The international study, published in The Lancet and involving more than 6700 stroke patients, found that those who received the drug alteplase had a 75 per cent better outcome if they were treated within the first three hours of a stroke. However, the benefit rapidly declined if treatment was delayed by even a few hours.
Study co-author Professor Richard Lindley from University of Sydney, said the study showed that treatment with alteplase significantly increased the odds of a good stroke outcome.
Dissolving blood clots
"Alteplase is effective in dissolving blood clots in those who have suffered a stroke, and is particularly effective if it is administered within three hour," Prof Lindley said.
"Previously alteplase was deemed ineffective and too risky to treat stroke patients who were elderly, diabetic, or had suffered a severe stroke. Doctors were reluctant to use it and these patients were often excluded from treatment.
"However, this study has found that alteplase is an effective emergency treatment for ischaemic stroke patients (strokes caused by blood clots) and should be available irrespective of age, severity, and clinical presentation.
Time critical
"Our data reveals that time is crucial in treating stroke patients - the quicker alteplase is administered, the more effective the treatment.
"This is an important finding considering how disabling a major stroke is for patients, with health outcomes including paralysis, speech impairment, loss of memory and reasoning ability, and coma.
"Prompt treatment with alteplase should be considered for all ischaemic stroke patients as this treatment has the potential to prevent serious disability after stroke.
"This treatment is not without its risks, however the risks are worth the benefits given that stroke is so disabling. Our data revealed that the benefits of alteplase occurred despite an increase in the number of early fatal intracranial hemorrhages of about two per cent.
"This research builds on two earlier papers also published in the Lancet, which found that alteplase was just as effective in older stroke patients as it was in younger patients," Prof Lindley said.
Research funded by the Australian Heart Foundation and NHMRC was included in the data used in this Lancet paper.
Stroke facts
- Stroke is Australia's second biggest killer after coronary heart disease and a leading cause of disability
- A stroke occurs when the blood supply to the brain is restricted, either through a blockage or bleeding. This cuts off the supply of oxygen to the brain causing damage to the affected tissue
- A stroke may cause paralysis, speech impairment, loss of memory and reasoning ability, coma or death
- One in six people will have a stroke in their lifetime
- 65 per cent of those living with stroke also suffer a disability that impedes their ability to carry out daily living activities unassisted
- In 2012 about 50,000 Australians suffered new and recurrent strokes - that is 1000 strokes every week or one stroke every 10 minutes
- In 2012, the total financial costs of stroke in Australia were estimated to be $5 billion
- Not all patients are eligible for alteplase therapy, but rates of treatment of about 20 per cent to 30 per cent are achievable if this research is widely implemented
