Both transient ischemic attacks and minor strokes only last a few hours and rarely have any enduring effects. But they can lead to a major stroke, which is much more dangerous and may impact an individual's health more severely. "How can this best be prevented?" researchers ask.
This major organ becomes starved of oxygen, which might lead to trouble speaking, visual disturbances, and numbness in the body's extremities.
A minor stroke is similar, but it is normally taken to have a more persistent impact, and the term "is often used for stroke patients with mild and nondisabling symptoms."
However, unlike a major stroke, TIAs do not tend to cause serious, lasting damage. Still, many who experience a mini-stroke may go on to experience a major stroke within the next 90 days, with more serious consequences.
To avoid this, people who have had a TIA should receive immediate medical attention — within 3 hours from the event — and they may be prescribed an anticoagulant drug to prevent further blockages that may obstruct the circulation of blood to the brain.
But researchers are now asking if there are even more effective preventive methods to keep major stroke at bay after a TIA or minor stroke.
Clay Johnston, a professor of neurology at Dell Medical School in the University of Texas at Austin, suggests that patients taking an anticoagulant and aspirin combo might reduce their risk of experiencing a major stroke even further.
In a new study — the results of which were published in The New England Journal of Medicine — Prof. Johnston and team suggest that taking the anticoagulant clopidogrel, as well as aspirin, can lower an individual's risk of major stroke post-TIA.
Drug combination shows promise
The researchers analyzed medical data sourced from 4,881 adults across 10 countries who had had a TIA or a minor stroke. Specifically, they were interested in evaluating the outcomes for those patients who had been administered both clopidogrel and aspirin.
They found that this aspirin plus anticoagulant combo resulted in a 25 percent lower risk for experiencing a major stroke, heart attack, or death caused by the formation of blood clots within 3 months from the initial event.
Yet this approach does not come without specific risks of its own. Thus, "The study gives [...] solid evidence that we can use this drug combination to prevent strokes in the highest-risk people, but not without some risk of bleeding," notes Prof. Johnston.
The participants who took both aspirin and clopidogrel rather than just aspirin after a TIA or minor stroke had an increased risk of hemorrhage. Therefore, for every thousand patients receiving this drug combo, five extra major bleeding events would be expected, as well as 15 fewer strokes and major ischemic events.
The researchers note that, despite the heightened possibility that a hemorrhage might occur, the benefits of the clopidogrel-aspirin treatment far outweigh the risks, as bleeding is normally reversible and therefore easier to attend to.
Treatment benefits outweigh the risks
"Of the 33 major hemorrhages that occurred in these 4,881 patients," explains study co-author Dr. J. Donald Easton, from the University of California, San Francisco School of Medicine, "more than half involved the gastrointestinal tract, and none of them [were] fatal."
"These largely preventable or treatable bleeding complications of the treatment," he adds, "have to be balanced against the benefit of avoiding disabling strokes."
A trial that had already tested the waters with the clopidogrel-aspirin combination had also pointed out its benefits, but it had not spotted the risk of bleeding as an adverse event.
Still, the results of the existing research all add up, suggesting that this approach may be a highly desirable one going forward.
As Dr. Ralph Sacco, from the Miller School of Medicine at the University of Miami in Florida, reports, "The results of this large international trial, when added to the results of previous research, provide evidence to support the use of clopidogrel plus aspirin for 90 days among patients with minor ischemic stroke and high-risk TIA treated within 12 hours."
And the consistently promising outcomes, the researchers believe, will probably change the way in which patients are treated after a TIA or minor stroke.
"This trial is likely to change practice since most clinicians and patients are usually willing to accept the increased risk of hemorrhage to offset the disabling impact of a stroke."
Dr. Ralph Sacco