Medications given to heart patients to prevent blood clots can double, triple or even quadruple the risk of stomach or intestinal bleeding, U.S. researchers report.
Drugs such as aspirin, warfarin or Coumadin and Plavix are often given in combination to prevent blood clots in patients who've had a stroke or heart attack.
While it's known that the drugs each carry their own risk of stomach bleeding or ulcers, the risk of taking the drugs in combination hasn't been well-studied.
So Dr. Neena Abraham of Baylor College of Medicine in Houston, Texas, used U.S. pharmacy data and medical records from the Veterans Affairs Department to find patients aged 60 to 99 who had been given four different combinations of clot-preventing drugs.
Some got aspirin and an antiplatelet such as Plavix; others got an antiplatelet drug and an anticoagulant such as warfarin; others got aspirin and warfarin; and some got all three.
Of the more than 78,000 patients studied, 30.4 per cent were prescribed some combination of anti-clotting drugs, and 1,061 of these had bleeding events that needed immediate medical attention within the first year.
The aspirin-antiplatelet combination doubled the risk, while an aspirin-anticoagulant combination tripled the one-year bleeding risk.
Patients who got all three drugs had a four-fold increase in the risk of gastrointestinal bleeding within one year, Abraham said in a presentation at the Digestive Disease Week meeting in Chicago.
The least harmful combination was an anticoagulant and an antiplatelet, such as combining warfarin and Plavix.
Abraham said triple therapy was most commonly given to younger patients in the study -- those aged 60 and 69 years of age -- and likely reflected recent changes in cardiac care that found that combo most effective in preventing secondary attacks.
Abraham said the findings suggest the need for a careful balancing of the risks and benefits of these drugs. She said some heart patients on triple therapy may want to ask their doctor about dropping down to a dual or single therapy.
"We know they are healthy for the heart at preventing strokes and heart attacks, but what physicians now need to consider is short-term potential risks of GI bleeding versus the potential long-term benefits of being on these protective drugs," she told reporters at the conference.
