Epidemiology Of Silent Myocardial Ischemia In Apparently

无症状性心肌缺血的流行病学

• 批准号: 6674172
• 负责人: Samer Najjar
• 金额: --
• 依托单位: NATIONAL INSTITUTE ON AGING
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6674172
• 关键词: aging; cardiovascular disorder diagnosis; cardiovascular disorder epidemiology; cardiovascular disorder prevention; clinical research; coronary disorder; diagnosis design /evaluation; exercise; heart rate; human subject; myocardial ischemia /hypoxia

SUMMARY OF WORK: Our laboratory uses multiple approaches to investigate potential predictors of coronary heart disease in apparently healthy subjects. A. The rate at which heart rate (HR) declines after cessation of maximal treadmill exercise has been proposed as an independent predictor of future coronary events (CE) both in symptomatic and asymptomatic populations. To examine this hypothesis in apparently healthy subjects, we determined the relationship between the decline in HR between peak exercise and 2 minutes post-exercise (HR recovery-2') in over 1000 Baltimore Longitudinal Study of Aging (BLSA) volunteers and subsequent development of CE (angina pectoris, myocardial infarction or coronary death). In a model containing standard coronary risk factors, treadmill aerobic capacity and ST segment response to exercise, age, gender, serum cholesterol level, aerobic capacity and ST-segment response, but not HR recovery-2' were independent predictors of CE. These findings cast doubt on the value of HR recovery as a coronary risk factor in subjects without apparent heart disease. B. To determine whether the apoliprotein E4 allele (apo E4) is associated with an increased risk of coronary events (CE) i.e. angina pectoris, myocardial infarction or sudden death, we determined apoE genotype in 731 asymptomatic Baltimore Longitudinal Study of Aging (BLSA) volunteers followed for a mean period of 17 years. Although the 200 subjects with at least one apo E4 allele and the 531 without apo E4 had similar levels of conventional coronary risk factors, CE developed in 21% of apo E4 subjects vs. 13% in the other group. On multivariate Cox analysis, the apo E4 allele was a strong independent predictor of events in men(RR=2.9,p<0.0001), but not in women (RR=0.9,p=ns). C. We examined the relative contributions of leisure time physical activity (LTPA) and aerobic fitness (peak VO2) during treadmill exercise to development of CE in 689 clinically healthy men 18-93 years old. Over a mean follow-up of 13.4 yrs, a CE occurred in 63 (9%). In multivariate Cox model, higher peak VO2 was protective against CE, both in men <65 years [RR=0.53/SD] and those >65 years [RR=0.61/SD]. In contrast, high intensity LTPA (greater than or equal to 6METs)had an independent protective effect in older but not younger men. Thus, strategies to increase LTPA may be more effective in reducing the CE incidence in older than younger men.

工作摘要：我们的实验室使用多种方法来研究明显健康的受试者中冠心病的潜在预测因子。答：在停止最大跑步机运动后，心率（HR）下降的速度已被提议作为对症状和无症状人群中未来冠状动脉事件（CE）的独立预测指标。为了检验在看似健康的受试者中的这一假设，我们确定了运动后运动峰值和运动后2分钟之间的HR下降（HR Recovery-2'）之间的关系，超过1000多个巴尔的摩纵向研究（BLSA）志愿者与CE的后续发展（Angina Pectoris，Pectoris，pecoris，心肌梗死或脊髓梗死或脊髓梗死）。在包含标准冠状动脉危险因素的模型中，跑步机的有氧运动能力和对运动，年龄，性别，血清胆固醇水平，有氧运动能力和ST段响应的响应是CE的独立预测指标。这些发现对没有明显心脏病的受试者中人力资源恢复作为冠状动脉危险因素的价值产生了怀疑。 B.确定载脂蛋白E4等位基因（APO E4）是否与冠状动脉事件的风险增加有关（CE），即心绞痛，心肌梗塞或猝死，我们确定了731年无症状的Baltomore Baltimore Baltimore纵向研究（BLSA）volnununteer的apoe基因型。尽管有至少一个APO E4等位基因和没有APO E4的531个受试者具有相似水平的常规冠状动脉危险因素，但CE在另一组中有21％的Apo E4受试者在21％的APO E4受试者中发展。在多元COX分析中，Apo E4等位基因是男性事件事件的强烈独立预测指标（RR = 2.9，p <0.0001），但在女性中却没有（RR = 0.9，p = ns）。 C.我们研究了休闲时间体育锻炼（LTPA）和有氧运动（VO2峰值）在跑步机运动期间对689岁CE开发CE的相对贡献。在平均13.4岁的随访中，CE发生在63（9％）中。在多元COX模型中，较高的峰值VO2对CE具有保护性，无论是在男性<65年[RR = 0.53/SD]和> 65岁的男性中[RR = 0.61/SD]。相比之下，高强度LTPA（大于或等于6MET）对年龄较大但年轻的男性具有独立的保护作用。因此，增加LTPA的策略在降低年龄年龄较小的男性的CE发生率方面可能更有效。