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Azithromycin of questionable benefit given daily for COPD

Clinical Question:
Does daily use of azithromycin 250 mg improve outcomes for patients with chronic obstructive pulmonary disease?

Bottom Line:
In a carefully selected group of high-risk patients with chronic obstructive pulmonary disease (COPD), chronic use of azithromycin reduces exacerbations (number needed to treat [NNT] = 3) and slightly reduces hospitalizations for COPD (NNT = 13), but does not change the total number of hospitalizations. The cost is approximately $1200 per year (www.drugstore.com, 9/7/11) for this benefit, so it is of questionable cost-effectiveness, and hearing loss is a concern. (LOE = 1b)

Albert RK, Connett J, Bailey WC, et al. Azithromycin for prevention of exacerbations of COPD. N Engl J Med 2011;365(8):689-698.  [PMID:21864166]

Study Design:
Randomized controlled trial (double-blinded)


Outpatient (any)

Azithromycin has antibacterial and antiinflammatory properties, so perhaps it is useful for patients with COPD. This study included patients with COPD who were older than 40 years, had at least 10 pack-years of smoking, an FEV1 to FVC ratio of less than 70%, and postbronchodilator FEV1 of less than 80% predicted. All patients also had to have been using supplemental oxygen, using corticosteroids, or had an exacerbation requiring hospitalization or an emergency department visit within the past year. Patients with prolonged QT interval, hearing impairment, or resting tachycardia were excluded. The 1142 patients were randomized to receive either azithromycin 250 mg once daily or matching placebo, and were followed up for 1 year. Groups were balanced, the patients' mean age was 65 years, and 60% were using supplemental oxygen. Follow-up was good, with approximately 90% completing the study. Analysis was by intention to treat. There were 0.36 fewer exacerbations per year in treated patients, for an NNT to prevent 1 exacerbation of just under 3. However, most of these exacerbations did not require hospitalization. The NNT to prevent 1 hospitalization for COPD was approximately 13, and there was actually no difference between groups in the total number of hospitalizations for any cause. There was also no difference in mortality (3% vs 4%). Hearing loss was relatively common, occurring in 142 in the intervention group and 110 in the placebo group (number needed to treat to harm = 20); it returned to baseline after at least a month of the drug in only one-third of patients. The clinical significance of this hearing loss is not completely clear.


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