Stress: High stress levels are linked with unhealthy lifestyle patterns (increased alcohol use, unhealthy diet, etc). Stress can also lead to high blood pressure, obesity, anxiety and depression.

The Heart and Stroke Foundation of Canada has a page dedicated to stroke, which covers a full range of information including:

  • Information on stroke an stroke warning signs
  • Stroke risk factors and strategies for managing or reducing them
  • Stroke Recovery
  • Publications

Visit the Heart and Stroke Foundations’s Web Page on Stroke