A new study shows that aspirin, used for decades to reduce the risk of cardiovascular problems, may provide little or no benefit for certain patients who have plaque buildup in their arteries.
Researchers tracked the health histories of over 33,000 patients with atherosclerosis—narrowed, hardened arteries—and determined that aspirin is only marginally beneficial for those who have had a previous heart attack, stroke, or other blood-flow issues involving arteries—and offers no benefit for atherosclerosis patients with no prior heart attack or stroke.
Because the findings are observational, further study that includes clinical trials are needed before definitively declaring that aspirin has little or no effect on certain atherosclerosis patients, says cardiologist Anthony Bavry, associate professor of medicine at the University of Florida.
“Aspirin therapy is widely used and embraced by cardiologists and general practitioners around the world. This takes a bit of the luster off the use of aspirin.”
The findings, published in the journal Clinical Cardiology, don’t undercut aspirin’s vital role in more immediate situations: If a heart attack or stroke is underway or suspected, patients should still take aspirin as a treatment measure, Bavry says. “The benefit of aspirin is still maintained in acute events like a heart attack or a stroke.”
Among more than 21,000 patients who had a previous heart attack or stroke, the research shows a marginally lower risk of subsequent cardiovascular death, heart attack, or stroke among aspirin users.
But, for those atherosclerosis patients who had not previously had a heart attack or stroke, aspirin appeared to have no effect. The risk of cardiovascular death, heart attack, and stroke was 10.7 percent among aspirin users and 10.5 percent for non-users.
“If we can identify those patients and spare them from aspirin, we’re doing a good thing.”
Patients who enrolled in the nationwide study were at least 45 years old with coronary artery disease, cerebrovascular disease, or peripheral vascular disease. Their medical data were collected between late 2003 and mid-2009.
The researchers did identify one group that got some benefit from aspirin—people who had a coronary bypass or stent but no history of stroke, heart attack, or arterial blood-flow condition. Those patients should clearly stay on an aspirin regimen, Bavry says.
Discerning aspirin’s effectiveness for various patients is also important because the medicine can create complications, including gastrointestinal bleeding and, less frequently, bleeding in the brain. Because of insufficient data, the current study wasn’t able to address the extent of aspirin’s role in bleeding cases.
Patients with atherosclerosis or peripheral vascular disease shouldn’t quit aspirin therapy without talking to their doctor, Bavry says.
“The cardiology community needs to appreciate that aspirin deserves ongoing study. There are many individuals who may not be deriving a benefit from aspirin. If we can identify those patients and spare them from aspirin, we’re doing a good thing.”
Scientists from France, England and Harvard Medical School collaborated on the research. Patient data came from from the Reduction of Atherothrombosis for Continued Health registry, which the Waksman Foundation and pharmaceutical companies Sanofi and Bristol-Myers Squibb supported.
Source: University of Florida