Exercise training and inflammatory risk factors for disability

描述（由申请人提供）：炎症是与年龄相关的身体残疾的潜在危险因素；因此，减少老年人炎症的干预措施可能有利于延缓或治疗身体功能的丧失。来自观察性研究和小型、非受控干预研究的数据表明，体育活动可能有益于慢性炎症的治疗，但没有来自大型、长期、随机、对照运动试验的数据来证实运动训练的潜在益处。我们建议对正在进行的生活方式干预和老年人独立性（LIFE）研究进行一项辅助研究，该研究是一项四点、单盲、随机对照临床试验，在424名有身体残疾风险的老年男性和女性中进行。我们的主要目的是测量LIFE参与者在基线、随机干预后6个月和12个月的空腹血液样本中一组炎症生物标志物的血浆浓度，以检验两个主要假设：1)与非运动健康教育干预相比，12个月的运动训练干预会降低身体残疾高风险老年男性和女性的炎症生物标志物（特别是CRP和IL-6）浓度。2)12个月的身体功能测量（400米步行时间、4米步行速度和椅子上升时间）的变化与生物标志物的变化呈负相关。每组完成180人，我们将有至少80%的能力检测到36%的CRP变化和20%的IL-6变化，这是LIFE运动训练干预的结果。我们还建议进行统计分析，检验以下次要假设：1)运动干预对炎症生物标志物的影响将独立于具有身体成分测量的一部分LIFE参与者的体脂量变化；2)身体功能的基线测量将与炎症生物标志物组的因子分析得出的炎症状态变量相关；3)与不运动干预相比，运动干预将减少这种炎症状态变量。这项研究的结果将为运动训练对几种慢性炎症指标的影响提供新的知识，并将提供有价值的经验数据，说明哪种炎症标志物或炎症标志物的组合更能预测老年人身体功能低下。

DESCRIPTION (provided by applicant): Inflammation is an underlying risk factor for aging-related physical disability; therefore, interventions that reduce inflammation in the elderly may be beneficial for the delay or treatment of loss of physical function. Data from observational studies and small, uncontrolled intervention studies suggest that physical activity may be beneficial for the treatment of chronic inflammation, but there are no data from a large, long-term, randomized, controlled exercise trial to confirm this potential benefit of exercise training. We propose to conduct an ancillary study to the on-going Lifestyle Interventions and Independence for Elders (LIFE) study, which is a four-site, single-blind randomized, controlled clinical trial in 424 elderly men and women at risk for physical disability. Our primary aim is to measure plasma concentrations of a panel of inflammatory biomarkers in fasting blood samples collected from LIFE participants at baseline, and at 6-mos and 12-mos following randomization to the interventions to test two primary hypotheses that: 1) compared to a non-exercise health education intervention, a 12-month exercise training intervention will decrease concentrations of inflammatory biomarkers (specifically CRP and IL-6) in elderly men and women at high risk for physical disability, and 2) 12-mo changes in measures of physical function (400m walk time, 4m walking speed, and chair rise time) will be inversely related to changes in the biomarkers. With completion of 180 persons per group, we will have at least 80% power to detect a 36% change in CRP, and a 20% change in IL-6, as a result of the LIFE exercise training intervention. We also propose to conduct statistical analyses to test the following secondary hypotheses: 1) the effects of the exercise intervention on inflammatory biomarkers will be independent of changes in body fat mass in a subset of LIFE participants with measures of body composition, 2) baseline measures of physical function will be related to a summary inflammation status variable derived through factor analysis of the panel of inflammatory biomarkers, and 3) the exercise intervention will reduce this summary inflammatory status variable compared to the no-exercise intervention. The results of this study will provide new knowledge regarding the effects of exercise training on several indicators of chronic inflammation and will yield valuable empirical data about which individual or combination of inflammatory markers are better predictors of poor physical function in the elderly.