Small Airways Disease and Asthma Management: Is there a Connection?

We reviewed literature on the assessment and prevalence of small airways impairment in asthma and the relationships between small airways disease (SAD) and asthma clinical characteristics. The effects of treatments targeting small airways alterations are also discussed. We performed a PubMed search, using “asthma AND small airways” and “small airways AND treatment”. All identified works were reviewed for adequacy, including reviews, randomised clinical trials and real-life studies. We found evidence that SAD is highly prevalent in the asthma population, throughout all degrees of severity. SAD seems particularly pronounced in some specific phenotypes and in severe asthma. Further studies are needed to investigate the mechanisms of the association between SAD and clinical outcomes such as symptom control and exacerbation risk. The inhaled treatment with recently developed small particle size formulations warrants a greater drug deposition in the more peripheral district and positively affects clinical outcomes while reducing the overall drug exposure.