Effects of Walking in Greenspace and the Built Environment in Adults with Prediabetes: A Randomized Crossover Trial

项目摘要：鉴于糖尿病对健康和经济造成的严重不利后果， 预防糖尿病前期(美国成年人的患病率为38%)发展为2型糖尿病(T2D)是一项重要的工作 公共卫生目标。环境在决定T2D的风险方面起着关键作用。城镇化一直是 与增加的心理社会压力和不利的健康后果有关。应激反应引起荷尔蒙 导致胰岛素抵抗、高血糖、炎症、氧化应激和肥胖的变化。增加了 暴露在空气污染中与患糖尿病和心血管疾病的风险更高有关。 “绿地”被定义为具有主要自然主义元素(如树木、草地、 水景等)。之前对成年人的研究支持这样一种假设，即暴露在绿色空间中(绿色) 与城市建成(灰色)环境相比，可能有几个健康益处。这些好处可能包括更好的 自主神经功能通过改善心率变异性(HRV)、减少焦虑/压力和 加强心理恢复，绿色空间还起到缓冲空气污染的作用。走路是最重要的 这是一种常见的中等强度体力活动，对血糖控制有好处。 初步研究表明，散步和接触绿色空间可能共同作用于改善健康 结果。然而，除了我们的初步研究外，还没有进行严格的实验研究来 与城市灰色空间相比，研究有规律的步行与接触城市绿地之间的相互作用， 以增进健康。需要这些研究来调查新的和高度概括性的绿色战略 运动“，能够在人口一级实施，以减轻疾病负担。因此，我们 将进行机械随机交叉试验，以比较生理、心理、空气等方面的差异 城市绿色和灰色步行干预措施的污染和心脏代谢风险测量 糖尿病前期成人的环境。这项多点试验将包括大都市地区的180名受试者 明尼阿波利斯/明尼苏达州圣保罗和伊利诺伊州芝加哥将在城市绿地和城市完成步行干预 灰色环境，参与者在每个环境中每周步行150分钟，持续6周， 隔着5周的洗礼。具体目标：目标1：测量和比较以下人群的心理社会压力 绿色和灰色的行走。目标2：测量并比较格林和格林在六周内的生理压力 灰色的行走。目标3：使用个人空气测量个人对周围颗粒物的实时暴露 在绿色和灰色环境中行走时，带有GPS跟踪的污染监测器。目标4：衡量个人 心脏代谢性疾病风险评分(血糖、胰岛素、血脂、收缩压和腰围指数) 在格林和格雷步行6周前和之后的炎症因子。目标5(探索性)：检查 无论生理、心理和空气污染措施是否调解了绿色与 使用基于回归的中介模型对心脏代谢风险和炎症进行灰色行走。

PROJECT SUMMARY: Given the substantial adverse health and economic consequences of diabetes, preventing progression of prediabetes (prevalence of 38% in U.S. adults) to type 2 diabetes (T2D) is a major public health goal. The environment plays a critical role in determining risk for T2D. Urbanization has been associated with increased psychosocial stress and adverse health outcomes. Stress responses cause hormonal changes that lead to insulin resistance, hyperglycemia, inflammation, oxidative stress, and obesity. Increased exposure to air pollution has been associated with higher risk of diabetes and cardiovascular disease. ‘Greenspace’ is defined as publicly accessible areas with predominant naturalistic elements (e.g., trees, grass, water features, etc.). Previous studies in adults support the hypothesis that exposure to Greenspace (‘Green’) may have several health benefits relative to urban built (‘Gray’) environments. These benefits may include better autonomic functioning as assessed by improved heart rate variability (HRV), reductions in anxiety/stress, and enhanced psychological restoration, with Greenspace also serving to buffer air pollution. Walking is the most common form of moderate-intensity physical activity and has a beneficial influence on blood glucose control. Preliminary studies have suggested walking and exposure to Greenspace may act together to improve health outcomes. Yet, aside from our preliminary studies, rigorous experimental studies have not been conducted to examine how regular walking may interact with exposure to urban Greenspace, compared to urban Grayspace, to improve health. These studies are needed to investigate novel and highly generalizable strategies for “Green exercise”, capable of being implemented at the population-level to reduce the burden of disease. Therefore, we will conduct a mechanistic randomized crossover trial to compare differences in physiological, psychological, air pollution, and cardiometabolic risk measures between walking interventions completed in urban Green and Gray environments in adults with prediabetes. This multisite trial will include 180 individuals within metropolitan areas of Minneapolis/St. Paul, MN and Chicago, IL. Walking interventions will be completed in urban Green and urban Gray environments, with participants engaging in 150 minutes/week of walking for 6 weeks in each environment, separated by a 5-week washout. Specific Aims: Aim 1: Measure and compare psychosocial stress between Green and Gray walking. Aim 2: Measure and compare physiological stress over six weeks between Green and Gray walking. Aim 3: Measure real-time individual exposure to ambient particulate matter using personal air pollution monitors with GPS tracking while walking in Green and Gray environments. Aim 4: Measure individual cardiometabolic disease risk scores (index of blood glucose, insulin, lipids, systolic blood pressure, and waist) and inflammatory factors before and after 6 weeks of Green and Gray walking. Aim 5 (exploratory): Examine whether physiological, psychological, and air pollution measures mediate the differential impact of Green vs. Gray walking on cardiometabolic risk and inflammation using regression-based mediation models.