Sitting Interruption and Whole-body Cardiovascular Health: Linking Physiological Responses to Risk Behaviors

摘要 久坐行为(SB)是生物学上不同的危险因素，但对心血管疾病(CVD)的研究较少。 国家和国际机构推测，总体和剂量反应的证据水平 SB和CVD死亡率之间的关联是中等-强烈的。这些机构不提供具体的 对拆分某人的建议，尽管确实呼吁研究界促进政策 通过建立生物学可信性，确定Sb替代策略的最佳剂量， 并进行随机临床试验，以测试这些策略的有效性。我们的目标是找出 机制知情的、基于社会生态的SB替代建议，以降低心血管疾病风险。 目标1A将确定一种可行的Sb替代策略，以防止以下药物的不良心血管反应 延长某人的时间心血管不良反应将使用主动脉僵硬(AS)来衡量，a 预测未来心血管疾病的非侵入性测试。为了实现这一目标，在56个中年人(36-55岁) 参与者，我们将测量以下4小时内的主动脉AS和相关的机械反应：(I) 某人每小时步行休息一次；(Ii)某人每小时站立休息一次；(Iii)某人每小时休息两次 (交替步行5分钟和站立15分钟)；和(Iv)没有休息的人(对照)。这些策略都是经过选择的 基于我们小组之前的大量工作，因为它们是可行的，这是这一点的关键组成部分 求婚。只有当人们愿意坚持未来的SB时，SB减少策略才会降低心血管疾病的风险 换人建议。为了增加可行性和长期坚持的可能性，目标1B将 使用社会生态学模型评估某人的决定因素。这承认了行为的改变很有可能 如果物质和社会文化环境不支持行为改变，就会受到限制。要完成 目的1B，将采用归纳-演绎相结合的定性方法。完成目标1A的参与者 将参加6个焦点小组之一(6-8人/组)。目标2A将测试以下项目的可行性 通过个性化的单臂12周干预在现实世界中实施战略(n=40，36- 年)。来自目标1的机械性(目标1A)和定性(目标1B)数据将指导干预设计。 我们将测试以下可行性领域：需求、可接受性、实现、实用性、集成性、 和有限的疗效。最后，目标2B将调查干预的哪些组成部分有效，哪些有效 组件不起作用。所有完成目标2A的参与者将被要求完成问卷调查 与我们的行为模式有关，以及参加焦点小组。焦点小组将用于添加 与量化可行性数据相关的上下文。具体地说，我们将解决可接受性、采用率、适当性、 可持续性，以及感知到的社会生态决定因素。至关重要的是，这项提议的结果将是 有助于促进后续临床试验的设计，以测试一种机制-知情但可行 减少SB的干预，并通过这样做直接支持SB政策的发展。

ABSTRACT Sedentary behaviors (SB) are biologically distinct but understudied cardiovascular disease (CVD) risk factors. National and international agencies have surmised that the level of evidence for an overall and dose-response association between SB and CVD mortality is moderate-strong. These agencies do not provide specific recommendations for breaking-up SB, though do call on the research community to facilitate policy development by establishing biological plausibility, identifying the optimal dose for SB substitution strategies, and conducting randomized clinical trials to test the efficacy of these strategies. Our goal is to identify mechanism-informed, socioecological-based SB substitution recommendations to mitigate CVD risk. Aim 1A will identify a feasible SB substitution strategy to prevent the adverse cardiovascular responses to prolonged SB. Adverse cardiovascular responses will be measured using aortic arterial stiffness (AS), a noninvasive test that predicts future CVD. To accomplish this aim, in 56 middle-aged (36-55 years) participants, we will measure aortic AS and associated mechanistic responses to the following over 4 hours: (i) SB with once/hour 5 min walk break; (ii) SB with once/hour 15 min stand break; (iii) SB with twice/hour breaks (alternating 5 min walk and 15 min stand); and (iv) SB with no breaks (control). These strategies were selected based on extensive prior work by our group, and because they are feasible, which is a key component of this proposal. SB reduction strategies will only decrease CVD risk if people are willing to adhere to future SB substitution recommendations. To increase the likelihood of feasibility and long-term adherence, Aim 1B will evaluate the determinants of SB using a socioecological model. This recognizes that behavior change is likely to be limited if the physical and sociocultural environments do not support the behavior change. To accomplish Aim 1B, a combined inductive-deductive qualitative approach will be used. Participants who complete Aim 1A will be participate in one of 6 focus groups (6-8 participants/group). Aim 2A will then test the feasibility of implementing the strategy in the real-world via an individualized single-arm 12-week intervention (n=40, 36-64 years). The mechanistic (Aim 1A) and qualitative (Aim 1B) data from Aim 1 will guide the intervention design. We will test the following feasibility domains: demand, acceptability, implementation, practicality, integration, and limited-efficacy. Lastly, Aim 2B will investigate which components of the intervention worked and which components did not work. All participants who complete Aim 2A will be asked to complete questionnaires pertaining to our behavioral model as well as participate in a focus group. The focus groups will be used to add context to the quantitative feasibility data. Specifically, we will address acceptability, adoption, appropriateness, sustainability, and the perceived socioecological determinants. Crucially, the outcomes from this proposal will be instrumental in facilitating the design of a subsequent clinical trial to test a mechanism-informed yet feasible SB reduction intervention, and in doing so directly support the development of SB policy.