McMaster researchers have found there is a better way to prevent stroke for people
with irregular heartbeats.

According to research published in the New England Journal of Medicine Thursday,
the
new drug apixaban, currently under regulatory review, is better than aspirin in reducing
stroke in those with atrial fibrillation, otherwise known as an irregular heart beat.

The investigators report that in high-risk patients who have already had a stroke
or
warning stroke, apixaban reduces stroke from 8.3 per cent per year on aspirin to 2.5
per cent per year. This means that one stroke would be prevented, each year, for every
20 of these high-risk patients treated with apixaban.

The study also found that apixaban is superior to aspirin in reducing stroke in
patients
with atrial fibrillation who are unsuitable for the traditional therapy of warfarin. It
reduces the risk of stroke by more than 50% and, compared to aspirin, apixaban did
not significantly increase the risk of major bleeding.

Approximately one in four people aged 40 or older will develop atrial fibrillation
during
their lifetime. The biggest threat from the disorder is a greatly increased risk of stroke,
which is five times higher than for others. Blood thinners such as warfarin reduce this
risk but are very hard to use successfully. About a third of patients are unsuitable for
the treatment with warfarin, a vitamin K antagonist, which requires life-long blood
monitoring.

According to principal investigator Stuart Connolly, apixaban could vastly improve
the
quality of life for patients who cannot take warfarin.

“Patients with a stroke who have atrial fibrillation and who cannot take warfarin are
at
particularly high risk of recurrent stroke,” said the professor of medicine at the
Population Health Research Institute of McMaster and Hamilton Health Sciences. “It is
great to know that we now have a drug that can reduce recurrent strokes substantially
in these patients and which most patients will be able to take without the need for
monitoring.”

The full report published on the journal's website follows preliminary results of the
AVERROES study of apixaban presented last year. The report is also being presented
Thursday at the American Stroke Association's international conference in Los Angeles,
CA.

The international study, which involved more than 5,500 patients in 522 centres in
36
countries, was funded by pharmaceutical companies Bristol-Myers Squibb and Pfizer
Inc.