For which asthma classification is FEV1 expected to be 80% or more?

In the context of asthma classification, the category where FEV1 (Forced Expiratory Volume in 1 second) is expected to be 80% or more is indicative of "Intermittent" asthma. Intermittent asthma is characterized by symptoms that occur fewer than two times a week, and when symptoms do occur, they are brief, typically resolving within a few hours.

The definition of intermittent asthma also includes normal pulmonary function between exacerbations, which correlates with an FEV1 greater than or equal to 80% of the predicted value. This means that patients with this classification do not experience significant airflow obstruction and can achieve nearly normal lung function.

Other classifications such as Mild Persistent, Moderate Persistent, and Severe Persistent asthma involve a range of worsening symptoms, leading to more noticeable reductions in FEV1. Mild Persistent asthma may have an FEV1 greater than or equal to 80% but typically involves more frequent symptoms and require daily medication, contrasting with the intermittent status. Moderate and Severe Persistent asthma present even greater restrictions in lung function and symptom severity, thus having lower FEV1 percentages.