A stroke (or a cerebrovascular event) is a disease caused by disruption of blood supply to the brain.
It results either from a stoppage of blood supply to a part of the brain due to a blockage in the vessels carrying oxygen and nutrients to the brain usually due to a clot (ischaemic stroke), or from the rupturing of these blood vessels (haemorrhagic stroke).
When that happens, the part of the brain cannot get the blood (and oxygen) it needs, so brain cells die. Ischaemic strokes are more common than haemorrhagic strokes. A transient ischaemic attack (TIA) or a mini-stroke refers to a stroke that resolves within 24 hours, often with full recovery.
Stroke is a major health problem as it is the second leading cause of death and the third leading cause of disability all over the world. According to the World Health Organization, 15 million people suffer stroke worldwide each year. Of these, 5 million people die and another 5 million are permanently disabled.
Nearly three-quarters of all strokes occur in people over the age of 65 and the risk of having a stroke more than doubles each decade after the age of 55.
What causes a stroke?
Uncontrolled blood pressure (hypertension) is the commonest cause of stroke around the world in all age groups. Africa bears the greatest burden of hypertension, which is the strongest and most common modifiable risk factor for stroke.
The following are factors that may increase one’s chances of developing a stroke:
- Having diabetes mellitus
- Having heart disease or condition (E.g. Atrial fibrillation, heart attack)
- Having a peripheral arterial disease
- A previous stroke or mini-stroke post-tia (TIAs are associated with a high early risk of stroke)
- Combined oral contraceptive pill
- Having excess lipids or fats in the body
- Excess alcohol intake
- Having a clotting disorder
- Obesity and/or physical inactivity
- Illegal drug use (E.g. Cocaine use)
What are the signs and symptoms seen when someone is having a stroke?
Typically, a stroke develops suddenly over a few minutes or hours. Symptoms are a consequence of the areas of the brain affected. For example, if the area of the brain starved of blood supply is the area responsible for speech, the person becomes unable to speak. Generally, the following are common symptoms of a stroke:
- Inability to move parts of the body usually on one side. The arms and legs become floppy.
- Inability to stand upright or see in one or both eyes.
- Sudden severe headache.
- Face distortion or droopiness when attempting to smile.
- Sudden inability to speak or understand speech.
How can a diagnosis of a stroke be made?
Doctors can tell that one has had a stroke based on the development of the condition and the symptoms seen. To offer prompt life-saving care, blood tests and scans are required.
A computed tomography scan (CT Scan) tells your doctor what type of stroke it is and the areas affected. This influences the modes of treatment as well as the likely course of the stroke.
Other investigations may be required based on the peculiarities of the particular individual. Strokes caused by a rupture of a blood vessel are typically more serious than those caused by a blockage in a blood vessel.
How is a stroke treated?
Identifying a stroke and alerting others and offering first aid is very important. At the hospital, immediate resuscitation is offered before a definitive procedure is done.
Usually, clot-dissolving medications are given for ischemic strokes while hemorrhagic strokes often require surgery. This may, however, change based on the particular individual and other circumstances.
How Can You Prevent A Stroke?
Effective prevention strategies in preventing a stroke (or a recurrence of a stroke) include the following:
- Addressing current health concerns. If you have hypertension, elevated lipids and diabetes, use medications as prescribed and go for routine follow-up visits as scheduled.
- Quit smoking.
- Limit alcohol intake.
- Get active. Exercising for around 30 minutes daily or 150 minutes weekly for good health and wellness.
- Choose healthier diets with more fruits and vegetables.
These steps when used in combination have proved effective in reducing the frequency of occurrence of stroke.