Small airway involvement in severe asthma: how common is it and what are its implications?

Asthma is a prevalent chronic respiratory disease affecting all age groups globally, causing significant morbidity and mortality. Small airway involvement, often undetected by traditional spirometry, has emerged as a critical aspect of asthma pathophysiology, especially in severe cases. This retrospective observational study aimed to assess small airway dysfunction using impulse oscillometry (IOS) in 94 severe asthma patients. Results indicated that 27.3% of patients had small airway obstruction. While spirometry showed no statistical differences between groups, IOS parameters were significantly different, highlighting its sensitivity in detecting small airway disease. Patients with small airway involvement exhibited poorer asthma control, emphasizing the clinical relevance of identifying and addressing small airway dysfunction. The study underscores the need for comprehensive evaluation tools like IOS alongside spirometry, especially in severe asthma management. Further large-scale studies are warranted to validate IOS's utility in optimizing therapeutic strategies and improving asthma control, particularly in resource-limited settings. Recognizing and addressing small airway involvement could lead to individualized management approaches and better outcomes in severe asthma patients.