Population health for children with asthma: time to let some fresh air in.

I must confess that as a primary care pediatrician, treating asthma often feels stale: same old medications, same old conversations about the importance of daily controllers, same old preventable emergency department visits and hospitalizations. But in this issue of Pediatrics, Beck et al present a novel ecologic analysis that sheds new light on the topic, linking the asthma medication ratio (AMR; the ratio of asthma controller prescriptions filled to all asthma prescriptions filled) measured at the level of individual community pharmacies with pediatric asthma exacerbations within the census tract in which the pharmacy is located. The magnitude of the association was substantial, with a decrease of nearly 10 asthma exacerbations per 1000 children per year for each 0.1 increase in the pharmacy-level AMR. This central finding suggests that a low communitylevel AMR highlights a “hot spot” in which untoward asthma events are likely to occur at an increased rate relative to other areas with better community AMRs, even after adjustment for known confounders. Although ecologic analyses such as this one always raise the specter of unappreciated confounding (which may lead to overestimating the correlation), it is likely that the authors are onto something, given the wealth of studies supporting the association between individual patient-level AMR and asthma exacerbations.