Airway closure on imaging relates to airway hyperresponsiveness and peripheral airway disease in asthma

摘要

asthma is characterized by intermittent airway narrowing and airway closure, which cause typical symptoms of wheeze, breathlessness, and chest tightness. Airway closure occurs during bronchial challenge [measured by a decrease in forced vital capacity (FVC) (5, 9, 34) and an increase in closing capacity (CC) (43)] and is associated with more severe asthma in terms of greater risk of exacerbations (9, 14, 34). Airway hyperresponsiveness (AHR) in asthma is also associated with more severe and poorly controlled disease, greater risk of hospitalization (32), and lung function decline (35). AHR is characterized by loss of the maximal response plateau, which implies that asthmatic airways may narrow to complete closure (26). Despite important associations between excessive airway closure and poor clinical outcomes, the mechanisms behind closure are poorly understood, and the relationship between airway closure and AHR is unclear.