Slowing Atherothrombosis Progression through Indoor Air Filtration: A Crossover Trial in Hispanic and non-Hispanic Adults with Ischemic Heart Disease History

摘要 心血管疾病（CVD）是美国的主要死亡原因。日益增加 认识到细颗粒物污染（PM2.5）对CVD发病率和死亡率的重要贡献。 越来越多的证据表明，使用室内空气过滤可以将PM2.5暴露时间从几天减少到几周 导致急性动脉粥样硬化血栓形成生物标志物的改善。然而，没有试验评估这些 短期效果持续或随着延长的过滤而进一步改善。拟议的研究是最长的 在住宅中使用低成本空气净化器对改善 动脉粥样硬化血栓形成的进展在脆弱的个人。这项研究将检查动脉粥样硬化血栓形成反应， 在男性或女性以及西班牙裔或非西班牙裔参与者的四个亚组中进行HEPA过滤。 我们将利用洛杉矶不同的人口来研究室内PM2.5过滤对这两个方面的影响。 动脉粥样硬化血栓形成生物标志物（包括动脉僵硬度、血压、靶向 促炎和促血栓形成标志物，和新的蛋白质组标志物，以及CVD风险评分。重点 在随时间变化的斜率上是新颖的，并将提供对未来CVD事件和死亡率的更好预测 生物标志物水平的变化在以前的研究中评估。我们有一支经验丰富的调查团队， 南加州大学（USC）和杜克大学，并将利用丰富的患者资源，从 南加州大学KECK电子病历和相关的人口普查跟踪PM2.5数据，以招募100名参与者， 65-84岁非吸烟者，有缺血性心脏病史（临床稳定至少6个月）， 在过去几年中，居住在人口普查轨道上的环境PM2.5暴露较高。参与者将被封锁- 随机分配至两个干预组（HEPA或假过滤，各持续9个月），并交叉至 另一个干预组在3个月的洗脱期后。这种设计使我们能够进行两次干预 在连续两年的同一个日历月内。期间将进行三次家访， 建立和校准空气监测器、测量健康结果和收集生物标本干预部门。 将通过在线问卷收集生活方式和健康协变量。交叉设计和时机- 控制干预将减少混杂因素的影响，因为参与者作为自己的 在人与人之间的比较中。测量室内外PM2.5和混合污染物;以及 气象数据和野火事件将在整个试验过程中记录。这些协变量将是 在统计分析中进行了调整。我们的目标符合NOT-HL-20-788要求可行性试验的目标， 研究便携式空气净化器对减少PM2.5暴露和CVD生物标志物的影响，包括新的 组学标记。拟议研究的结果将提供有效性和可行性数据，以支持未来的 全国性或多中心试验，以进一步研究空气过滤对不良CVD事件发生率的影响， mortality.

ABSTRACT Cardiovascular disease (CVD) is the leading cause of death in the US. There has been an increasing recognition of the important contribution of fine particulate pollution (PM2.5) to CVD morbidity and mortality. Mounting evidence suggests that the use of indoor air filtration to reduce PM2.5 exposure from days to weeks leads to improvement in acute atherothrombosis biomarkers. However, no trials have assessed whether these short-term effects are sustained or further improved with prolonged filtration. The proposed study is the longest intervention trial investigating the effect of using low-cost air purifiers in residences on ameliorating atherothrombosis progressions in vulnerable individuals. The study will examine atherothrombosis responses to HEPA filtration across and within four subgroups of male or female and Hispanic or non-Hispanic participants. We will leverage the diverse population in Los Angeles to investigate the effect of indoor PM2.5 filtration on both levels and slopes of change in atherothrombosis biomarkers including arterial stiffness, blood pressure, targeted proinflammatory and prothrombotic markers, and novel proteomic makers, as well as CVD risk score. The focus on the slopes of change over time is novel and will provide better prediction of future CVD events and mortality than biomarker level changes assessed in previous studies. We have an experienced team of investigators at the University of Southern California (USC) and Duke University and will leverage the rich patient resource from the USC KECK electronic medical records and the linked census-track PM2.5 data to enroll 100 participants of 65-84 years old non-smokers with a history of ischemic heart disease (clinically stable for at least 6 months) who have lived in the census track with higher ambient PM2.5 exposure in the past years. Participants will be block- randomized to two intervention arms (HEPA or sham filtrations, each of 9-month duration) and crossed over to the other intervention arm after a 3-month washout period. This design allows us to conduct the two intervention arms in the same calendar months of two consecutive years. Three home visits will be conducted during each intervention arm to set-up and calibrate air monitors, measure health outcomes, and collect biospecimens. Lifestyle and health covariates will be collected through online questionnaires. The crossover design and timing- controlled interventions will reduce the influence of confounding factors since participants serve as their own controls in the within-person comparison. Indoor and outdoor PM2.5 and co-pollutants will be measured; and meteorological data as well as wildfire events will be recorded throughout the trial. These covariates will be adjusted for in the statistical analyses. Our aims match the goal of NOT-HL-20-788 calling feasibility trials to investigate the effects of portable air cleaners on reducing PM2.5 exposure and CVD biomarkers including novel omics markers. Findings of the proposed study will provide the efficacy and feasibility data to support future nationwide or multi-center trials to further investigate the air filtration effect on adverse CVD event incidence and mortality.