Relationship Of Hyperhomocysteinemia To Platelet Activation,Carotid Intima-media Thickness In Elderly Patient With Coronary Heart Disease

Objective: Endothelial dysfunction and the platelet activation are essential courses of atherosclerotic vascular disease(ASVD). Recent studies have shown that high level of plasma homocysteine(Hcy) is an independent risk factor of ASVD.Yet few researches have been down on the relationship of homocysteine to disorder of platelet function, which may be an import mechanism how homocysteine accelerate the process of atherosclerosis(AS). In our study, plasma homocysteine,CD62p(P-selectin) and carotid intima-media thickness(IMT) were measured and the relationship between them are analyzed in order to find out the effect of Hcy on platelet dysfunction and then on the AS.Methods: 59 elderly patient with coronary heart disease (according to the diagnosis criterion made by WHO in 1979) were enrolled, aged from 60 to 73 years old, including 48 men aged 66.5±3.8 and 11 menopause women aged 69.2±2.5years.Patients with acute coronary syndrome,diabetes,malnutrition,serious hepatic and renal dysfunction,malignant anemia were excluded, and platelet counts were within normal range. Carotid IMT was measured withHP2500 2D-ultrasound.All patients were asked to avoid protein-rich food for 3 days before the Hcy blood sample were drawn. the plasma were Separated by centifuring within 30 minutes after the blood being taken. the plasma was frozen in -72 centigrade refrigerator until being measured together by ELISA(Axis-Shield company. Germany). CD62p was detected by flow cytometer(FACS Vantage,BD company American。PE labeled CD62p monoantibody,PE labeled IgG1 are all productions of BD).Ultrasonography of carotid artery intima-media thickness were performed using a 7.5MHz high frequency linear array transducer of HP2500 made in U.S.A. The 1-cm segment proximal to the dilation of the carotid bulb was selected as the scanning district. The distance between the leading edge of the first bright line of the post wall (lumen-intima interface) to the leading edge of the second bright line (media-adventitia interface) indicated the carotid IMT.SPSS10.0 software pack was used to make statistical-analysis. Initially the homogeneity of variance between all the groups was analyzed. All the numerical data was shown as mean±standard deviation and students t test was used to establish significance. Chi-square test was used for analysis of catagorical data. Linear Correlation analysis was used to measure the coefficient of correlation about the correlation data. We took p＜0.05 as statistic significancelevel. Result:1 There were 59 elderly patient with coronary heart disease (48 males,11famales) participated and finished the study. All the patients were divided into two groups according to the level of Hcy :hyperhomocysteinemia group (Hcy>15μg/L) and normal group (Hcy≤15μg/L).(1)There was no statistical difference between the two groups about age,sex,blood pressure,serum total cholesterol, low-density lipoprotein lipid and smoking history.(2)The carotid IMT in hyperhomocysteinemia group was 1.032±0.127 and was 0.893±0.134 in the normal group.there was statistical difference(p<0.01); CD62p in hyperhomocysteinemia group was BI=0.0696±0.0185apprently higher than that of normal group BI=0.0486±0.0166,p<0.001.2 Then we assessed the relationship of plasma Hcy to CD62p and carotid IMT,we found:(1)There was positive correlation(r=0.449 p<0.01) between the plasma Hcy and carotid IMT;(2)There was positive correlation (r=0.441,p<0.001) between Platelet activation(CD62p) and carotid IMT;(3)There was Positive correlation (r=0.459,p<0.001) between Plasma Hcy and platelet activation(CD62p) too.Concolusions:1.About 40.7% old patients with coronary heart disease in our study had hyperhomocysteinemia and Hcy was an independent riskfactor of AS. in elderly patient with coronary heart disease, those have relatively higher Hcy level were more likely to have more serious AS and more activated platelets. Hyperhomocysteinemia might lead to excessive activation of platelet and act...