Effects of Deployment Exposures on Cardiopulmonary and Autonomic Function

Overview

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 may be 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. Investigators 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, the investigators' long-term goal is to prevent the development of chronic respiratory conditions in this group of OEF/OIF/OND Veterans.

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 lacking. This pilot study will 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 a standardized exercise challenge and bronchodilator spirometry. To evaluate autonomic nervous system function, investigators will examine indices of heart rate variability and cardiovascular reflex regulation (e.g. baroreflex sensitivity and cerebral autoregulation) during a variety of tasks. Data derived from this pilot project will yield important insight on the extent and severity of cardiorespiratory and/or autonomic impairments - data that may provide intervention points for attenuating long-term adverse outcomes such as pulmonary and cardiovascular disease. Through early identification, treatment options (e.g. exercise therapy, pharmaceutical) may be implemented to enhance physiological function, with the goal of helping to alleviate symptoms and reduce chronic disease risk.