By Brenda L. Mooney
SAN DIEGO ─ Veterans returning from Iraq/Afghanistan and the Gulf War with pulmonary function abnormalities have a significantly greater risk of developing chronic respiratory disease years later, according to a new study presented at the 2014 American Thoracic Society International Conference in San Diego.1
“Previous studies of Gulf War and Iraq/Afghanistan veterans have found persistent respiratory symptoms decades after their deployment but have not always detected clinically significant pulmonary abnormalities,” said lead author Michael Falvo, PhD, a research physiologist at the VA’s War Related Illness and Injury Study Center. “In our study, however, we found evidence of small airway obstruction and other pulmonary abnormalities in many deployed veterans.”
Asthma, chronic obstructive pulmonary disease and other respiratory issues can stem from small airway obstruction.
The study was a departure from previous research in both U.S. and Australian 1991 Gulf War veterans which observed no clinically significant pulmonary abnormalities in deployed veterans despite the presence of symptoms that persist even 20 years later.
Increased respiratory symptom reporting up to 10 years post-deployment also has been an issue among Iraq and Afghanistan veterans (IAV), leading researchers to compare patterns of pulmonary function abnormalities in Gulf War and IAV veterans evaluated at a post-deployment tertiary-care clinic in comparison to a previously published population-based sample of Gulf War veterans evaluated 10 years post-deployment.
The earlier study found identical pulmonary function test results among deployed and nondeployed Gulf War veterans.2
“Our findings did not confirm the hypothesis that deployment to the Gulf War in 1990-91 resulted in increased prevalence of clinically significant pulmonary abnormalities 10 years later, wrote the authors led by Joel B. Karlinsky, MD, of the Boston VAMC and Boston University.
For the recently presented retrospective study, researchers tracked 63 Gulf War veterans approximately 20 years post-deployment and 70 Iraq/Afghanistan veterans about 10 years post-deployment. Study subjects were classified as follows: 1) Normal Pulmonary Function (NPF); 2) Non-Reversible Airway Obstruction (NRAO); 3) Reversible Airway Obstruction (RAO); 4) Restrictive Lung Physiology (RLP); and 5) Small Airway Obstruction (SAO). Categories and prediction equations from the Karlinsky study were used for consistency.
With pulmonary function abnormalities assessed using spirometry, the newer study found that small airway obstruction was five times greater — 38% vs. 7% — and the rate of restrictive lung physiology was twice as much — 24% vs. 12% — among Gulf War veterans compared with a reference group from an earlier population-based sample of Gulf War veterans evaluated 10 years post-deployment. In the Iraq/Afghanistan veterans, meanwhile, the rate of small airway obstruction was also five times greater, 31% vs. 7%, but rates of nonreversible airway obstruction were significantly lower in the study groups than in the reference sample.