Your Heart Loves Aspirin

Heart attacks can be prevented with either high or low dose aspirin


While U.S. doctors tend to prescribe both doses of aspirin, the optimal aspirin dose has not been clear.

Brigham and Women's Hospital researchers have found that both high and low aspirin doses are effective in preventing heart events, particularly in patients with acute coronary syndromes, or symptoms related to coronary artery blockages.

"Discuss any medication change with your cardiologist."

Dr. Payal Kohli, cardiology fellow at Brigham and Women's Hospital and lead author of the study, said there was no observed difference between patients taking a high dose versus a low dose of aspirin as related to the prevention of recurring heart attack, stroke, cardiovascular death or stent thrombosis (a prompt closure of a blood vessel following implantation of a stent to prop open the artery.

Despite the finding, Dr. Kohli found a dramatic difference in how aspirin is prescribed around the world. He found that two-thirds of North American doctors prescribed high doses of aspirin, while the reverse was true for the rest of the world.

During the study investigators reviewed data from more than 11,000 acute coronary syndrome patients worldwide enrolled in the TRITON-TIMI 38 trial. The patients were randomly assigned to either clopidigrel (Plavix) or prasugrel (Effient), two different anti-platelet medications.

At the discretion of the clinicians, 7,106 patients received varying amounts of low dose aspirin, defined as less than 150 milligrams, while 4,610 were prescribed high dose aspirin.

Investigators found no significant difference in preventing heart attack, stroke, stent thrombosis or death from heart-related causes between the two groups. They did find that prasugrel was more effective at preventing adverse cardiovascular events as compared to clopidogrel, regardless of the aspirin dosage.

Researchers caution that patients receiving high dose aspirin were more likely to have more cardiovascular risk factors and higher cholesterol, while those receiving low dose aspirin were more likely to be Caucasian and have no history of hypertension. Because the study was not randomized, other treatment differences also could have affected the findings. A randomized, controlled study would be needed to confirm the findings.

The findings were recently presented at the American College of Cardiology's annual scientific sessions.

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Review Date: 
March 29, 2012