Compared with intermittent asthma, persistent asthma is characterized by which of the following?

• A. Nighttime symptoms occur less frequently
• B. Daytime symptoms occur less frequently
• C. Lung function (FEV1) is decreased
• D. Exacerbations requiring oral steroids occur more frequently

Answer: (C)

Persistent asthma involves ongoing airway inflammation with more sustained airway obstruction, which lowers expiratory airflow as measured by FEV1. This reduction in baseline lung function reflects the greater disease burden and partial fixed obstruction that can occur with longer-standing inflammation and remodeling. In intermittent asthma, lung function between episodes is usually normal, so FEV1 remains near normal. While more frequent exacerbations needing oral steroids can occur with persistent disease, the clearest, most characteristic difference is the decreased FEV1.