Learning Center
New In Coagulation
Wednesday, June 4, 2008
Lower doses of aspirin are just as effective in preventing cardiovascular events as higher doses
More evidence that lower doses of aspirin are just as effective in preventing cardiovascular events as higher doses comes from a systematic review published in the May 9 issue of JAMA.
The authors, led by Charles L. Campbell, MD, from the University of Kentucky, in Lexington, conclude: "Currently available clinical data do not support the routine, long-term use of aspirin dosages greater than 75 to 81 mg/day in the setting of cardiovascular disease prevention. Higher dosages, which may be commonly prescribed, do not better prevent events but are associated with increased risks of gastrointestinal bleeding."
Dr. Campbell commented to heartwire, "Recommendations vary but most state aspirin should be taken chronically at a dose anywhere between 75 mg and 325 mg daily, and some even include doses up to 1300 mg. We need to rethink this advice. We know that the risk of bleeding increases with higher doses, and this is now even more of an issue as more patients are also taking clopidogrel. But the beneficial effect of aspirin on clinical events does not appear to increase with increasing doses. So the guidelines should change to just recommend low doses -- 75 or 81 mg. A lot of people buy aspirin over the counter and they need clear information about which dose to take." He added that there was much evidence that aspirin is beneficial for high-risk patients, but the evidence is less robust for lower risk patients (ie, primary prevention)."
Co-author Steven R. Steinhubl, MD, from the University of Kentucky in Lexington pointed out that even 75 or 81 mg is probably overdosing aspirin, as studies have shown that platelet thromboxane is completely inhibited with just 30 mg of aspirin taken long term. "The 75- to 81-mg dose has been arrived at completely arbitrarily as these doses are just one quarter of a 300- or 325-mg tablet," he said.
50 Million People Take Aspirin for CVD Prevention in United States Alone
Donna Castellone
|
