Worsening dyspnea after asthma treatment common among World Trade Center responders

In a cohort of firefighters who responded to the World Trade Center within 2 weeks of 9/11, worsening dyspnea was common after treatment with inhaled corticosteroids combined with long-acting beta agonists, according to a study published in Annals of the American Thoracic Society.

From a cohort of 9,638 male firefighters who first arrived at the World Trade Center site between Sept. 11 and 24, 2001, Michael Weiden, MS, MD, professor of medicine and environmental medicine in the division of pulmonary and critical care medicine at New York University School of Medicine, and colleagues evaluated 1,073 patients who received inhaled corticosteroids in combination with LABA therapy for more than 2 years. All patients had at least one modified Medical Research Council (mMRC) dyspnea score before treatment and two mMRC scores after. Patients completed monitoring questionnaires including mMRC scores between Aug. 1, 2005, and Sept. 10, 2018.

Fifty-three percent of patients responded to treatment, meaning they had an mMRC less than 0 after treatment initiation, and 47% did not, according to the data. Results showed that non-responders had increased mMRC scores 11 years after World Trade Center exposure, with worse dyspnea scores at the end of follow-up (1.55 vs. 0.79). In an analysis of dyspnea trajectory in relation to treatment, the researchers found that responders also had a steep increase in mMRC scores before treatment, whereas non-responders had a gradual increase in mMRC scores before treatment that continued after treatment initiation.

According to the researchers, increased time between World Trade Center exposure and treatment initiation strongly predicted non-response to therapy, but higher mMRC before treatment was linked to a favorable treatment response. Non-responders also had a longer time between World Trade Center exposure and symptom onset.

“Almost half of patients who are treated for World Trade Center lung injury have worse shortness of breath after asthma treatment is started,” Weiden told Healio Pulmonology. “Patients who present long after irritant exposure have a different type of lung injury. Their symptoms respond less well to inhaled steroids and LABAs. More research of the type of asthma (endotype) that has delayed onset is needed moving forward.” – by Erin T. Welsh

Disclosures: The authors report no relevant financial disclosures.