Holly Keir, PhD: Changes in Microbiome Observed Following ICS Withdrawal in Patients with COPD

A new investigation into inhaled corticosteroids (ICS) found that patients with moderate to very severe chronic obstructive pulmonary disorder (COPD) who withdrew from treatment experienced favorable changes in microbiome composition and improvements in exacerbations.

The new data were presented today at the American Thoracic Society 2022 International Conference in San Francisco.

Though ICS have been shown to reduce exacerbation frequency in patients with COPD and eosinophilic inflammation, they have also been linked to an increased risk of pneumonia.

Additionally, previous research cited an increase in bacterial load in patients who with eosinophilic disease who were treated with ICS.

With the present study, an investigative team led by Holly Keir, PhD, of the University of Dundee, hypothesized that ICS withdrawal would reduce bacterial load and modify the airway microbiome in a study of 80 patients with COPD.

Patients were randomized to receive either Tiotropium and Olodaterol (ICS withdrawal) or Fluticasone Furoate/Vilanterol (ICS continuation) for 6 months.

“Interestingly, we didn't see that reduction in bacterial load that we're expecting to see when we withdrew ICS; however, we did see changes to the microbiome itself,” Keir said. “So, we saw massive changes in beta diversity following ICS withdrawals. When we looked in more detail about what was driving those changes, we found that in patients who had ICS withdrawal had an increase in commensal taxa, which we typically see as beneficial.”

In patients who continued ICS, Keir and colleagues observed higher levels of things like haemophilus and streptococcus, which are known to be pathogenic in those with COPD.

Lugogo added that the results of the study were in line with the ERS international guideline recommendations, which suggest that patients with an eosinophil count of less than 300 cells per microliter, less than two exacerbations, and 2 exacerbations per year, should consider withdrawing ICS.

“That's what we want people to think about- thinking about the ERS guidelines, looking at the blood eosinophil count and thinking if they're on ICS, do we actually need to withdraw? Can we reduce exacerbations? And when can we get patients that more favorable microbiome?”

Watch the full interview with Dr. Keir above, and click here for more news from ATS 2022.