Reducing Exacerbations in the Inner City: Lessons from the Inner-City Asthma Consortium (ICAC)

Asthma exacerbations are important components of asthma morbidity. The Inner-City Asthma Consortium was established in the early 1990s to identify risk factors for and to evaluate treatments to reduce asthma symptoms and exacerbations. Early studies identified atopy and inadequate treatment as important drivers of asthma morbidity. Later studies demonstrated that good adherence to guidelines-based asthma care could virtually eliminate symptoms and reduce but not eliminate exacerbations. Looking at exacerbations by season, risk factors were found to vary across the different seasons. Of the 7 factors identified, allergic status and pulmonary functions were found to be important for exacerbations in all seasons, but allergy had its strongest effect in the fall season. Therefore, additional therapy directed at reducing the role of allergy was evaluated and found to significantly reduce exacerbations even in participants with good symptom control when receiving guidelines-based therapy. Despite this year around aggressive therapy, exacerbations remain albeit at a lower level and with less seasonal variation. Another strategy, the short term use of therapy aimed at reducing the role of allergy begun before the fall season and focused on individuals at high risk for exacerbations, was found to be an effective approach to minimize exacerbations and to limit the amount of therapy necessary.