CHICAGO - Antibiotics failed to ward off heart trouble in the biggest study to test the theory that low-level infections play a major role in triggering heart attacks.
But researchers said they won't give up on the idea.
The study in Wednesday's Journal of the American Medical Association involved 7,722 heart attack patients from North America, Europe, Argentina and India. Taking antibiotics failed to reduce their risk of death or further heart trouble over two years.
In recent years, some research has suggested that painless inflammation from such things as lingering respiratory or urinary infections or even chronic gum disease triggers heart attacks by contributing to the formation of clots in the blood vessels.
Smaller studies have suggested that antibiotics targeting such infections might reduce the risk of heart disease, and some doctors have begun to give heart patients antibiotics.
The new study suggests that practice is premature, said Dr. Christopher O'Connor of Duke University, the lead author.
Still, his study suggests there might be some short-term benefits from antibiotic treatment and a slight reduction in heart trouble in patients with more than one risk factor, such as those who smoke and have diabetes.