Causes and symptoms

WHAT IS A STROKE?

Strokes occur when blood supply to part of the brain is cut off, and cells in that part die.

There are two types of strokes. Ischaemic strokes are caused by blood clots in the brain. Haemorrhagic strokes happen when a blood vessel in the brain bursts, leading to bleeding in the brain.

People can also get what is known as a transient ischaemic attack, when blood supply to part of the brain is temporarily cut off. This causes symptoms similar to those of a stroke, which may last for a few seconds or up to a day.

WHAT CAUSES A STROKE?

Chronic conditions such as high blood pressure and high cholesterol can increase the risk of a stroke.

Diabetics and smokers have a higher stroke risk, as do people with a family history of strokes.

Stress can also increase the chances of suffering from a stroke.

WHAT ARE THE SYMPTOMS?

One of the key signs of a stroke is sudden weakness or numbness, usually on one side of the body.

A stroke victim may also have slurred speech and sudden difficulty in seeing out of one or both eyes. Other symptoms include difficulty swallowing, dizziness, a sudden severe headache, or a sudden loss of consciousness.

WHAT HAPPENS AFTER A STROKE?

Those who have had a stroke typically have problems with moving around or swallowing, and will need rehabilitation.

Up to a third of stroke patients make a full recovery. The remaining two-thirds have some residual disability. Most of the recovery occurs in the first three to six months following a stroke, but may continue slowly for many years.

Linette Lai

Sources: Health Promotion Board, Singapore National Stroke Association, National Neuroscience Institute

A version of this article appeared in the print edition of The Straits Times on May 13, 2016, with the headline 'Causes and symptoms'. Print Edition | Subscribe