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Published on: January 22, 2021
Effect of long term treatment with azithromycin on disease parameters in cystic fibrosis: a randomised trial
1University Department of Medicine and Department of Infectious Disease, Mater Adult Hospital, Brisbane, Australia.
Background:
Relentless chronic pulmonary inflammation is the major contributor to morbidity and mortality in patients with cystic fibrosis (CF). While immunomodulating therapies such as prednisolone and ibuprofen may be beneficial, their use is limited by side effects. Macrolides have immunomodulatory properties and long term use dramatically improves prognosis in diffuse panbronchiolitis, a condition with features in common with the lung disease of CF.
Methods:
To determine if azithromycin (AZM) improves clinical parameters and reduces inflammation in patients with CF, a 3 month prospective randomised double blind, placebo controlled study of AZM (250 mg/day) was undertaken in adults with CF. Monthly assessment included lung function, weight, and quality of life (QOL). Blood and sputum collection assessed systemic inflammation and changes in bacterial flora. Respiratory exacerbations were treated according to the policy of the CF Unit.
Results:
Sixty patients were recruited (29 men) of mean (SD) age 27.9 (6.5) years and initial forced expiratory volume in 1 second (FEV1) 56.6 (22.3)% predicted. FEV1% and forced vital capacity (FVC)% predicted were maintained in the AZM group while in the placebo group there was a mean (SE) decline of -3.62 (1.78)% (p=0.047) and -5.73 (1.66)% (p=0.001), respectively. Fewer courses of intravenous antibiotics were used in patients on AZM (0.37 v 1.13, p=0.016). Median C reactive protein (CRP) levels declined in the AZM group from 10 to 5.4 mg/ml but remained constant in the placebo group (p<0.001). QOL improved over time in patients on AZM and remained unchanged in those on placebo (p=0.035).
Conclusion:
AZM in adults with CF significantly improved QOL, reduced CRP levels and the number of respiratory exacerbations, and reduced the rate of decline in lung function. Long term AZM may have a significant impact on morbidity and mortality in patients with CF. Further studies are required to define frequency of dosing and duration of benefit.
Insights
Azithromycin (AZM) improved quality of life and lung function in cystic fibrosis (CF) patients. This macrolide antibiotic reduced inflammation and respiratory exacerbations, offering potential long-term benefits for CF morbidity and mortality.
Area of Science:
- Pulmonology
- Clinical Pharmacology
Background:
- Chronic pulmonary inflammation significantly contributes to morbidity and mortality in cystic fibrosis (CF).
- Existing immunomodulating therapies for CF have limitations due to side effects.
- Macrolides demonstrate immunomodulatory properties and improve outcomes in related lung conditions like diffuse panbronchiolitis.
Purpose of the Study:
- To evaluate the efficacy of azithromycin (AZM) in improving clinical parameters and reducing inflammation in adult patients with CF.
- To assess the impact of AZM on lung function, weight, quality of life, and inflammatory markers over a 3-month period.
Main Methods:
- A prospective, randomized, double-blind, placebo-controlled study involving adult CF patients.
- Participants received either AZM (250 mg/day) or a placebo for 3 months.
- Monthly assessments included lung function tests, weight, quality of life questionnaires, and analysis of blood and sputum for inflammatory markers and bacterial flora.
Main Results:
- Azithromycin (AZM) maintained forced expiratory volume in 1 second (FEV1)% and forced vital capacity (FVC)% predicted, while the placebo group showed a significant decline.
- Patients receiving AZM required fewer courses of intravenous antibiotics compared to the placebo group (0.37 vs. 1.13).
- Median C-reactive protein (CRP) levels decreased significantly in the AZM group, and quality of life scores improved compared to the placebo group.
Conclusions:
- Azithromycin (AZM) significantly improved quality of life, reduced CRP levels, and decreased the number of respiratory exacerbations in adult CF patients.
- AZM treatment helped maintain lung function, suggesting a reduced rate of decline.
- Long-term azithromycin therapy holds promise for impacting morbidity and mortality in cystic fibrosis, warranting further investigation into optimal dosing and duration.
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