Veterans returning from deployment in Southwest Asia who have respiratory symptoms may be difficult to diagnose, according to a study published by Michael J. Morris, MD, of San Antonio Military Medical Center in the American Thoracic Society’s American Journal of Respiratory and Critical Care Medicine.
When in Southwest Asia, military personnel are exposed to an increased level of airborne particulate matter, putting them at risk for acute and chronic lung diseases. “Earlier studies of military personnel deployed in Southwest Asia have shown increases in non-specific respiratory symptoms related to exposure to increased levels of airborne particulate matter,” said Dr. Morris in a news release. “Accordingly, we conducted a prospective study of 50 consecutive individuals returning from active duty in Iraq and/or Afghanistan with new onset pulmonary symptoms to assess possible causes.”
Study participants were evaluated within six months of returning to their duty station. Tests included full pulmonary function testing, high-resolution chest tomography, methacholine challenge testing, and fiberoptic bronchoscopy with bronchoalveolar lavage. If warranted, lung biopsies were also performed. Participants also completed a questionnaire related to deployment history, airborne exposures, smoking history, pulmonary symptoms, and medical treatment.
No specific diagnoses could be made in 42% of patients. Twelve percent of participants tested as normal but had an increased number of neutrophils or lymphocytes that are associated with asthma. Airway hyperreactivity was found in 36% of participants: 16% had asthma and 20% had nonspecific airway hyperreactivity. No participants required a lung biopsy after imaging.
Unrelated to airway symptoms, a significant 66% of participants had underlying mental health and sleep disorders. This seems to agree with the knowledge that military personnel often suffer from post-traumatic stress disorder.
As a result of the study, Dr. Morris recommends, “Evaluation of military personnel returning from duty in Southwest Asia with new onset respiratory symptoms should focus on airway hyperreactivity, although identifying an underlying cause and establishing a diagnosis may be difficult, and additional testing and follow-up may be necessary. Pre-existing underlying disease may play a role in respiratory symptoms in some patients, and mental health and sleep disorders, which were common in our sample, may also play a role in the occurrence of these symptoms.”