May 9 2007
Nearly a quarter of a million Americans each year may be hospitalized with bleeding complications caused by needlessly taking a daily dose of an adult-sized aspirin rather than a baby aspirin to prevent a heart attack or stroke.
A study by a group of UK HealthCare Linda and Jack Gill Heart Institute cardiologists found that the commonly prescribed 325 mg adult tablet may be more than many people need each day. The study, which is published in today's issue of the Journal of the American Medical Association, found that doses higher than a baby aspirin, 75 to 81 mg, are no better at preventing cardiovascular events long-term and are associated with increased risk of gastrointestinal bleeding.
Gill Heart Institute cardiologists and University of Kentucky College of Medicine faculty Dr. Charles Campbell, Dr. Steven R. Steinhubl and Dr. Susan Smyth, along with Dr. Gilles Montalescot of the Instjtut de Cardiologie-Centre Hospitalier Universitaire Piti--Salptrire in Paris, France, systematically reviewed published data regarding clinical studies involving aspirin dosing. Even in patients with diabetes, who may be more difficult to treat, they found no large-scale studies that support higher doses of aspirin.
"While aspirin is an effective drug for the prevention of clots," said Campbell, lead author of the report, "the downside of aspirin therapy is an increased tendency for bleeding (particulary from the GI tract). We believe the minimum effective dose should be utilized (75-81 mg)." However, Campbell notes, "We also believe more study in this area is warranted to determine if the minimum dose is effective for everyone, or if dose should be adjusted from person to person."
Aspirin is the most-used drug in the world. More than 50 million people, or 36 percent of the adult population in the United States, consume 10 to 20 billion aspirin tablets each year to protect their hearts from clots, which are the leading cause of heart attacks and strokes.
"Patients should check with their doctor to be sure, but there is almost no one who needs to take more than 81 mg of aspirin a day for protection from heart attacks," Steinhubl said. Going forward, the study notes that the greatest challenge ahead for physicians may be to determine how to identify the best blood-thinning regimen for their patients.