Exercise training and inflammatory risk factors for disability

描述(申请人提供)：炎症是与衰老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，体育锻炼可能对治疗慢性炎症有益，但还没有一项长期、随机、受控的大型运动试验的数据来证实运动训练的这种潜在好处。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，这是一项四点、单盲、随机、对照的临床试验，涉及424名有身体残疾风险的老年男性和女性。我们的主要目标是测量在基线和随机化干预措施后的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，以检验两个基本假设：1)与非运动健康教育干预相比，12个月的运动训练干预将降低肢体残疾高危老年男性和女性的炎症生物标志物(特别是CRP和IL-6)的浓度；2)身体机能指标(400米步行时间、4米步行速度和椅子起立时间)12个月的变化将与生物标志物的变化成反比。随着每组180人的完成，我们将有至少80%的能力来检测由于生活锻炼干预而导致的CRP和IL-6的36%和20%的变化。我们还建议进行统计分析，以检验以下二级假设：1)运动干预对炎症生物标记物的影响将独立于使用身体成分测量的生活参与者子集中体脂质量的变化，2)身体功能的基线测量将与通过对炎症生物标记物小组的因子分析而得出的概要炎症状态变量有关，以及3)与非运动干预相比，运动干预将降低该概要炎症状态变量。这项研究的结果将为运动训练对慢性炎症的几个指标的影响提供新的知识，并将产生有价值的经验数据，即哪些单独的或组合的炎症指标更好地预测老年人的身体功能不良。

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.