Asthma is an inflammatory condition of both the small and large airways.
Small airways have gained increasing attention as studies have shown significant inflammation in the small airways in all severities of asthma. Noninvasive methods to reliably measure small airways are being actively explored.
Recent changes in asthma inhalers have led to alterations in drug formulations and development of extrafine particles that may improve delivery to the distal airways.
Role of Small Airways in Asthma. Finkas LK, Martin R. Immunol Allergy Clin North Am. 2016 Aug;36(3):473-82. doi: 10.1016/j.iac.2016.03.009.
The World Allergy Organization (WAO) Small Airways Working Group publishes a monthly "What's New?" summary and I have served as its editor since 2011. The summary features the top 3 asthma/small airways articles each month. The article above is a part of the project. The archive is here: http://www.worldallergy.org/small_airways_group/reviews/archive.php
Image source: Image source: FDA and Wikipedia, public domain.