Studies about Macrolides and COPD Treatment
Several small studies have tested whether macrolide antibiotic use can decrease the frequency of acute exacerbations. At least two of those studies showed no effect, but other results have been more promising. For example, a recent study in the journal Respiration found that six months of treatment with the macrolide antibiotic erythromycin reduced exacerbations in 16 people with COPD who had recently experienced a flare. The investigators also found that neutrophil counts in the sputum (a measure of inflammation) were lower in erythromycin users than in a similar group that wasn't treated.
To shed more light on the subject, researchers from the COPD Clinical Research Network (CCRN) conducted a much larger and longer study to determine whether azithromycin could reduce the frequency of exacerbations in people at high risk for flares. High risk meant that in addition to having moderate to severe COPD, study participants must also have been using supplemental oxygen or needed oxygen or systemic steroids in the previous year or had a flare that required emergency treatment or a hospital stay in that time.
The researchers identified 1,142 people who met those criteria and randomly assigned them to take 250 mg of azithromycin or a placebo for 12 months. All participants continued using the same COPD medications they had been taking. At one year, the azithromycin group had significantly fewer exacerbations.
The likelihood of experiencing an exacerbation decreased by 27 percent in the azithromycin group. In addition, the time to first exacerbation was nearly nine months for the azithromycin group compared with about six months for the placebo group.
The researchers also looked at the effect of long-term antibiotic use on the participants' quality of life (QOL) by examining various factors, including their sense of their health, the effect of dyspnea, or breathlessness, on their activities and the effect of COPD on their ability to function socially and psychologically.
While the overall change from the beginning of the study to the end was not significant for either group, there were significant differences between the two groups. The average improvement in QOL score was four times greater in the azithromycin group. And a greater percentage of people in the azithromycin group (43 percent vs. 36 percent) achieved a change in score that was important enough to make a real difference in the quality of their lives.
The Bottom Line
The results from the study of azithromycin in people with COPD strongly suggest that it can benefit those at high risk for exacerbations. Does that mean you should take it if you're at high risk? Not necessarily.
Certainly, the therapy is not appropriate if you're at risk for arrhythmias or have more than a minimal degree of hearing loss. If neither of these issues is a concern, review your current treatment plan with your doctor. If it measures up to current guidelines, and you're following it as prescribed, you and your doctor should weigh the benefits and risks of therapy as they pertain to your particular situation.
Keep in mind that antibiotic therapy is not a replacement for the medications you're already taking for COPD; you'll need to continue using them. Also you'll need to have your hearing checked regularly, and your doctor will need to monitor the antibiotic resistance patterns in your community.
In addition, treatment has not been studied beyond one year, so the risks and benefits of extending antibiotic therapy beyond that time are unknown.