
15 publications were identified determining the prevalence of small airways disease in asthma. Methods of assessments included:
- impulse oscillometry
- spirometry
- body plethysmography
- multiple-breath nitrogen washout
- high-resolution computed tomography
The prevalence of small airways disease was 50-60% among patients with asthma. Small airways disease was present across all asthma severities, with evidence of distal airway disease even in the absence of proximal airway obstruction.
References:
The prevalence of small airways disease in adult asthma: A systematic literature review. Usmani OS et al. Respir Med. 2016 Jul;116:19-27. doi: 10.1016/j.rmed.2016.05.006. Epub 2016 May 7.
http://www.resmedjournal.com/article/S0954-6111(16)30082-8/fulltext
(free full text)
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
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