Effect Of Various Anti-platelet Therapeutic Strategies On The Platelet Aggregation In Elderly Patients With Acute Coronary Syndrome

Objective:To study the effects of aspirin and aspirin plus clopidogrel in different dosage on platelet aggregation and the safety to the elderly patients with acute coronary syndrome(ACS).Methods:Totally120patients with ACS were enrolled in Hunan provincial hospital from June2013to February2014.Patients were randomly divided to four groups according to age and drug usage:senile patients with normal dosage combination group(Group A, age≥75,n=30,aspirin100mg/d+clopidogrel75mg/d),senile patients with low dosage combination group(Group B,age≥75, n=30,aspirin100mg/d+clopidogrel50mg/d), senile patients with aspirin along group(Group C,age≥75, n=30,aspirin100mg/d), adult group with normal dosage combination group(Group D,55≤age<75,n=30,aspirin100mg/d+clopidogrel75mg/d) as control group, each patient receiving1week treatment. the changes of platelet aggregation were measured and adverse reactions were monitored in four groups pre-and post7day’s treatment, respectively.Results:(1) In each group there were significant difference between pre and post treatment in the changes of the arachidonic acid(AA) induced platelet aggregation and the adenosine diphosphate(ADP) induced platelet aggregation.(2) There were no significant difference of the AA induced platelet aggregation among the four groups(16.9±6.7,14.0±5.4,15.9±8.2,14.8±6.1,P>0.05).(3) There were no significant difference of the ADP induced platelet aggregation among the A、B、D groups(23.2±6.9,20.6±6.4,21.0±7.5, P>0.05).Compare with that of the group C,the ADP induced platelet aggregation of the group A、B、D is decreased more obviously(18.0±5.9vs23.2±6.9,18.0±5.9vs20.6±6.4,18.0±5.9vs21.0±7.5,P<0.05).(4)Patients with unstable angina pectoris in the four group,there were no significant difference of the efficacy rate on the improvement of clinical symptoms and electrocardiogram among the A、B、D groups. Compared with that of the group C, A、B、D groups was better in the effective rate on the improvement of clinical symptoms.(5) There were no significant bleeding for B、C、D group, but there are4cases of hypodermic bleeding for A group.Conclusion:(1) In elderly ACS patients, compared with aspirin monotherapy, combination of aspirin and clopidogrel can inhibit platelet aggregation further and improve clinical symptoms better after short-term treatment.(2) Compared with the combination in routine clopidogrel dose, aspirin plus clopidogrel in low dose has a higher safety in elderly patients without compromising the platelet inhibiting efficacy and symptom relief.