Small airways dysfunction in severe asthma: Current treatment approaches and future directions.

Severe asthma is a significant health concern due to its association with higher mortality rates, reduced quality of life, and increased healthcare costs. These challenges make it a persistent issue for both clinicians and researchers. The small airways, defined as distal airways with a diameter of less than 2 mm and comprising 98.8% of the total lung volume, play a significant role in airway resistance in individuals with asthma. Recent studies demonstrated that small airways dysfunction is found in all asthma severity levels, but it is most pronounced in severe asthma, and greater small airways dysfunction severity correlates with poorer asthma control and a higher frequency of exacerbations. Therefore, therapies aimed at targeting small airways dysfunction are essential for effective asthma management, especially in severe asthma.