Effects of Deployment Exposures on Cardiopulmonary and Autonomic Function

描述(由申请人提供)： 项目摘要/摘要：有明确证据表明，部署在持久行动和伊拉克自由行动和新黎明行动(OEF/OIF/OND)的退伍军人暴露在超过环境、职业和军事暴露准则的高水平颗粒物(PM)中。PM暴露被认为是心血管发病率和死亡率的危险因素，并可能增加和加剧呼吸道疾病的风险。回顾的流行病学表明，新报告的OEF/OIF/OND退伍军人的呼吸道症状发病率很高，这严重影响了他们的部署职责，包括他们的体力消耗能力。尽管有这些回溯性数据和有限的空气采样报告，但缺乏前瞻性研究。我们的试点研究将采用综合方法评估OEF/OIF/OND退伍军人的心肺和自主神经功能，并与从未部署到该地区的退伍军人进行比较。为了评估心肺功能，每个退伍军人都将接受运动挑战，包括运动前和运动后(运动后5、10、15、20和30分钟)的肺活量测定。锻炼将以跑步机为基础，参与者将努力在目标通风和心率下保持6-8分钟的锻炼。对于肺活量测试， 退伍军人将被要求在每个时间点进行最大限度的用力呼气动作。肺活量测定也将在单独的一天重复，以包括相同的最大用力呼气动作，但将在支气管扩张剂之前和之后进行评估。由于我们预计交感迷走神经平衡会改变，我们将评估在起搏呼吸过程中心率变异性的几个指标。此外，我们还将量化脑血流量、血压、心率和通气量，以响应Valsalva动作和体位变化(即坐立)。这一综合评估将提供自主神经系统调节心血管功能的情况，而心血管功能依赖于精确的反射调节。这些评估可能提供对认可症状背后的病理生理机制的洞察，并可能为减轻长期不良后果(如肺部和心血管疾病)提供干预点。从这一试点项目获得的数据将对心肺功能损害的程度和严重程度产生重要的洞察力--这些数据随后可用于指导康复。此外，自主测试的结果将具有类似的疗效 检测亚临床或显性生理变化的存在。通过早期识别，可以实施治疗方案(例如运动疗法、药物)以增强自主神经功能，目的是帮助缓解症状和降低慢性病风险。 公共卫生相关性： 项目简介：在部署到持久行动和伊拉克自由和新黎明行动(OEF/OIF/OND)后，退伍军人报告呼吸问题、运动困难和其他症状。这些症状可能与部署暴露有关，如区域灰尘和沙子、焚烧垃圾产生的烟雾和当地工业。研究报告了糟糕的空气质量，但人们对暴露在这种污染空气中对退伍军人短期和长期健康的影响知之甚少。我们将确定与部署相关的暴露是否影响了这些退伍军人的呼吸和神经系统功能-这些数据随后可能被用于指导康复。最终，我们的长期目标是早期识别和循证治疗，以防止这组OEF/OIF/OND退伍军人发生慢性呼吸系统疾病。

DESCRIPTION (provided by applicant): Project Summary/Abstract: Evidence is clear that Veterans deployed to Operations Enduring and Iraqi Freedom and Operation New Dawn (OEF/OIF/OND) have been exposed to high levels of particulate matter (PM) that exceeded environmental, occupational and military exposure guidelines. PM exposure is acknowledged as a risk factor for cardiovascular morbidity and mortality, and can increase the risk of and exacerbate airway disease. The reviewed epidemiology indicates a high prevalence of newly reported respiratory symptoms in OEF/OIF/OND Veterans that has significantly affected their deployment duties, including their physical exertion capability. Despite these retrospective data and limited air sampling reports, prospective studies are absent. Our pilot study will take an integrative approach to evaluate cardiorespiratory and autonomic function in OEF/OIF/OND Veterans as compared to Veterans never deployed to the region. To evaluate cardiopulmonary function, each Veteran will undergo an exercise challenge which consists of spirometry before and then serially after exercise (5, 10, 15, 20, and 30 min post-exercise). Exercise will be treadmill-based and participants will try to maintain 6 - 8 minutes of exercise at a target ventilation and heart rate. For spirometric testing, Veterans will be asked to perform a maximal forced expiratory maneuver at each time point. Spirometry will also be repeated on separate day to include the same maximal forced expiratory maneuver, but will be assessed before and after a bronchodilator. As we anticipate altered sympathovagal balance, we will evaluate several indices of heart rate variability during paced breathing. In addition, we will quantify cerebral blood flow, blood pressure, heart rate and ventilation in response to a Valsalva maneuver and postural change (i.e. sit-to-stand). This integrative assessment will provide an indication of how well the autonomic system regulates cardiovascular function, which is dependent on precise reflex regulation. These assessments may provide insight on the pathophysiological mechanisms that underlie endorsed symptoms, and may provide intervention points for attenuating long-term adverse outcomes such as pulmonary and cardiovascular disease. Data derived from this pilot project will yield important insight on the extent and severity of cardiorespiratory impairment - data that may then be used to guide rehabilitation. In addition, results from autonomic testing will be of similar efficacy in detecting the presence of subclinical or overt physiological changes. Through early identification, treatment options (e.g. exercise therapy, pharmaceutical) may be implemented to enhance autonomic function, with the goal of helping to alleviate symptoms and reduce chronic disease risk. PUBLIC HEALTH RELEVANCE: Project Narrative: Following deployment to Operations Enduring and Iraqi Freedom and Operation New Dawn (OEF/OIF/OND), Veterans report breathing problems, difficulty exercising and other symptoms. These symptoms are likely related to deployment exposures, such as regional dust and sand, smoke from burning trash, and local industry. Studies have reported poor air quality, but very little is known about the effect that exposure to this polluted air may have on Veterans' short- and long-term health. We will determine whether deployment-related exposures have affected respiratory and nervous system function in these Veterans - data that may then be used to guide rehabilitation. Ultimately, our long-term goal is early identification and evidence-based therapy to prevent the development of chronic respiratory conditions in this group of OEF/OIF/OND Veterans.