Long-term azithromycin therapy to reduce acute exacerbations in patients with severe chronic obstructive pulmonary disease

Rationale: According to clinical trials, azithromycin taken daily for 1 year, decreased exacerbations of chronic obstructive pulmonary disease (COPD). Objectives: Effectiveness evaluation of long-term azithromycin to reduce exacerbations in severe COPD patient on optimal therapy in real-life practice. Methods: We conducted a retrospective observational study of severe COPD patients who were prescribed azithromycin (PA)(250 mg, at least 3 times weekly for at least 6 months). Comparison group included severe COPD patients not prescribed azithromycin (NPA). Data were extracted from clinical chart review. Main results: Study included 126 PA and 69 NPA patients. They had severe airflow obstruction, mostly emphysema and one-third bronchiectasis. A predominant feature in the PA group was respiratory tract colonization with Pseudomonas aeruginosa. The mean number of exacerbations per patient per year in the PA group was 3.2 +/- 2.1 before initiating azithromycin, and 2.3 +/- 1.6 during following year on therapy (p < 0.001). Patients in the NPA group had 1.7 +/- 1.3 and 2.5 +/- 1.7 exacerbations during first and second follow-up year respectively (p < 0.001). Exacerbation changes from pre to post differed between groups (p < 0.001). Decrease in emergency visits and hospital admissions was significant in PA group. Exacerbation reductions and patient proportions having >= 2 exacerbations extended to the second year of treatment. Conclusion: These data showed that long-term azithromycin reduces exacerbation numbers in severe COPD patients, and benefits persist beyond one year. Desirable effects are more likely to outweigh the risks and adverse events in patients colonized with Pseudomonas aeruginosa.