Aspirin shows faculty against staph
Aspirin, the wonder drug, may have yet another use. Its pain-killing and cardiovascular effects are well known, but Dartmouth researchers only recently found that catheter-dependent dialysis patients who take aspirin daily have a much lower incidence of deadly Staphylococcus aureus infections. Catheters—tubes threaded into a vein—are not the safest way to have dialysis because they offer a point of entry for bacteria. "The best known way to have dialysis," says Martin Sedlacek, M.D., a DHMC nephrologist, is through a fistula, a surgical connection between an artery and a vein. Over several months, the increased blood flow from the artery causes the vein to thicken so it can tolerate repeated sticks from dialysis needles.
Deadly: Yet almost a third of dialysis patients in the U.S. still rely on catheters because they either don't want to have fistula surgery or didn't have time for it before starting dialysis. As a result, 3% to 4% of long-term dialysis patients contract potentially deadly S. aureus infections each year. John Gemery, M.D., an interventional radiologist who places catheters, and Ambrose Cheung, M.D., a microbiologist, noticed this problem and wondered if aspirin, which has known antistaphylococcal effects, might help prevent infections. So they teamed up with Sedlacek and Brian Remillard, M.D., chief of nephrology at DHMC, plus a researcher at the University of California
at Los Angeles, to investigate their hypothesis.
The team looked at blood cultures from 872 DHMC patients who received dialysis through a catheter from 1995 to 2005. They divided the patients into three groups based on their daily aspirin intake. The group taking the most aspirin, 325 mg daily, had a much lower rate of S. aureus infection, only 13 infections per 100 patients with a catheter for one year,
compared to 34 infections per 100 patient-catheter-years for those taking no aspirin.
Bottle: But dialysis patients using catheters shouldn't go running for the aspirin bottle yet. "This is just one first study," cautions Sedlacek. He and his colleagues will be looking at national data next to see if they can find a similar pattern. For now, the best thing that dialysis patients can do is get a fistula, he says.
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