System to aid forecast of patient stroke risk

PUBLISHED : Wednesday, 11 February, 2009, 12:00am
UPDATED : Wednesday, 11 February, 2009, 12:00am

A new scoring system can more accurately predict the risk of stroke and death for patients who have previously suffered a mini stroke, according to the Chinese University of Hong Kong.

Mini stroke, or transient ischaemic attack (TIA), is a mild form of stroke during which the brain receives insufficient blood supply, resulting in a loss of brain function that lasts for less than 24 hours.

However, between 15 and 26 per cent of TIA patients later suffer a severe stroke, while about 3,000 patients die of all categories of stroke in Hong Kong each year, according to neurologist Yannie Soo Oi-yan of the university's department of medicine and therapeutics.

A scoring system called ABCD{+2} assesses the risk of severe stroke and death within 90 days after a patient has suffered a mini stroke.

Under the system, higher scores, and therefore a higher likelihood of death, are given to older patients with diabetes, high blood pressure and other ailments.

But Dr Soo said the westerndeveloped system was not tailor-made for Chinese patients.

In Hong Kong and the mainland, about 30 to 50 per cent cases of stroke result from a hardening of arteries in the head, while this contributes to less than 10 per cent of cases in the west, she said.

As a result, the university modified the ABCD{+2} system to include a computerised axial tomography (Cat) scan of the brain and an ultrasound scan of arteries in the head.

Dr Soo said the new system, ABCD{+2}L{+2}, was more accurate for Chinese patients and could predict the risk for up to 40 months.

'Although TIA is brief and only lasts for less than 24 hours, the risk is not low at all. One out of 10 patients could die as a result,' Dr Soo said.

She said the Cat scan and the ultrasound test were simple and could be done within 45 minutes.

Stroke is the third most common cause of death worldwide and the leading cause of disability in adults. Symptoms include sudden onset of slurred speech, and weakness or numbness on one side of the body.

Dr Soo urged patients aged over 60 and those with high blood pressure and diabetes to pay extra attention, and said the best way to prevent stroke was to have regular exercise, a balanced diet and to quit smoking.

Silent killer

Stroke is the third most common cause of death worldwide

The number of Hongkongers who die of strokes each is year about: 3,000