(RxWiki News) Stroke risk runs high for individuals with atrial fibrillation. Taking blood thinners, however, may not only lower this risk, it may reduce the likelihood of brain damage if stroke happens anyway.
Atrial fibrillation (Afib) is the most common irregular heart rhythm (arrhythmia). Because people with the condition are about five times more likely to have a stroke, according to the National Stroke Association, medication to prevent clots from forming is usually prescribed.
While research has already shown anticoagulants (blood thinners) can cut stroke risk, a new study has found that the medication may lower the odds of dying and brain damage if stroke should still happen.
"If you have atrial fibrillation, ask your doctor how to lower stroke risk."
Søren Paaske Johnsen, MD, PhD, a senior research consultant in clinical epidemiology at Aarhus University in Denmark, and colleagues examined data on 11,356 Danes with atrial fibrillation.
"Atrial fibrillation is a common condition affecting about 2.7 million Americans. Although it is most common over the age of 60, it can strike at any age," said Sarah Samaan, MD, cardiologist and physician partner at the Baylor Heart Hospital in Plano, Texas.
The Afib patients in this study had been admitted to the hospital with acute stroke between 2003 and 2009. Stroke cases included both ischemic (caused by a blocked blood vessel) and hemorrhagic (cause by weakened blood vessel that ruptures).
A total of 2,492 patients (about 22 percent) were receiving anticoagulant medication when they were admitted with stroke. The scientists compared 2,175 patients who were receiving oral anticoagulant therapy to a matching number of patients who were not receiving such medication at the time of admittance.
Within 30 days of admittance after stroke, the degree of brain damage and the death rate appeared to be lower for those taking blood thinners, according to the authors of this study.
These researchers evaluated patient brain function using the Scandinavian Stroke Scale, which assesses factors such as consciousness and movement of the eyes, arms, hands and legs.
Of patients evaluated for stroke events, 35 percent of the non-medicine group had stroke-related events, compared to 28 percent in the antigoagulant therapy group.
Of 2,175 in the non-medicine group, 433 died (19.9 percent) within 30 days of admittance for stroke compared to 382 (17.6 percent) in the antigoagulant therapy group.
Patients with Afib are susceptible to stroke because the condition produces an irregular heartbeat, which allows blood to pool in the heart. When blood collects like this, it tends to form clots, which can be carried to the brain and cause stroke. The disease primarily affects individuals over the age of 50.
The anticoagulation medication warfarin (brand Coumadin) is often prescribed to Afib patients, but the medication can lead to bleeding complications. Dr. Johnsen warned that a small percentage of those who take anticoagulants increase their risk of having a brain hemorrhage.
"Treatment with anticoagulant medicine balances on a bit of a razor's edge, as we know that it will help a large group of patients, but at the same time can give side-effects in the form of brain hemorrhages for a small group,” said Dr. Johnsen in a press release. “But research, including our latest study, clearly shows that there may be great benefits to be gained by not being quite as cautious with the medicine as we have been previously.”
"Powerful bood thinners like Coumadin, Pradaxa, and Xarelto are not appropriate for everyone. For instance, the risk might outweight the benefits for someone whose risk of stroke is very low. Generally, younger, otherwise healthy people are treated with aspirin, a weaker blood thinner. Very frail people may be at high risk for bleeding complications, so the drugs might not be right for them," said Dr. Samaan, who was not involved in this study.
"For the majority of people, however, blood thinners can save and protect lives. Since 15-20 percent of strokes in this country are due to atrial fibrillation, the imapct of blood thinners is potentially huge," she said.
"This study shows us that even in those cases in which the drugs don't prevent strokes, they can prevent or limit permanent damage and save lives," she said.
This study was published in January in the American Heart Association journal Stroke.
This study received support from Bristol-Myers Squibb and Pfizer. Several of the study's authors reported potential conflicts of interest with a number of pharmaceutical companies, including Bristol-Myers Squibb and Pfizer.