Journal club in Thorax this month (Thorax 2012;67:391 doi:10.1136/thoraxjnl-2011-201189) refers to the NEJM paper from last year showing a prolongation of time to first exacerbation in COPD when patients were treated with Azithromycin (NEJM 2011;365:689).  They cautioned the use of macrolides in those at risk of prolonged QTc, and tachycardia, along with the note of hearing loss risk.

What the study didn't do effectively enough to my mind, is phenotype the COPD patients.  COPD is not a homogenous disease, with some patients having almost exclusively emphysema, and others having,essentially, smoking related bronchiectasis.  It be a wouldn't  massive surprise to discover that azithromycin improves outcome in those patients with a bronchiectatic phenotype, but the studies so far have not separated out those with a predominant emphysema component, from those with bronchiectasis.

The debate continues...