Health Information



What is Stroke?

The medical term of stroke is "cerebral vascular disease". It occurs when blood supply to the brain is reduced or blocked for certain reasons leading to a sudden lack of oxygen in the brain cells. In a few minutes, the brain cells may be damaged and lose their functions. As a result, it affects the body functions controlled by that part of brain cells.


Stroke is a serious medical emergency. About 30% of the sufferers die in three months’ time. However, more than 50% of the survivors can fully resume self-care ability and less than 20% suffer from severe disability. The factors affecting recovery depend on the severity of brain damage (including the type of stroke and the area and site affected), the complications developed and the self-care ability of the patient before the stroke. Besides, the attitude of patients and the support from their families/carers as well as the appropriate rehabilitation treatments may also have decisive effects.


Stroke is mainly divided into two types:

Ischemic stroke

It is caused by cerebral thrombosis (a blood clot forms inside the vessels of the brain) and is relatively common, more than 70% of strokes belong to this type.  Also cerebral atherosclerosis causes formation of blood clot in the cerebral artery or the blood clots can be formed with the hearts or carotid artery in the neck. The clot can travel up to the cerebral vessels distally and block the flow of blood. Those cardiac diseases including arrhythmia (abnormal heart rate), cardiac valve problems and coronary heart disease could cause the stroke.


Hemorrhagic stroke

It is caused by the bursting of a blood vessel inside the brain.  Most often, it is associated with persistent high blood pressure. There are also cases in which a blood vessel on the surface of the brain tissue bursts. This is associated with congenital cerebral vascular diseases. The blood would be released below the arachnoid space (the space between the brain tissue and the skull) pressing the brain tissue.  Moreover, the blood vessel will constrict after bleeding, further reducing the flow of blood.

Both ischemia (inadequate flow of blood to a part of the body, caused by blockage of the blood vessels) and bleeding may prevent the brain tissue from receiving adequate nutrition and oxygen. The affected neurons will therefore die, giving rise to various neurologic symptoms. The causes of Transient ischemic attack (TIA) are similar to those of Ischemic stroke.


How to prevent Stroke?

To prevent stroke, the most important aspect is to prevent the development of vascular atherosclerosis (blood vessel hardening). You may take following precautions to prevent stroke:


Controlling high blood pressure

  1. Lifestyle modification: Reducing sodium taken from diet, adhering to the "low-sodium, low-sugar, low-fat, high-fiber" dietary principle, controlling weight, taking exercise regularly and avoid addicted to alcohol
  2. Medication: taking medicine according to doctor's instructions
  3. Quit smoking immediately
  4. Controlling diabetes mellitus
  5. Lowering cholesterol: through diet and exercise, where necessary, taking medicine according to doctor's instructions
  6. Handling pressure and learning to relax




(Source: Hospital Authority Smart Patient)