CARDIOVASCULAR VULNERABILITY TO PARTICULATE EXPOSURE

颗粒物暴露导致的心血管脆弱性

• 批准号: 6502519
• 负责人: DIANE R GOLD
• 金额: $ 19.62万
• 依托单位: HARVARD MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-01 至 2002-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6502519
• 关键词: aerobic exercise; air pollution; air sampling /monitoring; arrhythmia; blood pressure; body physical characteristic; carbon monoxide; cardiovascular disorder epidemiology; clinical research; disease /disorder proneness /risk; electrocardiography; hazardous substances; heart conduction system; heart rate; human old age (65+); human subject; humidity; myocardial infarction; outcomes research; oximetry; particle; seasons; self care; smoking; temperature

Epidemiologic associations between particulate air pollution and cardiovascular hospitalization and mortality have been found, but little is understood about the physiologic mechanisms by which humans respond to particulate exposure. Canines respond to concentrated fly-ash and/or fine particles with ECG repolarization abnormalities including ST segment abnormalities, T-wave alternans (an index of susceptibility to sudden death), and changes typical of both hyperadrenergic activity and vagally mediated effects, depending on the underlying status of the dogs. In susceptible adults we propose to examine whether particle exposure results in similar changes, particularly in measures of autonomic function, myocardial conductance, repolarization, and irritability. Outdoor and indoor PM2~5, PM10, CO, O3, NO2, 502 and temperature will be considered as exposures. A Boston community-based panel of 50 active adults 60-90 yr of age will be recruited and evaluated over two 3-month summer periods; this panel study will be repeated in a higher pollution community in two subsequent summers. Once per week for l2 weeks the participants will receive supine and upright blood pressure, oximetry and continuous ECG Holter monitoring for a 25 minute period (5 minutes of rest supine, 5 minutes of standing upright, 5 minutes of exercise, 5 minutes of recovery and 5 minutes of slow breathing.) Electrophysiologic outcomes will include ECG repolarization abnormalities, ventricular premature beats, measures of heart rate variability; PR and QT intervals. Modification or response by underlying disease and medication will be considered. A second study of >800 outpatients will assess the associations between particulate exposure and cardiopulmonary exercise data routinely collected during repeated exercise in two Boston cardiac and pulmonary rehabilitation units. These will enable us to assess whether particulate exposure is associated with physiologic changes predictive of cardiovascular vulnerability and sudden death in active humans who are susceptible on the basis of age or disease.

人们已经发现颗粒物空气污染与心血管住院和死亡率之间存在流行病学关联，但人们对人类对颗粒物暴露的反应的生理机制知之甚少。犬科动物对浓缩飞灰和/或细颗粒的反应会出现心电图复极异常，包括 ST 段异常、T 波交替（猝死易感性指数），以及肾上腺素能亢进活动和迷走神经介导效应的典型变化，具体取决于狗的基本状况。在易受影响的成年人中，我们建议检查颗粒暴露是否会导致类似的变化，特别是在自主功能、心肌电导、复极化和烦躁性的测量方面。室外和室内PM2~5、PM10、CO、O3、NO2、502和温度将被视为暴露。将招募一个由 50 名 60-90 岁活跃成年人组成的波士顿社区小组，并在两个为期 3 个月的夏季期间进行评估；这项小组研究将在随后的两个夏天在污染较高的社区重复进行。每周一次，持续 12 周，参与者将接受仰卧和直立血压、血氧测定和连续心电图动态心电图监测 25 分钟（5 分钟仰卧休息、5 分钟直立站立、5 分钟锻炼、5 分钟恢复和5 分钟缓慢呼吸。）电生理结果将包括心电图复极异常、室性早搏、心率变异性测量； PR 和 QT 间期。将考虑潜在疾病和药物的改变或反应。另一项针对超过 800 名门诊患者的研究将评估颗粒物暴露与在波士顿两个心肺康复中心重复运动期间常规收集的心肺运动数据之间的关联。这些将使我们能够评估颗粒物暴露是否与因年龄或疾病而易受影响的活跃人群的生理变化有关，这些生理变化可预测心血管脆弱性和猝死。