Nonlinear Dynamics of Fraility in Aging

衰老过程中脆弱性的非线性动力学

• 批准号: 7103357
• 负责人: LEWIS LIPSITZ
• 金额: $ 15.05万
• 依托单位: HEBREW REHABILITATION CENTER FOR AGED
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-05-01 至 2010-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7103357
• 关键词: balance; behavioral /social science research tag; cardiovascular function; cerebrovascular system; clinical research; epidemiology; frail elderly; functional ability; human old age (65+); human subject; respiratory function; statistics /biometry

DESCRIPTION (provided by applicant): Over the past 2 decades of collaborative work using the tools of nonlinear dynamics and fractal analysis, our research team has shown that aging and disease are associated with a loss of complexity in the dynamics of a variety of physiologic systems. We have proposed that this loss of complexity can lead to reduced adaptive capacity, functional decline, and frailty. Nonlinear mathematical techniques that can quantify the dynamics of physiologic systems and their interactions may, therefore, help characterize the syndrome of frailty. Accordingly, we aim: 1) To determine cross- sectionally in a representative population of elderly people aged 70 years and over, whether there is a relationship between "frailty" and loss of complexity in the dynamics of multiple physiologic systems, including cardiovascular (interbeat (RR) intervals and blood pressure (BP)), cerebrovascular (cerebral blood flow velocity (BFV)), respiratory (interbreath intervals), and balance (center-of-pressure trajectories) control systems. We will also determine whether interactions between these systems degrade in frail elderly individuals by examining the correlations, coherence, phase, and transfer function gains between the dynamic measures of interacting systems (e.g., cardiac and respiratory, or systemic BP and cerebral BFV). 2) To determine whether a loss of complexity in cardiovascular, cerebrovascular, and/or balance dynamics, is associated with an impaired ability to adapt to common physiologic stresses imposed on these systems. We will examine specifically the relationships between: a) resting BP, RR intervals, or cerebral blood flow dynamics and their responses to posture change, and b) quiet standing center-of pressure trajectories and their response to a superimposed cognitive task. 3) To determine, longitudinally over a two-year follow-up period in the same population, whether reduced complexity in the dynamics of these physiologic systems at baseline, or loss of complexity in these systems over time, is predictive of the subsequent development of frailty, its component symptoms, and/or other measures of physical and cognitive functional decline. To achieve these aims we will process and analyze physiologic data that are being gathered from a well-characterized, prospectively followed, population-based sample of 800 elderly people over age 70 who are participating in an ongoing NIA-funded Program Project Grant (the HRCA/Harvard Research Nursing Home, P01-AG004390). The experience of the research team in clinical geriatric research, physiology, dynamic systems, and biostatistics, as well as the outstanding resources of the Hebrew Rehabilitation Center and Harvard Medical School will help assure the project's success.

描述（由申请人提供）：在过去的20年中，使用非线性动力学和分形分析工具的协作工作，我们的研究团队表明，衰老和疾病与多种生理系统动力学的复杂性丧失有关。我们已经提出，这种复杂性丧失会导致适应能力，功能下降和脆弱性。因此，可以量化生理系统动力学及其相互作用的非线性数学技术可能有助于表征脆弱的综合征。 Accordingly, we aim: 1) To determine cross- sectionally in a representative population of elderly people aged 70 years and over, whether there is a relationship between "frailty" and loss of complexity in the dynamics of multiple physiologic systems, including cardiovascular (interbeat (RR) intervals and blood pressure (BP)), cerebrovascular (cerebral blood flow velocity (BFV)), respiratory (interbreath间隔）和平衡（压力中心轨迹）控制系统。我们还将通过检查相互作用系统的动态测量（例如心脏和呼吸道或全身性BP和脑BFV）之间的相关性，相干性，相位和转移功能在研究中的相关性，相干性，相位和转移功能增长来确定这些系统之间的相互作用是否降低。 2）确定心血管，脑血管和/或平衡动力学中复杂性的丧失是否与适应这些系统施加的常见生理应力的能力受损有关。我们将专门检查以下方面的关系：a）静止的BP，RR间隔或脑血流动态及其对姿势变化的反应，b）安静的站立压力轨迹及其对叠加认知任务的反应。 3）为了确定在同一人群中的两年随访期间，无论基线时这些生理系统的动力学降低还是随着时间的推移这些系统的复杂性降低，都可以预测其成分症状的随后发展，以及/或其他物理功能下降的措施。为了实现这些目标，我们将处理和分析正在从一个良好的，前瞻性的，基于人群的基于人群的样本中收集的生理数据，这些样本是70岁以上的800名老年人，他们正在进行的NIA资助计划项目Grant（HRCA/Harrca/Harvard Research Nursing Home，P01-AG004390）。研究团队在临床老年研究，生理，动态系统和生物统计学以及希伯来康复中心和哈佛医学院的杰出资源方面的经验将有助于确保该项目的成功。