Lifetime Prevalence of Respiratory Diseases and Exposures Among Veterans of Operation Enduring Freedom and Operation Iraqi Freedom Veterans: Results From the National Health Study for a New Generation of U.S. Veterans

Impact of poor air quality while deployed on respiratory health: a systematic review

INTRODUCTION

British military personnel deploy internationally to areas with high levels of ambient air pollution. Air pollution can cause acute respiratory symptoms which lead to concern about potential long-lasting health effects. There is a requirement for evidence-based policy on chronic respiratory disease associated with military deployments to areas with poor air quality (AQ). This literature review examines the published evidence relating to the development of chronic respiratory disease in military personnel after exposure to poor AQ while deployed.

METHODS

A literature search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Embase, MEDLINE and Global health databases were searched for English language studies published since 2014 examining the respiratory health of military personnel deployed to Southwest Asia since 2001. A quality appraisal of selected articles was conducted using the Critical Appraisals Skills Programme checklist and a descriptive review completed.

RESULTS

Eleven studies were found, eight of which had objective outcome measures. Two prospective cohort studies were included; the remainder of the data were retrospective.

CONCLUSION

High rates of respiratory symptoms are reported by personnel who deploy to areas of poor AQ, giving rise to high levels of concern. Spirometry testing has found mild deficits, mostly of an obstructive nature, in a third of those with ongoing symptoms post deployment. These have not been consistently linked with deployment length. An increased risk of asthma appears to be multi-factorial in aetiology and there is no evidence for an increased risk of chronic obstructive pulmonary disease or histological pathology post deployment. At present, there is no definitive evidence of chronic respiratory disease due to exposure to poor AQ while deployed. Further objective longitudinal studies are required to continue to investigate the association, diagnosis and management of those with ongoing symptoms.

Deployment-Related Respiratory Disease: Where Are We?

Military personnel and veterans who have deployed to Afghanistan, Iraq, and parts of Southwest Asia (SWA) since 1990 are at risk of developing a host of respiratory symptoms and deployment-related respiratory diseases (DRRDs). This review aims to summarize our current understanding of DRRD and inform pulmonary practitioners of recent updates to DRRD screening, diagnosis, evaluation, and management. The most common respiratory diseases in these patients include asthma, chronic sinonasal disease, laryngeal disease/dysfunction, and distal lung disease. Pulmonary function testing and chest imaging are the most commonly used diagnostic tools, but techniques such as lung clearance index testing via multiple breath washout, forced oscillation testing/impulse oscillometry, and quantitative chest computed tomography (CT) assessment appear promising as noninvasive modalities to aid in lung disease detection in this population. We also summarize guidance on conducting an occupational and deployment exposure history as well as recommendations for testing. Finally, we discuss the Sergeant First Class Heath Robinson Honoring our Promise to Address Comprehensive Toxics Act of 2022 (PACT Act) that includes a list of health conditions that are "presumptively" considered to be related to SWA military deployment toxic exposures, and provide resources for clinicians who evaluate and treat patients with DRRD.

Physical health of Post-9/11 U.S. Military veterans in the context of Healthy People 2020 targeted topic areas: Results from the Comparative Health Assessment Interview Research Study

Large-scale epidemiological studies suggest that veterans may have poorer physical health than nonveterans, but this has been largely unexamined in post-9/11 veterans despite research indicating their high levels of disability and healthcare utilization. Additionally, little investigation has been conducted on sex-based differences and interactions by veteran status. Notably, few studies have explored veteran physical health in relation to national health guidelines. Self-reported, weighted data were analyzed on post-9/11 U.S. veterans and nonveterans (n = 19,693; 6,992 women, 12,701 men; 15,160 veterans, 4,533 nonveterans). Prevalence was estimated for 24 physical health conditions classified by Healthy People 2020 targeted topic areas. Associations between physical health outcomes and veteran status were evaluated using bivariable and multivariable analyses. Back/neck pain was most reported by veterans (49.3 %), twice that of nonveterans (22.8 %)(p < 0.001). Adjusted odds ratios (AORs) for musculoskeletal and hearing disorders, traumatic brain injury, and chronic fatigue syndrome (CFS) were 3-6 times higher in veterans versus nonveterans (p < 0.001). Women versus men had the greatest adjusted odds for bladder infections (males:females, AOR = 0.08, 95 % CI:0.04-0.18)(p < 0.001), and greater odds than men for multiple sclerosis, CFS, cancer, irritable bowel syndrome/colitis, respiratory disease, some musculoskeletal disorders, and vision loss (p < 0.05). Cardiovascular-related conditions were most prominent for men (p < 0.001). Veteran status by sex interactions were found for obesity (p < 0.03; greater for male veterans) and migraine (p < 0.01; greater for females). Healthy People 2020 targeted topic areas exclude some important physical health conditions that are associated with being a veteran. National health guidelines for Americans should provide greater consideration of veterans in their design.

Military deployment-related respiratory problems: an update

PURPOSE OF REVIEW

Military personnel deployed to Southwest Asia and Afghanistan were potentially exposed to high levels of fine particulate matter and other pollutants from multiple sources, including dust storms, burn pit emissions from open-air waste burning, local ambient air pollution, and a range of military service-related activities that can generate airborne exposures. These exposures, individually or in combination, can have adverse respiratory health effects. We review exposures and potential health impacts, providing a framework for evaluation.

RECENT FINDINGS

Particulate matter exposures during deployment exceeded U.S. National Ambient Air Quality Standards. Epidemiologic studies and case series suggest that in postdeployment Veterans with respiratory symptoms, asthma is the most commonly diagnosed illness. Small airway abnormalities, most notably particularly constrictive bronchiolitis, have been reported in a small number of deployers, but many are left without an established diagnosis for their respiratory symptoms. The Promise to Address Comprehensive Toxics Act was enacted to provide care for conditions presumed to be related to deployment exposures. Rigorous study of long-term postdeployment health has been limited.

SUMMARY

Veterans postdeployment to Southwest Asia and Afghanistan with respiratory symptoms should undergo an exposure assessment and comprehensive medical evaluation. If required, more advanced diagnostic considerations should be utilized in a setting that can provide multidisciplinary expertise and long-term follow-up.

The Impact of Deployment and Combat Exposure on Physical Health Among Military Personnel: A Systematic Review of Incidence, Prevalence, and Risks

OBJECTIVES

The impact of deployment and combat on mental health of military personnel is well described. Less evidence is available to demonstrate and summarize the incidence, prevalence, and risks of these exposures on physical health. This study aims to (1) systematically review the available literature to determine the incidence and prevalence of physical health conditions among military personnel during and after deployment and (2) investigate the risks of deployment and combat exposure on physical health.

METHODS

A systematic review using the PubMed and EMBASE databases was performed. The literature search was limited to articles written in English, published from 2000 through 2019. The quality of studies was assessed with the Joanna Briggs Institute Appraisal Checklist. The results were grouped per system or condition of physical health and presented by forest plots without a combined effect size estimate.

RESULTS

Thirty-two studies were found eligible for this review. We identified a wide variety of incidence and prevalence rates of numerous physical health conditions and a high heterogeneity across the included studies. Acute respiratory symptoms, diarrhea, musculoskeletal injuries, pain, and tinnitus were found to be the most incident or prevalent conditions. Except for hearing loss, no associations with deployment and physical health problems were observed. An increased risk for asthma, headache, hearing loss, and pain was reported in relation to the combat exposure.

CONCLUSION

Given the characteristics of included studies and extracted data, the magnitude of the found differences in incidence and prevalence rates is most likely to be due to methodological heterogeneity. The specific exposures (e.g., infrastructure, environmental conditions, and activities during deployment) are suggested to be the determinants of (post) deployment physical health problems and need to be addressed to decrease the impact of deployment. Findings from this systematic review highlight which conditions should be addressed in response to service members' health and wellness needs in the (post)deployment phase and may be used by clinicians, researchers, and policy-makers. However, knowledge gaps regarding the potential risk factors during deployment and combat still exist. Studies using consistent methods to define and measure the physical health conditions and specific exposures are needed.

Cytotoxic Effects of N,N-Diethyl-Meta-Toluamide (DEET) on Sinonasal Epithelia

Although the etiology of chronic rhinosinusitis remains unknown, environmental factors including airborne pollutants and toxicants are postulated to contribute to its pathogenesis. However, the precise pathomechanisms with which environmental toxicants may contribute to chronic rhinosinusitis are not fully understood. The purpose of this pilot study is to examine the cytotoxic effects of N,N-diethyl-meta-toluamide (DEET), a commonly used pesticide, on sinonasal epithelial cells (SNECs). Sinus mucosa was obtained from 3 subjects without a history of chronic rhinosinusitis. Cultured SNECs were exposed to various concentrations of DEET (0-5 mM) for 6 days. Cell viability, proliferation, and morphologic changes were assessed using the MTT colorimetric dye assay and the Incucyte Live Cell Monitoring System. Statistically significant dose-dependent reduction in cell viability and proliferation was observed between exposure and control groups (P < .05) at all concentrations tested. Dose-dependent cellular morphological changes were also seen. These findings indicate that DEET exposure induces dose-dependent cytotoxicity in sinonasal epithelia.

Combat zone exposure and respiratory tract disease

BACKGROUND

The impact of deployment to combat zones on the respiratory and sinonasal health of U.S. soldiers is an emerging public health concern. Retrospective studies have shown a correlation between deployment and development of post-deployment pathology, particularly of the aerodigestive system. Respiratory disease, including sinusitis, allergic rhinitis, and asthma, are commonly reported in soldiers deployed to the Middle East and Southwest Asia.

METHODS

Current literature pertaining to combat zone exposure and development of respiratory disease was retrieved using PubMed, Embase, Web of Science, and Google Scholar.

RESULTS

Several types of combat zone exposures exist that may play an influential role in the development of upper and lower respiratory tract diseases. Exposures including foreign dusts, harsh environments, particulate size, and close living quarters may play a causative role. The effect of combat zone exposures has been better examined for lower respiratory tract diseases; however, with the theory of the unified airway, the upper respiratory tract may also be involved. There is evidence that the upper respiratory tract is susceptible, with an increased risk for development of sinusitis and sinonasal disease; however, the quality of evidence of the present literature is generally low.

CONCLUSION

More research is necessary to determine a pathophysiologic mechanism between combat zone exposure and the development of sinonasal disease. Practicing otolaryngologists should be aware of the possibility of combat zone exposures that could contribute to rhinologic symptomatology.