The Study Of Structure And Function Of Carotid Ultrasound Changing With Age In Elder Healthy Adults

AimStudies indicate that cardio - cerebrovascular disease is a main reason which causes elder adults'death. The pathological basis of it is ahterosclerosis. Age has been found to be the chief determinant of atherosclerotic progression. A series changes occur with human aging in arteries, which causes the intensity and elasticity of the wall decreasing with age, which accelerate the atherosclerotic occurrence and development . Duplex ultrasound can generalize the alteration in carotid arterial structure function and hemodynamic parameters . The possible carrying risk factors of atherosclerosis are strictly excluded in present study. The purpose is to examine the relation of carotid ultrasonographic changes to the aging process, reveal the mechanism of atherosclerosis and provide preventive and diagnostic basis for clinical cardio - cerebrovascular disease.Method一 Subjects and GroupsSubjects who have hypertension coronary heart disease diabetes cardio -cerebrovascular disease and hyperlipoproteinemia are excluded. They are non-smokers with normal blood pressure plasma glucose concentration and plasma lipoprotein concentration, further evaluated by ECG . Aged from 30 to 89 years old,male 105 and femal 99. They are divided into four groups;30 -44years old 45 -59years old 60 -74years old,, and 75 years old.二 MethodCarotid ultrasound images are obtained in all subjects. Evaluation includes intima - media thickness (IMT) of common carotid artery (CCA) diastolic di-ameter(D) and serious degree and the numbers of plaque occurrence. Bloodflow parameters include peak systolic velocity ( SPV ) end diastolic velocity ( EDV) resistance index ( RI) and pulsatility index( PI).三 Statistical AnalysisSPSS11.5 statistical software is used for analysis. The arithmetic mean and standard deviation were used for descriptive statistics. Differences among groups are estimated using ANOVA procedure. To describe the dependency of the variables on age,we use liner regression analysis. A multiple stepwise regression a-nalysis is applied to CCAIMT D SPV EDV RI and PI as the dependent variable. Significance of differences in occurrence of plaques is calculated by x2 test. Probability value <0.05 is considered to indicate significance.Result一 Differences in index of CCAIMT D SPV EDV RI and PI among groups is significiant,P < 0.001,especially in groups of 60 years old.二 There is a liner correlation between IMT and age. The rate of plapue occurrence also increase with age, and IMT increase with the degree of plaque.三 CAD RI and PI increase significantly with age,but SPV and EDV have the reverse result.四 Stepwise regression analysis indicate that age is the only independent predictor in CCAIMT D SPV EDV RI and PI.Conclusion一. There is a liner increase in CCAIMT with age, the rate and degree of plaques increase with IMT thickening too, which reflects that IMT thickening is an early change in atherosclerosis.二. There is a liner increase in CCAD RI PI with age, SPV EDV have reverse results, the only independent factor to effect CCAIMT D SPV EDV RI and PI in healthy is age.三. A multiparametric assessment may contribute to a better understanding of vascular aging.