The Study Of Cloidogrel Resistance In Old Patients

Objective Arterial thrombosis is a main cause of death in patients suffering from of gronary heart disease hypertension and diabetes mellitus. However, recent studies have showed that some patients have hypoergy or inexcitability to clopidogrel. But materials about clopidogrel resistance in old people are scarce. Our study was designed to investigate the incidencerate and influential factors of clopidogrel resistance in old patients.Methods 120 patients were collected randomly from the people who were hospitalized in PLA General Hospital during January 2006 to May 2007 according to following standards: more than 80 years old, clopidogrel medication for the first time or drug withdraw of clopidogrel for at least 7 days, no ticlopidine or heparin medication, no acute or chronic hematological system disease, platelet is more than 100 thousand, without severe liver or kidney disfunction, no bleeding, cancer or diseases of immune system. Medication is 75mg clopidogrel per day. 5μMADP was used as stimulus to detect the rate of platelet aggregation (RPA) on baseline and 5 days after medication. The difference of ▲RPA[%]≤10% is regarded as the standard of clopidogrel resistance (CR) and the patients were separated into two groups: CR group and non-CR group. Blood biochemistry markers, blood clotting markers, glycosylated hemoglobin, RPA, expression rate of CD62P and GPⅡb/Ⅲa were analysed before treatment. The last three indicators were also measured after 5 days of medication. The age, sex, body mass index (BMI), family history, smoking, baseline disease and drugs were analyzed.Results There were 33 cases of clopidogrel resistance (27.5 %). CR group has higher incidence of diabetic and higher level of Hs-CR density(P<0.05). Positive expression of GPⅡ b/Ⅲa was higher in CR group than that in no-CR group. Other clinical characters and blood marker had no differences. Coincidence rate between RPA and positive expression of GPⅡb/Ⅲa is 79.17%, the sensitivity of GPⅡb/Ⅲa measures is 0.55, the specificity is 0.89, and the K value is 0.66.Conclusion 1. The incidence of clopidogrel resistance is 27.5% in old people, it indicates that clopidogrel resistance is very common in old people. 2. The positive expression of GP II b/IIIa and level of Hs-CRP were higher in CR group than that in no-CR group. 3. There are some relationship between RPA and the positive expression of GP Ⅱ b/Ⅲa.