Antibiotic changes in pulmonary exacerbation treatment not beneficial in cystic fibrosis

Key takeaways:

• A larger lung function improvement was not seen with vs. without antibiotic changes in pulmonary exacerbation treatment.
• Future pulmonary exacerbations were not less likely to occur following antibiotic changes.

In patients aged 6 to 21 years with cystic fibrosis receiving pulmonary exacerbation treatment, changing antibiotics was not clinically beneficial, according to results published in Annals of the American Thoracic Society.

“Our findings illustrate that changing IV antibiotics during pulmonary exacerbation treatment among children and adolescents with CF is not associated with clinical improvements, including a larger improvement in pre- to post-pulmonary exacerbation lung function,” Jonathan D. Cogen, MD, MPH, attending physician in the division of pulmonary and sleep medicine at Seattle Children’s Hospital, told Healio.

“These results provide an opportunity for CF clinicians to limit the overall antibiotic burden that people with CF receive when admitted for pulmonary exacerbation management,” Cogen continued.

In a retrospective cohort study, Cogen and colleagues assessed 4,099 patients with CF treated with intravenous antibiotics for pulmonary exacerbations to determine how changing antibiotics impacts clinical outcomes.

When any intravenous antibiotic was added or subtracted between a patient’s sixth day in the hospital and the day before discharge, researchers classified this as an antibiotic change.

Patient data were obtained from the Cystic Fibrosis Foundation Patient Registry Pediatric Health Information System linked dataset, and researchers adjusted for disease severity and indication bias in this analysis.

The total number of pulmonary exacerbations in this cohort was 18,745. Among those who experienced a change in intravenous antibiotics, researchers found a total of 8,169 pulmonary exacerbations.

When comparing lung function rates from before treatment with after treatment, researchers found a lower mean change in percent-predicted FEV₁ among patients who had an antibiotic change than in patients who did not have an antibiotic change (11.3 vs. 12.2; P = .001).

Between the two sets of patients, a change in antibiotics during treatment was linked to a lower likelihood of returning to 90% or higher of baseline percent-predicted FEV₁ (OR = 0.89; 95% CI, 0.8-0.98).

When evaluating odds for future pulmonary exacerbations, researchers found further evidence demonstrating that antibiotic changes are not related to clinical improvement, as these changes raised the likelihood for this outcome (OR = 1.17; 95% CI, 1.12-1.22).

In contrast, there was no significant difference in the likelihood of returning to 100% or higher of baseline percent-predicted FEV₁ when comparing the two patient groups.

Notably, all the above outcomes did not significantly differ between those with antibiotic changes and those without antibiotic changes during treatment in an analysis that only considered one pulmonary exacerbation per person.

“Antimicrobial stewardship principles — including optimizing antibiotic selection — remain important in the care of people with CF,” Cogen told Healio.

When asked about future research, Cogen said a randomized controlled trial evaluating antibiotic changes could be beneficial.

“This future study would need to first determine which people with CF are not improving enough to then be randomized to continuing their current admission therapy or trying something different,” Cogen said.

“Realistically, this particular study question might not be prioritized for a randomized controlled trial, but certainly this study question can be explored in other large datasets, and if similar results were found in another CF population or in a different dataset, that would only strengthen our findings,” he said.