INTIMAL THICKENING & ANTIOXIDANTS IN HISPANICS & ANGLOS

背景资料。降脂降动脉粥样硬化的新发现 临床试验研究(CLAS)表明，颈总动脉内膜- 中层厚度(IMT)对低密度脂蛋白的反应更快、更明显 降压治疗优于冠状动脉造影术或颈动脉 粗糙度。来自灵长类动物模型的新数据也显示了超声波检测 高胆固醇饮食对血管内膜增厚的影响 12个月。这些发现提示颈动脉IMT是一种可靠的 动脉粥样硬化程度的快速反应标志物。 然而，在观察到的颈动脉治疗益处中，不到三分之一 在CLAS中发现的IMT是通过低密度脂蛋白胆固醇和高密度脂蛋白胆固醇的变化来解释的，提示 相关(或其他)因素更直接地与动脉粥样硬化有关 机械装置。 此外，芬兰的一项流行病学研究发现，低密度脂蛋白-C 仅在人群中预测颈动脉IMT(IMT)进展速度 有很高的血清(促氧化)铜水平。 假设。这些和其他数据支持动脉粥样硬化的模型 什么促进/抑制修饰低密度脂蛋白在细胞内的积聚 血清促氧化剂/抗氧化剂。 因此，拟议的流行病学研究旨在测试特定的 假设全球经济增长速度与 颈动脉内中膜厚度和低密度脂蛋白-C(β-增量-IMT/低密度脂蛋白)在患有[1] 血清促氧化剂水平较高(相对于较低水平的人 血清促氧化剂水平)，[2]较低的血清抗氧化剂水平， [3]较低的饮食抗氧化剂水平；和[4] 与戒烟相关的颈动脉IMT将在30%被检测到 月份。 可行性。这项研究的可行性源于[1]最近 超声颈动脉内膜厚度自动界面检测系统的研制 这将重复性误差降低了70%-90%；[2]需要调整的型号 饮食测量中的错误；以及[3]受试者从 稳定，合作，描述良好，多民族的人口 来自南加州爱迪生的员工。 设计。假说将通过纵向观察来检验 西班牙裔和非西班牙裔白人女性和男性的颈动脉内膜厚度。这个 将西班牙裔和妇女包括在内是因为他们在 研究人群(18%西班牙裔，40%女性)，根据最近的报告 在拉美裔美国人中，住院心肌梗塞的发生率较高。 4个种族-性别组各73人，年龄40-60岁(n-292)， 83名吸烟者和最近戒烟者(n-166人)将从 一项正在进行的研究中的员工。基线血液、饮食和潜能 混杂变量将与18个月和36个月(6、12、18、24)相关 吸烟者(S)30个月时颈动脉IMT的变化。

BACKGROUND. A new finding from the Cholesterol Lowering Atherosclerosis Study (CLAS), a clinical trial, indicates that common carotid intima- media thickness (IMT) responds more rapidly and more markedly to LDL-C lowering treatment than angiographic coronary stenosis or carotid roughness. New data from a primate model also show ultrasound detection of intimal thickening in response to a hypercholesterolemic diet within 12 months. These findings suggest that carotid IMT is a reliable and rapidly responding marker of extent of atherosclerosis. However, less than a third of the observed therapeutic benefit on carotid IMT found in CLAS was explained by change in LDL-C and HDL-C, suggesting that related (or other) factors are more directly linked to atherogenic mechanisms. In addition, a Finnish epidemiologic study found that LDL-C was predicative of rate of progression in carotid IMT (IMT) only in persons with high serum levels of (pro-oxidant) copper. HYPOTHESES. These and other data support a model of atherosclerosis in which intracellular accumulation of modified LDL is promoted/retarded by serum pro-oxidants/antioxidants. The proposed epidemiologic study is thus designed to test the specific hypotheses that the positive association between rate of increase in carotid IMT and LDL-C (beta deltaIMT/LDL) is greater in persons with [1] higher levels of serum pro-oxidants (relative to persons with lower levels of serum pro-oxidants), [2] lower levels of serum antioxidants, [3] lower levels of dietary antioxidants; and [4] that regression of carotid IMT associated with smoking cessation will be detected in 30 months. FEASIBILITY. The feasibility of the study stems from [1] recent development of automated interface detection for ultrasound carotid IMT that reduces reproducibility error by 70-90%; [2] models to adjust for error in dietary measures; and [3] availability of subjects from a stable, cooperative, well described, and multi-ethnic population of employees from Southern California Edison. DESIGN. Hypothesis will be tested with longitudinal observation of carotid IMT in Hispanic and non-Hispanic white women and men. The inclusion of Hispanics and women is motivated by their prevalence in the study population (18% Hispanic, 40% women), and by the recent report that incidence of hospitalized myocardial infarction is elevated in Hispanics. 73 persons from each of 4 ethnicity-sex groups aged 40-60 years (n-292), and 83 smokers and recent quitters (n-166) will be recruited from employees in an ongoing study. Baseline blood, diet and potential confounder variables will be related to 18 and 36 month (6, 12, 18, 24 and 30 month in smoker(s) changes in carotid IMT.