title: Small-airway disease in asthma: pharmacological considerations.
abstract: OBJECTIVE
  To review the pharmacological considerations and rationale for treating small-airway disease in asthma via the inhaled and systemic route, and to also directly address the comparison between small vs. large aerosol particles in the management of asthmatic patients.
  
  
  RESULTS
  Airway inflammation in patients with asthma is predominantly present within the small airways and this region is the main contributor to airflow limitation. Assessing small-airway dysfunction has advanced in the last decade, allowing us to compare this region in disease to health and also in response to treatment. Recent pharmaceutical developments have led to inhaler devices with smaller aerosols and systemic biologic treatments, enabling therapeutic drug delivery to the distal lung regions. The question therefore is does targeting the small airways directly translate into health benefits for asthmatic patients with respect to an improvement in their disease control and quality of life?
  
  
  CONCLUSIONS
  Studies now show that treating the peripheral airways with smaller drug particle aerosols certainly achieve comparable efficacy (and some studies show superiority) compared with large particles, a reduction in the daily inhaled corticosteroid dose, and greater asthma control and quality of life in real-life studies. Hence, the small airways should not be neglected when choosing the optimal asthma therapy.
authors.affiliation: Airway Disease Section, National Heart and Lung Institute, Imperial College London, Royal Brompton Hospital, London, UK.
authors.forename: Omar S
authors.initials: OS
authors.lastname: Usmani
mesh_terms: D000280:Administration, Inhalation; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage*; D000336:Aerosols; D000403:Airway Resistance / Q000187:drug effects*; D001249:Asthma / Q000188:drug therapy* / Q000503:physiopathology; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D006801:Humans; D007249:Inflammation / Q000188:drug therapy* / Q000503:physiopathology; D008168:Lung / Q000187:drug effects* / Q000503:physiopathology; D009330:Nebulizers and Vaporizers; D010316:Particle Size; D011788:Quality of Life
chemical_list: D000305:Adrenal Cortex Hormones; D000336:Aerosols