Evaluating Standing as a Health Behavior to Promote Cardiovascular Risk Reduction in African Americans

美国成年人每天久坐约11 - 12小时-这大大增加了心血管疾病（CVD）， 死亡风险。美国人的体育活动指南已经扩展到促进适度- 积极的身体活动，现在也提倡减少久坐的时间。因此，有强大的 有兴趣阐明简单，具有成本效益的方法，以减少久坐时间。大众媒体和 寻求利用健康趋势的公司已经延续了这样一种观念，即仅仅站在原地就是 一个健康的替代坐着。因此，站立式办公桌和坐立式办公桌是增长最快的 美国工作场所的员工福利。然而，缺乏证据证明健康益处 站着。因此，尽管公众认为站立是一种健康的选择， 体育活动指南，并提出了关注，站立可能比坐着更有害。的目标 拟议的研究是全面评估声称的益处（心脏代谢）和风险（血管 下肢损伤，肌肉骨骼疼痛），可能与站立及其累积模式 美国最高风险群体--生活在中风地带的非洲裔美国人。之间的潜在关联 客观测量的站立时间和复合CVD风险评分（包括葡萄糖， 甘油三酯、胆固醇、血压、腰围）进行评价（目的1）。多重小说 将研究站立模式变量（例如站立发作的分布、长度和规律性）， 确定站立的哪些方面与CVD风险评分的2年变化最相关（目标2）。状态 最先进的分析技术将被用来评估是否重新分配时间从久坐到站立将产生 CVD风险评分降低（次要目的）。站立时间/模式与 2-踝臂指数（ABI，外周血管疾病的指数）和肌肉骨骼的年变化 疼痛症状和站立的横断面/前瞻性预测因子也将进行检查（探索性 目的）。为了实现我们的研究目标，我们将利用杰克逊心脏研究（JHS）的基础设施， 非裔美国人队列研究第四次JHS考试计划于2020 - 2022年进行， 将包括CVD风险因素的评估。对于这项辅助研究，我们建议增加一个7天加速计 协议（姿势检测），ABI评估和问卷调查，这项考试的1,250名参与者。我们 此外，建议2年后进行随访，以重新评估这些措施和CVD风险因素。结果 将（1）告知与地位和健康结果有关的可能因果关系，（2）确定 （3）为未来的试验建立终点， 站立，以及（4）确定站立的预测因素，可以作为干预目标。我们把这个项目看作是 关键的下一步，这将为未来试验的成功提供重要的基础证据， 针对非裔美国人和其他人群久坐行为的公共卫生工作。

US adults are sedentary for ~11-12 h/day - which greatly increases cardiovascular disease (CVD) and mortality risk. The Physical Activity Guidelines for Americans have expanded beyond promoting moderate- vigorous physical activity and now also advocate for reductions in sedentary time. Accordingly, there is strong interest in elucidating simple, cost-effective methods to reduce sedentary time. The popular press and corporations seeking to capitalize on health trends have perpetuated the notion that simply standing in place is a healthful alternative to sitting. Consequently, standing and sit-to-stand desks are the fastest growing employee benefit in US workplaces. However, there is a paucity of evidence documenting the health benefits of standing. As such, despite public perception that standing is a healthful alternative, it remains absent from physical activity guidelines, with concerns raised that standing could be more harmful then sitting. The goal of the proposed study is to comprehensively evaluate purported benefits (cardiometabolic) and risks (vascular damage to lower limbs, musculoskeletal pain) that may be incurred with standing and its accrual pattern in the highest risk group in the US - African Americans living in the stroke belt. The prospective association between objectively-measured standing time and the 2-year change in a composite CVD risk score (comprising glucose, triglycerides, cholesterol, blood pressure, waist circumference) will be evaluated (Aim 1). Multiple novel standing pattern variables (e.g. distribution, length, and regularity of standing bouts) will be investigated to identify which aspects of standing are most associated with the 2-year change in CVD risk score (Aim 2). State of the art analytic techniques will be used to evaluate if reallocating time from sedentary to standing would yield CVD risk score reductions (Secondary Aim). Prospective associations between standing time/patterns and the 2-year change in the ankle-brachial index (ABI, an index of peripheral vascular disease) and musculoskeletal pain symptoms, and the cross-sectional/prospective predictors of standing will also be examined (Exploratory Aims). To address our study aims, we will leverage the infrastructure of the Jackson Heart Study (JHS), an exclusively African American cohort study. A fourth JHS exam is scheduled to be conducted in 2020-2022 and will include assessment of CVD risk factors. For this ancillary study, we propose to add a 7-day accelerometer protocol (with posture detection), ABI assessment, and questionnaires to this exam for 1,250 participants. We furthermore propose a follow-up visit 2 years later to re-assess these measures and CVD risk factors. Findings will (1) inform probable cause and effect associations with respect to standing and health outcomes, (2) identify optimal patterns of standing that should be promoted, (3) establish endpoints for future trials promoting standing, and (4) identify predictors of standing that can serve as intervention targets. We view this project as a critical next step that will provide foundational evidence important for success of future trials and ultimately public health efforts targeting sedentary behavior in African Americans and other population groups.