Evaluating the effect of different doses of aspirin on the platelet inhibition rate by thromboelastography / 中国医师进修杂志

ABSTRACT

Objective To evaluate the effect of different doses of aspirin on the platelet inhibition rate by thremboelastography.Methods One hundred and eighty patients with ischemic stroke or transient cerebral ischemic attack (TIA) were randomly divided into aspirin 100 mg/d group (60 patients),aspirin 200 mg/d group (60 patients) and aspirin 300 mg/d group (60 patients) according to the order of treatment.The platelet inhibition rate which arachidonic acid pathway induced was measured by thromboelastography and compared at different time points (before medication; 7 days,6 months,1 year after medication).Results There were significant differences in the platelet inhibition rate after medication at different time points compared with that before medication in three groups (P ＜ 0.05).After medication at different time points,the platelet inhibition rate of aspirin 100 mg/d group and aspirin 200 mg/d group was gradually decreasing.On the contrary,that of the aspirin 300 mg/d group showed gradually increasing.Cross-sectional comparison of the three groups at different time points showed that there was no significant difference in the platelet inhibition rate among three groups before medication,7 days,6 months after medication (P ＞ 0.05).However,there was significant difference at 1 year after medication (P ＜ 0.05).The platelet inhibition rate inaspirin 300 mg/d group [(93.8 ± 18.6)％] was higher than that in aspirin 200 mg/d group [(83.7 ± 11.2)％]and aspirin 100 mg/d group [(76.6 ± 12.8)％] (P ＜ 0.05).During medication there were 9 patients of less than 50％ platelet inhibition rate in aspirin 100 mg/d group,5 patients in aspirin 200 mg/d group,3 patients in aspirin 300 mg/d group,and 2 patients of peptic ulcer bleeding in aspirin 300 mg/d group.Conclusions The appropriate dose of aspirin (100,200,300 mg/d) can play a very good anti-platelet effect.Increasing the dose on the basis of 100 mg/d,the platelet inhibition rate shows no increase in the short-term (≤6 months),but in the long-term (1 year) there may be differences.It may be associated with less aspirin resistance and the relative increasing bleeding risk.