Unmet needs for the assessment of small airways dysfunction in asthma: introduction to the ATLANTIS study

An estimated 300 million people suffer from asthma worldwide, which is a major public health problem [1]. Asthma is a chronic inflammatory lung disease that affects the entire bronchial tree. The small airways, i.e. <2 mm diameter, can be affected by inflammation and remodelling, resulting in changes occurring in the smooth muscle cells and the surrounding tissue. These changes all contribute to dysfunction of the small airways, which may contribute to the clinical expression of asthma [2]. However, their contribution to asthma control and exacerbations has been minimally investigated and the majority of studies performed have only occurred in cross-sectional, small-sized patient groups with a narrow spectrum of severity.