Once-a-day tablet offers new hope on strokes

A new-generation drug that works by blocking a substance in one’s blood that is involved in the development of blood clots—called factor Xa—is set to bring hope to more than 2 percent of Filipinos who are in danger of suffering from strokes and other potentially deadly attacks caused by atrial fibrillation.

Bayer HealthCare, the healthcare and medical products arm of German chemicals and pharmaceuticals giant, Bayer, announced this week the arrival of once-daily rivaroxaban (Xarelto) to reduce this risk of stroke and systemic embolism.

Rivaroxaban is currently the only orally taken anticoagulant—an agent used to prevent the formation of blood clots—approved by the United States Food and Drug Administration to protect patients with nonvalvular atrial fibrillation.

Possible improvement

According to Dr. Christopher Hammett, an interventional cardiologist at the Royal Brisbane and Women’s Hospital in Brisbane, Australia, rivaroxaban is now being viewed as possible improvements over the long-time standard, warfarin.

Warfarin, while inexpensive, requires long-term treatment, dietary restrictions as well as drug restrictions (because it interacts with many substances and could cause dangerous internal bleeding).

Rivaroxaban is the first oral anti-clotting drug approved to treat and reduce the recurrence of blood clots since the approval of warfarin nearly 60 years ago.

Interruption

Stroke, the second-leading cause of death in the Philippines, is caused by the interruption of the blood supply to the brain, usually because of a blockage caused by a clot. When this happens, the supply of oxygen and nutrients is cut off, causing damage to the brain tissue.

Atrial fibrillation, on the other hand, is considered to be the precursor to various serious cardiovascular complications such as stroke as well as systemic embolism (the likelihood of strokes in patients suffering from atrial fibrillation increases by about five times) and is caused by a “glitch” in the heart’s electrical system that makes the upper chambers of the heart to contract very fast and irregularly (fibrillate).

Atrial fibrillation related strokes are 50 percent more likely to cause death or paralysis.

According to Dr. Norbert Lingling Uy, immediate past president of the Philippine College of Physicians and past president of the Philippine Heart Association, around 70 percent of stroke in the Philippines involved the obstruction of blood vessels in the brain by blood clots, which results in negative oxygen flow to the brain.

This will cause the victim to experience sudden weakness or numbness of the face, arm or leg, most often on one side of the body. Other symptoms include confusion, difficulty speaking or understanding speech; difficulty seeing with one or both eyes; difficulty walking, dizziness, loss of balance or coordination; severe headache with no known cause; fainting or unconsciousness.

Effects of stroke

The effects of a stroke depend on which part of the brain is injured and how severely it is affected. A very severe stroke can cause sudden death.

The doctor cited uncontrolled hypertension—where one detects high blood pressure but is hesitant to go to the doctor to consult or where a hypertensive patient isn’t taking medicine, or medicine is taken in inadequate amounts—as the more common cause of stroke.

Other factors cited include having diabetes, prior stroke, as well as being over the age of 60.

It’s said that if one experiences a stroke, one is in what is known as a “30-30-30” situation wherein there is a 30 percent chance of dying, 30 percent of being fortunate enough to go to back to normal, and 30 percent of being left with severe disability.