The START trial: a proof-of-concept sedentary reduction program for prefrail older adults

项目总结 虚弱是一种综合征候群的脆弱状态，它会使65岁的成年人面临健康不良的高风险 结果。据估计，50%的美国老年人患有早衰症--临床前的虚弱程度可能更高 易受干预的努力胜过脆弱。增加体力活动是一种有希望的干预措施，可以更好地 管理/帮助扭转导致虚弱和后遗症的多系统失调。然而，启动和 对于久坐不动的老年人来说，保持习惯性的体力活动是困难的，特别是那些 健康挑战。2018年美国体力活动指南建议所有成年人进行≥150 每周锻炼几分钟，减少久坐不动的行为。然而，传统的方法增加了 体育活动对减少久坐不动的行为几乎无济于事，尤其是对老年人来说。久坐不动 行为与改善的生物和心理社会健康有关--不依赖于满足生理需求 活动指南。因此，仍然迫切需要实施和评估一种结构化的方式来减少 久坐行为是习惯性体力活动的潜在途径。客观运用小说 测量的体力活动指标，我们的研究小组已经表明，每天的久坐时间，无论是总的还是 长期积累，与脆弱联系在一起。我们的观察证据表明：1)每天，非 运动体力活动随着年龄的增长而下降，并变得更加零散(持续活动越少，时间越长 久坐的比赛)，2)较长的每日久坐时间和活动碎片化都与较高的 虚弱的发生率，以及3)久坐时间与虚弱相关的炎症标志物正相关。我们 建议进行一项先导性研究，我们随机选择60名居住在社区的老年人，让他们接受以下两项中的一项 干预措施，每种措施都旨在逐渐减少久坐时间：1)持续步行30分钟 比赛，或2)以花束的方式形成三个10分钟的步行比赛。项目目标是：a)探索 干预措施内和干预之间的有效性，以减少客观测量的久坐时间超过2 评估减少的久坐时间与i)患者报告的结果和ii)虚弱- 相关炎症标志物。主要结果是加速度计确定的久坐时间。次要的 结果包括活动碎片、患者报告的结果和炎症标志物。使用一个 跨学科指导小组，我的职业发展计划建立在我在老龄化和体能方面的专业知识上 活动流行病学精通：1)为老年人开发和实施临床试验，2) 设计改善健康行为的干预措施，3)进行与虚弱和炎症相关的研究 4)获得能力，成为一名有效的绩效指标和领导者。该项目利用了 约翰霍普金斯临床和翻译研究所(卢旺达问题国际法庭)和比查姆老年医学中心 在支持早期教师方面有很强的记录的医学。这一奖项将促进我向 一个独立的调查员，还将为R21和R01的应用提供信息性数据。

PROJECT SUMMARY Frailty is a syndromic state of vulnerability that puts adults aged ≥65 years at heightened risk of adverse health outcomes. An estimated 50% of older Americans are prefrail—a pre-clinical stage of frailty that might be more amenable to intervention efforts than frailty. Increasing physical activity is a promising intervention to better manage/help reverse the multisystem dysregulation that drives frailty and sequalae. However, initiating and maintaining habitual physical activity is difficult for sedentary older adults, particularly those encumbered by health challenges. The 2018 US Physical Activity Guidelines recommends that all adults perform ≥150 minutes/week of physical activity and reduce sedentary behaviors. Yet, traditional approaches to increase physical activity do little to address sedentary behavior reduction, especially for older adults. Lower sedentary behavior is associated with improved biological and psychosocial health—independent of meeting physical activity guidelines. Thus, there remains a critical need to implement and evaluate a structured way to reduce sedentary behavior as a potential pathway for habitual physical activity engagement. Using novel objectively measured physical activity metrics, our research group has shown that daily sedentary time, either in total or accrued in a prolonged manner, is associated with frailty. Our observation evidence shows that: 1) daily, non- exercise physical activity declines and becomes more fragmented with age (less continuous activity with longer sedentary bouts), 2) higher daily sedentary time and activity fragmentation are both associated with higher frailty incidence, and 3) sedentary time is positively associated with frailty-related markers of inflammation. We propose a pilot study in which we randomize 60 prefrail community-dwelling older adults to receive one of two interventions, each designed to gradually reduce sedentary time: 1) continuously to form a 30-minute walking bout, or 2) in a bouted manner to form three 10-minute walking bouts. Project goals are to: a) explore the effectiveness within and between interventions to decrease objectively measured sedentary time over 2 months; b) assess decreased sedentary time’s association with i) patient-reported outcomes and ii) frailty- related inflammatory markers. The primary outcome is accelerometer-determined sedentary time. Secondary outcomes include activity fragmentation, patient-reported outcomes, and inflammatory markers. With a transdisciplinary mentoring panel, my career development plan builds on my expertise in aging and physical activity epidemiology to gain proficiency in: 1) developing and implementing clinical trials for older adults, 2) designing interventions to improve health behaviors, 3) conducting frailty and inflammation related research and 4) gaining competencies to become an effective PI and leader. This project utilizes the infrastructure of the Johns Hopkins Institute for Clinical and Translational Research (ICTR) and Beacham Center for Geriatric Medicine which have strong records of supporting early-stage faculty. This award will facilitate my transition to an independent investigator and will also provide informative data for R21 and R01 applications.