Press Release - Mar 24, 2012
Aspirin: High or Low Dose Following Heart Attack?
report no significant difference in high versus low dose aspirin in preventing
recurring cardiovascular events.
Each year, more than one million Americans suffer a heart attack and nearly
all patients are prescribed a daily aspirin and an antiplatelet medication
during recovery. However, the optimal aspirin dose has been
unclear. Now, new research from Brigham and Women's Hospital (BWH)
reports that there is no significant difference between high versus low dose aspirin
in the prevention of recurring cardiovascular events in patients who suffer
from acute coronary syndromes (ACS), which are characterized by symptoms
related to obstruction in coronary arteries, which supply blood to the
heart. These findings are presented at the American College of Cardiology Scientific Sessions on March 24, 2012.
observed no difference between patients taking a high dose versus a low of
aspirin as it relates to cardiovascular death, heart attack, stroke or stent
thrombosis," said Payal Kohli, MD,
fellow at BWH and researcher in the TIMI Study Group, who is
the lead author on this study. "Interestingly, we did find a dramatic
difference in practice patterns of physicians in North America compared to
those in the rest of the world," Kohli said. "North American physicians
prescribed a high dose of aspirin for two-thirds of all their patients, while
the exact reverse was true of the rest of the world. International physicians
prescribed a low dose of aspirin to more than two-thirds of their
patients." Dr. Stephen D. Wiviott, a
cardiologist at BWH and researcher in the TIMI Study Group, is the senior
author on the study.
analyzed data from more than 11000 patients from around the world that were
enrolled in the TRITON-TIMI 38 trial, which randomized ACS patients to receive
either clopidigrel or prasugrel, two different antiplatelet medications.
Some patients were prescribed high doses of aspirin following a heart
attack, while others, low doses. The aspirin dose was prescribed at the
clinician investigator's discretion and the analysis included 7,106 patients
who received low dose aspirin, defined as 150 mg or less, and 4,610 patients
who received high dose aspirin, defined as 150 mg or more. Researchers reported
that there was no significant difference observed in the prevention of the
combination of heart attack, stroke, cardiovascular death or the prevention of
stent thrombosis between the groups that received high or low dose
aspirin. Prasugrel was more effective at preventing major adverse
cardiovascular events than clopidogrel, regardless of whether patients received
low or high dose aspirin.
also present that patients who received high dose aspirin were more likely to
have more cardiac risk factors and have higher cholesterol. Patients who
received low dose aspirin were more likely to be white and have no prior
history of high blood pressure.
authors caution that because this is not a randomized study, there may be other
treatment differences that could have affected the results and a randomized
controlled trial would be needed to definitively establish that no difference
existed in outcomes between aspirin dose regimens. These data are, however,
consistent with previous reports.
authors reinforce that all medication changes should be made only after
discussion with your physician.
The TIMI (Thrombolysis In Myocardial Infarction) Study Group was founded by
Dr. Eugene Braunwald in 1984, and has conducted numerous practice-changing
clinical trials in patients with cardiovascular disease or risk factors for
cardiovascular disease. The TIMI Study Group is affiliated with Brigham
and Women's Hospital and Harvard Medical School, and is chaired by Dr. Marc