ASSESSING CARDIOVASCULAR REACTIVITY IN HUMAN POPULATIONS

本拟议项目的主要目的是开发一个 评估心血管反应性的综合方案 压力源，用于流行病学和临床调查 反应性和心血管疾病。 在 为了设计一个有效的反应协议，我们打算建立 并评估测量基线值的程序， 适当的挑战任务，测量 适当的亚组和相关的心血管指标 在实验室中获得的， 自然环境。 已经探索了一个大的 反应性任务的数量与主要人口亚组，我们 打算进行一项大规模研究， 检查足够数量的主题，以满足以下目标 RFA。 因此，拟定的研究将招募240例受试者， 2（男性，女性）X 2（黑人，白色）X 2（25-44岁，55-64岁） X 2（迈阿密，达勒姆）设计。 受试者将在 广泛的社会经济地位。 每例受试者将 计划进行3次实验室检查，每次不超过60分钟。 第1次和第2次会议将间隔2周;第3次会议将持续6个月 后 在这些实验室会议期间，受试者将受到 前额冷加压刺激，视频游戏和 评价性言语应激源 选择这些任务是因为 易于给药，能够引发一系列生理学反应， 健康人的反应，能够区分人群 亚组，并且似乎对同一个体是可重复的 and across横过different不同sites地点. 无创心血管措施 评估内容包括心率、心输出量、外周血 阻力;石楠指数;射血前期;左心室 射血期;收缩期、舒张期和平均动脉血 压力（BP）。 在每个实验室反应的同一天 会话中，受试者将佩戴动态阻抗， 心电图（ECG）监测仪在工作和家庭。 的 第二天，受试者将佩戴动态血压监测仪， 工作和家里。 将根据稳定性分析数据， 基线值，实验室反应性差异 组，任务之间反应模式的差异， 跨会话任务响应的可靠性， 反应性作为个体差异变量，以及 实验室反应性对心血管疾病的普遍性 在更自然的环境中观察功能。 为了 为实现这些目标，将制定改进的程序， 监测阻抗心电图和ECG活动， 实验室以及更自然的设置。

The major purpose of this proposed project shall be to develop a comprehensive protocol for assessing cardiovascular reactivity to stressors, for use in epidemiological and clinical investigations of reactivity and cardiovascular diseases in healthy populations. In order to devise a valid reactivity protocol we intend to establish and evaluate procedures for measuring baseline values, providing appropriate challenge tasks, measuring physiological responses in appropriate subgroups, and relating cardiovascular measures obtained in the laboratory to those obtained under more naturalistic circumstances. Having already explored a large number of reactivity tasks with major population subgroups, we intend to proceed with a single large-scale study in order to examine a sufficient number of subjects to meet the objectives of the RFA. Thus, the proposed study will enroll 240 subjects into a 2 (male, female) X 2 (black, white) X 2 (25-44 years, 55-64 years) X 2 (Miami, Durham) design. Subjects will be compared across a broad range of socioeconomic statuses. Each subject will be scheduled for 3 laboratory sessions lasting less than 60 min each. Sessions 1 and 2 will be 2 weeks apart; session 3 will be 6 months later. During these laboratory sessions subjects will be subjected to a forehead cold pressor stimulus, a video game and an evaluative speech stressor. The tasks were chosen because they are easily administered, capable of eliciting a range of physiologic responses in healthy people, capable of discriminating population subgroups, and appear to be reproducible for the same individual and across different sites. Noninvasive cardiovascular measures to be assessed will include heart rate; cardiac output; peripheral resistance; Heather Index; pre-ejection period; left ventricular ejection period; and systolic, diastolic and mean arterial blood pressure (BP). On the same day as each laboratory reactivity session, subjects will wear an ambulatory impedance and electrocardiogram (ECG) monitor at work and at home. The following day the subject will wear an ambulatory BP monitor at work and at home. Data will be analyzed in terms of stability of baseline values, differences in laboratory reactivity between groups, differences in reactivity patterns between tasks, reliability of responses to tasks across sessions, differences in reactivity as an individual difference variable, and generalizability of reactivity in the laboratory to cardiovascular function observed in more naturalistic settings. In order to accomplish these goals improved procedures will be developed for monitoring impedance cardiographic and ECG activity both in the laboratory as well as in more naturalistic settings.