Effects of Deployment Exposures on Cardiopulmonary and Autonomic Function

Study Overview
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Brief Summary
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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.

Detailed Description
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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.

Official Title
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Effects of Deployment Exposures on Cardiopulmonary and Autonomic Function

Conditions
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Abnormality, Respiratory System, Autonomic Nervous System

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Male and female Veterans between 18 - 55 years of age will be identified and screened for this study. Two study cohorts will be recruited and attempts will be made to match group composition on age, body mass index and smoking history. Veterans assigned to the Exposed group must have been deployed to OEF/OIF for a minimum of 90 consecutive days. The Control group will consist of Veterans never deployed to Southwest Asia (i.e. OEF/OIF, Persian Gulf War) but were deployed during the same time period. Each Veteran will complete a detailed exposure history questionnaire to confirm and support their group assignment. Exclusion Criteria: Participants must not meet any of the contraindications to exercise testing as described in the joint statement from the American College of Cardiology and American Heart Association. Also, individuals with history of any of the following will also be excluded: asthma (pre-military) cardiovascular disease neurological impairment/disorder pregnant uncontrollable hypertension (SBP > 160; DBP > 100) or have suffered severe/moderate traumatic brain injury within the last three years eye/chest/abdominal surgery in last 3 months tuberculosis exposure to self or household member history of aneurysm or collapsed lung history of detached retina stroke or heart attack in the last 3 months and history of coughing up blood in last three months (With the exception of hypertension and pregnancy (urine test), all exclusion criteria will be determined via self-report)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 55 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Exposed<br>Veterans deployed to OEF/OIF/OND and environmentally exposed to high levels of particulate matter | |
| Control<br>OEF/OIF/OND Veterans deployed to regions other than Southwest Asia | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| FEV1 | Forced expiratory volume in 1 second (FEV1) measured before and after an exercise challenge | Pre/post exercise; cross-sectional | 
| VO2 Peak | Maximal oxygen consumption measured during exercise | At peak exercise; cross-sectional | 
| Heart Rate Variability | Ratio of low-frequency to high-frequency power for heart rate variability | Resting baseline; cross-sectional | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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exercise tolerance, Veterans, operation enduring freedom, operation Iraqi freedom