Hard-to-control asthma has distinct features, study shows

Bronchodilator responsiveness, nasal inflammation and allergy were among the most significant baseline features that distinguished hard-to-control asthma in inner-city children and adolescents. These characteristics identified patients whose asthma did not improve throughout the year, despite adherence to the most intensive treatment based on national guidelines. Patients with hard-to-control asthma also had exacerbations peaking in the spring and fall, and more nighttime symptoms in the fall and winter.