Military personnel exposed to inorganic dust at risk for COPD

Researchers found a 25% increased risk for COPD among U.S. military veterans who took part in duties that had moderate or high likelihoods of exposure to inorganic dust, according to a research letter published in Chest.

Further, this association with dust exposure and COPD risk persisted when researchers evaluated veterans classified as ever smokers, but not for never smokers, according to researchers.

“The observation that COPD risk from military service had a detectable signal underscores that this contribution should be taken seriously,” Paul D. Blanc, MD, MSPH, professor of medicine and endowed chair in the division of occupational and environmental medicine at the University of California, San Francisco, told Healio.

Blanc and colleagues evaluated 427,591 veterans (88.2% men; mean age at entry, 29.9 years ± 7.3; age range, 19-65 years; 63.3% white) who served in Iraq, Afghanistan and surrounding countries starting in 2001 to observe if inorganic dust exposure increased the chances for COPD in this patient population.

In order to calculate the veterans’ exposure to dust during their service, researchers used numeric military occupation codes and a job exposure matrix which grouped their duties according to whether they were likely (high probability), somewhat likely (moderate probability) or not likely (low probability) to have military duties entailing exposure to inorganic dust.

Researchers considered any diagnoses that were reported in Veterans Health Administration records by Sept. 30, 2018, following military discharge.

Of the total cohort, researchers observed that 22.2% of the veterans experienced moderate exposure and 21.6% experienced high exposure to dust in their military service.

According to researchers, 1,728 veterans (0.4%) suffered from COPD, with a median age of diagnosis of 40 years (interquartile range, 32-47 years).

In an unadjusted model, researchers found that combined moderate/high dust exposure was linked to a 25% increased odds of COPD (OR = 1.25; 95% CI, 1.22-1.28).

When evaluating smoking history, researchers found that 67.8% of veterans were classified as ever-smoking whereas 32.2% as never smoking.

Models adjusted for service branch and covariates demonstrated that ever smokers who had a moderate or high probability for inorganic dust exposure had a 23% increased chance for COPD (adjusted OR = 1.23; 95% CI, 1.15-1.31). The risk for COPD was not greater among those who never smoked with the same likelihood of dust exposure (OR = 0.94; 95% CI, 0.87-1.01), according to researchers.

“Clinicians should consider dusty trades in the etiology of COPD, even among smokers, and need to be aware that military service can indeed entail dusty work," Blanc told Healio.

For more information:

Paul D. Blanc, MD, MSPH, can be reached at paul.blanc@ucsf.edu.