Platelet/Thrombocyte
Risk Reduction with ASA
| Risk Reduction With ASA (%) | ||||
|---|---|---|---|---|
| Review | All Doses |
Low Dose |
Medium Dose | High Dose |
| Algra and van Gijn (1996) 10 trials; total N=6171 |
13 | 13
< 100 mg/day |
9
300 - 325 mg/day |
14
> 900 mg/day |
| Tijssen (1998)
10 trials; total N=9893 |
13 | 13
50 - 100 mg/day |
9
250 - 500 mg/day |
13
1000 - 1500 mg/day |
| Johnson et al (1999)
11 trials; total N=9629 |
15 | Daily doses ranged from 50 to 1500 mg |
||
Several clinical studies have suggested that low doses of ASA provide antiplatelet activity equivalent to that of high doses. The relative risk reductions for cerebrovascular and cardiovascular events provided by high-dose, medium-dose, and low-dose ASA have been assessed in several meta-analyses. Risk reductions ranged from 9% to 15%, with no advantage for high-dose ASA. In ESPS 2, the relative risk reduction provided by low-dose ASA alone (RRR 19% at 50 mg/day) was comparable to its efficacy in many other trials.
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