Using aspirin urgently could substantially reduce the risk of major strokes in patients who have minor ‘warning’ events, a group of European researchers has found.
Writing in The Lancet, the team say that immediate self-treatment when patients experience stroke-like symptoms would considerably reduce the risk of major stroke over the next few days.
Aspirin is already given to people who have had a stroke or transient ischaemic attack (TIA – often called a ‘mini-stroke’) to prevent further strokes after they have been assessed in hospital and in the longer-term, reducing the subsequent stroke risk by about 15 per cent.
However, based on a previous study in Oxford (the EXPRESS Study) the team suspected that the benefits of more immediate treatment with aspirin could be much greater.
Lead researcher Professor Peter Rothwell, a stroke expert from the University of Oxford, explained, ‘The risk of a major stroke is very high immediately after a TIA or a minor stroke (about 1,000 times higher than the background rate), but only for a few days. We showed previously in the EXPRESS Study that urgent medical treatment with a ‘cocktail’ of different drugs could reduce the one-week risk of stroke from about 10 per cent to about two per cent, but we didn’t know which component of the ‘cocktail’ was most important.
‘One of the treatments that we used was aspirin, but we know from other trials that the long-term benefit of aspirin in preventing a stroke is relatively modest. We suspected that the early benefit might be much greater. If so, taking aspirin as soon as possible after warning symptoms could be very worthwhile.’
The team therefore revisited the individual patient data from 12 trials (about 16,000 people) of aspirin for long-term secondary prevention – that is, to prevent a further stroke – and data on about 40,000 people from three trials of aspirin in treatment of acute stroke.
They found that almost all of the benefit of aspirin in reducing the risk of another stroke was in the first few weeks, and that aspirin also reduced the severity of these early strokes. Rather than the 15 per cent overall reduction in longer-term risk reported previously in these trials, aspirin reduced the early risk of a fatal or disabling stroke by about 70 to 80 per cent over the first few days and weeks.
Professor Rothwell said, ‘Our findings confirm the effectiveness of urgent treatment after TIA and minor stroke – and show that aspirin is the most important component. Immediate treatment with aspirin can substantially reduce the risk and severity of early recurrent stroke. This finding has implications for doctors, who should give aspirin immediately if a TIA or minor stroke is suspected, rather than waiting for specialist assessment and investigations.’
