摘要
To the Editor： We read the article by Ke et al with great interest, in which they investigated the usage of aspirin for the secondary prevention of ischemic stroke. The incidence of ischemic stroke and transient ischemic attack assessed by onset of clinical symptoms exhibits a marked circadian variation with a peak period during the morning. Stroke usually occurs unexpectedly or more frequently in the morning hours, between 7-12 a.m. In this morning period there is a higher aggregability of thrombocytes. Patients usually take aspirin in the morning for prevention as the treatment regimen is one tablet per day to be swallowed without chewing at least 30 minutes before breakfast （Figure）. The highest plasma level of the drug occurs after the morning peak-incidence of the thromboembolic event, suggesting lower prophylactic effect of aspirin.
To the Editor： We read the article by Ke et al with great interest, in which they investigated the usage of aspirin for the secondary prevention of ischemic stroke. The incidence of ischemic stroke and transient ischemic attack assessed by onset of clinical symptoms exhibits a marked circadian variation with a peak period during the morning. Stroke usually occurs unexpectedly or more frequently in the morning hours, between 7-12 a.m. In this morning period there is a higher aggregability of thrombocytes. Patients usually take aspirin in the morning for prevention as the treatment regimen is one tablet per day to be swallowed without chewing at least 30 minutes before breakfast （Figure）. The highest plasma level of the drug occurs after the morning peak-incidence of the thromboembolic event, suggesting lower prophylactic effect of aspirin.
