Am J Respir Crit Care Med. 2021 Aug 31. doi: 10.1164/rccm.202102-0289OC. Online ahead of print.
RATIONALE: Inhaled corticosteroids (ICS) are commonly prescribed with long-acting beta-2 agonists (LABA) in COPD. To date, the effects of ICS therapy on the airway microbiome in COPD are unknown.
OBJECTIVES: To determine the effects of ICS/LABA on the airway microbiome of COPD patients.
METHODS: Clinically stable COPD patients were enrolled into a 4-week run-in period during which ICS was discontinued and all participants were placed on formoterol 12 µg twice daily (BID). The participants were then randomized to: budesonide/formoterol (Bud + Form; 400/12 µg BID), fluticasone/salmeterol (Flu + Salm; 250/50 µg BID) or formoterol only (Form; 12 µg BID) for 12 weeks. Participants underwent bronchoscopy before and after the 12-week treatment period. The primary endpoint was the comparison of changes in the airway microbiome over the trial period between the ICS/LABA and LABA-only groups.
MEASUREMENTS AND MAIN RESULTS: 63 participants underwent randomization: Bud + Form (n=20), Flu + Salm (n=22) and Form (n=21) groups; 56 subjects completed all visits. After the treatment period, changes in alpha diversity were significantly different across groups, especially between Flu + Salm and Form groups (Δ richness: p = 0.02; Δ Shannon Index: p = 0.03). Longitudinal differential abundance analyses revealed more pronounced microbial shifts from baseline in the fluticasone (vs. budesonide or formoterol only) group.
CONCLUSIONS: Fluticasone-based ICS/LABA therapy modifies the airway microbiome in COPD, leading to a relative reduction in alpha diversity and a greater number of bacterial taxa changes. These data may have implications in patients who develop pneumonia on ICS. Clinical trial registration available at www.clinicaltrials.gov, ID:NCT02833480.
PMID:34464242 | DOI:10.1164/rccm.202102-0289OC