Stroke is a “brain attack” which occurs when blood flow to an area of brain is cut off. When this occurs, brain cells begin to die because they are deprived of oxygen.
When brain cells die during a stroke, activities controlled by that part of the brain are lost. For example, memory and muscle control are lost.
Stroke is often referred to as a “brainattack” to denote the fact that it is caused by a lack of blood supply to the brain, very much like a heart attack is caused by a lack of blood supply to the heart.
The term “brain attack” also conveys a more urgent call for immediate action and emergency treatment by the general public.
Age has an influence on the risk for stroke. After the age of 30 years, the risk of stroke rises steeply globally. Ninety-five percent of all strokes occur in people aged over 65 years.
The risk of dying due to stroke also rises with age. Similarly the chance of recovering fully from paralysis and disability caused by stroke also diminish with age. Therefore, the chance of recovering fully from paralysis and disability is very low in aged individuals who have a stroke.
Males are more at risk of stroke than females.
A hemorrhagic stroke occurs when the blood vessels in the brain breaks, or ruptures causing the blood to spill into the surrounding tissues.
Types of Hemorrhagic Strokes
There are two types of haemorrhagic strokes:
(i) Aneurysm: This causes a portion of the weakened blood vessel to balloon outward and sometimes rupture.
(ii) Arteriovenous , this involves abnormally formed blood vessels. If such a blood vessel ruptures, it can cause a haemorrhagic stroke.
2. Transient ischemic attack
This is also known as a warning or ministroke.
It is caused a clot which temporarily blocks blood flow to the brain.
The blood clot and TIA symptoms last for a short period of time.
3. Ischemic stroke:
This happens when a blood clot stops blood from flowing to your brain.
The blood clot is often due to *Atherosclerosis*
Atheriosclerosis is a buildup of fatty deposits on the inner lining of a blood vessel.
A portion of these fatty deposits can break off and block blood flow in the brain. This event is similar to that of a heart attack, which occurs where a blood clot blocks blood flow to a portion of the heart.
Ischemic stroke can be embolic. This means that blood clot travels from another part of the body to the brain.
Sometimes, Embolic strokes occur due to a condition called *Atrial fibrillation* , this causes irregularly beating of the heart.
*Thrombotic stroke* is an ischemic stroke which occurs when a clot forming in a blood vessel in the brain.
What are the risk factors of stroke?
Generally, the most common risk factors for stroke are:
(i) High blood pressure,
(ii) High cholesterol,
(iv) Diabetes, and
What are the symptoms of stroke?
**Numbness of one half or part of the body.
**Acute onset of weakness or paralysis of half or part of the body.
**Acute change in level of consciousness or confusion.
**Speaking or understanding speech.
**Difficulty with balance and vertigo.
What are the causes Of Stroke?
There are different causes of stroke based on the types.
Causes of ischemic stroke
Ischemic stroke is caused by the blockages or narrowing of the arteries that provide blood to the brain, resulting in ischemia. *ischemia** is a severely reduced blood flow that damages brain cells.
These blockages are sometimes caused by blood clots, that can form either in the arteries within the brain, or in other blood vessels in the body before being swept through the bloodstream and into narrower arteries within the brain.
Fatty deposits within the arteries called plaque can cause clots that result in ischemia.
Causes of hemorrhagic stroke
Hemorrhagic strokes are caused by arteries in the brain which can be either leaking blood or bursting open.
The brain cells are pressurised by the leaked blood and caused the brain cells to damage.
It also reduces the blood supply reaching the brain tissue after the hemorrhage point.
Blood vessels can burst and spill blood within the brain or near the surface of the brain, sending blood into the space between the brain and the skull.
The ruptures can be caused by conditions such as hypertension, trauma, blood-thinning medications, and aneurysms (weaknesses in blood vessel walls).
Intracerebral hemorrhage is the type of hemorrhagic stroke which occurs when brain tissue is flooded with blood after an artery in the brain bursts.
Causes of transient ischemic attack (TIA)
TIAs are not the same as the kinds above. The reason is because the flow of blood to the brain is only briefly interrupted. TIAs are look like ischemic strokes because they are mostly caused by blood clots or other clots.
TIAs should be regarded as medical emergencies just like the other kinds of stroke, even when the blockage of the artery and symptoms are not permanent.
They serve as warning signs for future strokes and shows that there is a partially blocked artery or clot source in the heart.
How can you prevent Stroke?
The best way to prevent stroke is to address the underlying causes.
This is best done by living healthy life style, which include the following:
(i) Eating a healthy diet.
(ii) Maintaining a healthy weight.
(iii) Exercise regularly.
(iv) Avoid smoking.
(V) Avoid Alcohol or drink moderately (if you must drink)
(Vi) Eating plenty of fruits, vegetables, and healthy whole grains, nuts, seeds, and legumes.
(Vii) Eating little or no red or processed meat.
(Viii) Reduce intake of cholesterol and saturated fat.
(ix) Reduce salt intake to support healthy blood pressure.