Stroke is the third leading cause of death in the U.S., after heart disease and cancer, with more than 795,000 strokes occurring each year. It affects men more than women and increases with age, so older adults are more likely to have a stroke than younger people.2
Strokes can result in disability or death if they aren’t treated quickly enough. About one-third of stroke survivors have a severe long-term disability, such as paralysis or cognitive problems (memory loss).
At the same time, another third may be partially disabled with less severe disabilities like weakness on one side of their body or difficulty speaking clearly.3 In addition, many survivors require long-term care services that can cost millions of dollars per person over their lifetime.
What Is A Stroke?
A stroke occurs when blood flow to a part of your brain is blocked or interrupted by a clot. This causes brain cells to die, resulting in paralysis, difficulty speaking and understanding, memory loss, and other symptoms. A stroke can happen suddenly — within minutes — or over several hours as smaller clots develop over time.
Strokes are sometimes called “brain attacks” or “cerebral infractions”, but this isn’t accurate because strokes don’t always affect the whole brain at once. The brain has many parts that control different functions, such as movement and speech, vision or balance — so having one part damaged doesn’t necessarily mean that another part will be affected simultaneously.
Why Is Stroke Called The Silent Killer?
They are often referred to as “silent killers” because they occur without warning, and their symptoms may be easily missed by caregivers or others who come into contact with people at risk for stroke. Many stroke symptoms are similar to those of other conditions, so it can be difficult for anyone to know whether something is wrong.
Types Of Stroke
The human brain is a complex organ, but it’s much more than the sum of its parts.
The brain comprises neurons, which are cells that transmit information to other neurons by sending electrical impulses through the body. These cells are organised into networks that carry out different functions — motor control, for example, or vision — in other brain parts.
There are two main types of stroke:
Ischaemic stroke (80%)
Ischaemic stroke is caused by a blood clot forming in the brain, blocking blood flow and starving brain cells of oxygen. It’s more common than hemorrhagic stroke (20%). Ischaemic strokes are also known as thrombotic strokes or embolic strokes. They’re usually caused by a plaque made up of cholesterol, fat and other substances building up within your artery walls.
Hemorrhagic stroke (20%)
A hemorrhagic stroke happens when an artery in the brain leaks blood or ruptures (breaks open). The leaked blood puts too much pressure on brain cells, damaging them.
High blood pressure and aneurysms—balloon-like bulges in an artery that can stretch and burst—are examples of conditions that can cause a hemorrhagic stroke. It is caused by bleeding within an artery supplying blood to your brain – usually due to thinning of the walls.
Transient ischemic attack (TIA or “mini-stroke”)
TIAs are sometimes known as “warning strokes.” It is important to know that
- A TIA is a warning sign of a future stroke.
- A TIA is a medical emergency, just like a major stroke.
- Strokes and TIAs require emergency care. Call 9-1-1 if you feel signs of a stroke or see symptoms in someone around you.
- There is no way to know in the beginning whether symptoms are from a TIA or a major type of stroke.
- Like ischemic strokes, blood clots often cause TIAs.
- More than a third of people who have a TIA and don’t get treatment have a major stroke within one year. As many as 10% to 15% of people will have a major stroke within three months of a TIA.
Warning Signs Of A stroke
Recognising the warning signs can mean the difference between life and death. The American Stroke Association says that about 80 per cent of people who have a stroke are not aware it is happening, which means they don’t get help quickly enough.
The warning signs include:
- Sudden numbness, tingles or weakness of the face, arm or leg — especially on one side of the body
- Sudden confusion, trouble speaking or understanding speech
- Sudden trouble seeing in one or both eyes
- Sudden trouble walking, dizziness, loss of balance or coordination
- Sudden severe headache most ties without a known cause.
Risk Factors And Causes
The main risk factors include:
- Age
Strokes are more common as you get older; they are most likely to occur after age 55
- High blood pressure (hypertension)
This increases your risk because high blood pressure can damage arteries that carry blood through your body. A person whose systolic pressure is 140 mm Hg or higher or whose diastolic pressure is 90 mm Hg or higher has an increased risk of stroke.
- Heart disease
Heart disease can lead to narrowed arteries, increasing your risk of stroke.
- Smoking
Smoking damages your heart and lungs, making it harder for them to pump blood efficiently.
- Cholesterol
A high LDL cholesterol level significantly raises the risk of heart attack and stroke.
- Diabetes
If you have diabetes, you’re at greater risk of complications from a stroke than someone without the disease. The longer you’ve had diabetes, the greater your chance of stroke. If you have diabetes and high blood pressure, you have an even higher risk of stroke than someone with just one condition.
- Alcohol abuse
Drinking too much alcohol can damage your heart muscle and increase your blood pressure, increasing your heart attack or stroke risk.
- Atherosclerosis (hardening of the arteries)
Atherosclerosis is a disease in which fatty substances and other materials form plaques (deposits) on the inner walls of arteries. These deposits are cholesterol, calcium, other fats, and cell waste.
These deposits narrow the arteries and make them more likely to form a blood clot. Plaque can break off and cause clots to travel to other body parts. Atherosclerosis causes most heart attacks and strokes by blocking blood vessels that supply oxygen-rich blood to your heart muscle or brain.
If your heart muscle doesn’t get enough oxygen-rich blood, it cannot pump properly and starts to die. This can cause chest pain (angina) or an abnormal heartbeat (arrhythmia). If a clot forms, it can completely block off blood flow to the part of your brain where it is lodged — causing a stroke.
- Atrial fibrillation or other irregular heartbeats
Atrial fibrillation is one of the most common cardiac arrhythmias or irregular heartbeats. It causes the heart’s upper chambers to quiver instead of beating normally. This can lead to blood pooling and clotting in the atria and then be carried into the veins that return blood to the heart. If a clot breaks free from these clogged veins, it can cause a stroke.
How To Prevent Stroke
The good news is that stroke is preventable. Here are some ways you can help prevent a stroke:
- Know your risk factors.
The risk factors include high blood pressure, high cholesterol, diabetes, smoking, heart disease and atrial fibrillation (an abnormal heart rhythm). If you have one or more of these conditions, talk with your doctor about ways to reduce the risk of a brain shock.
- Don’t smoke — or quit if you do.
Smoking increases the risk of having a stroke by two-thirds compared with people who don’t smoke. If you’re a smoker, talk with your doctor about finding the proper treatment for quitting to live longer and healthier.
- Exercise regularly.
Regular exercise can lower blood pressure and decrease your chances of developing high cholesterol or diabetes. Talk with your doctor about starting an exercise program that’s right for you.
- Control stress in your life.
Stress can increase blood pressure and decrease the amount of oxygen getting to the brain, putting you at risk. Find ways to reduce stress in your life to not interfere with your blood pressure.
- Eating a healthy diet.
A diet rich in fruits, vegetables, and whole grains can help lower your risk of high blood pressure and high cholesterol.
In summary, strokes are more common than most people think, and they can happen to anyone. Fortunately, they are preventable (or at least more likely to be preventable) if we care for our physical and mental health. The hope is that people will be more inclined to help themselves better by raising awareness.
