title: Air trapping in mild and moderate asthma: effect of inhaled corticosteroids.
abstract: BACKGROUND
  Air trapping reflects small airway obstruction in asthma and can be assessed quantitatively by high-resolution computed tomography (HRCT). Hydrofluoroalkane-beclomethasone dipropionate (HFA-BDP) is deposited across all sizes of airways, including the small ones. However, its long-term effect on air trapping remains unknown in uncontrolled asthma.
  
  
  OBJECTIVE
  To compare the effect of inhaled corticosteroids of different particle size - HFA-BDP and fluticasone propionate (FP) - on lung attenuation in mild-to-moderate uncontrolled asthma.
  
  
  METHODS
  A randomized study was performed to analyze the effect of HFA-BDP (400 microg/d) or FP (500 microg/d) given over a period of 3 months to patients with uncontrolled mild-to-moderate asthma. HRCT was performed with spirometric gating, and lung attenuation was measured at residual volume and at pulmonary total capacity. The difference between inspiratory and expiratory attenuation was calculated as an air trapping index.
  
  
  RESULTS
  Twenty-five out of 58 patients had abnormal air trapping and could be included in the study. Lung attenuation significantly diminished in the posterior zones of the lung after a 3-month treatment with HFA-BDP or FP, but the difference between the groups was not significant. Adjusted mean variations of the air trapping index from baseline to treatment completion were 34.3 (11.2, 57.3) and 27.3 (6.4, 48.2) for the HFA-BDP and FP groups, respectively. However, the reduction of air trapping area was more pronounced in the group treated with HFA-BDP.
  
  
  CONCLUSIONS
  Inhaled corticosteroids decrease air trapping in uncontrolled asthma regardless of their particle size.
  
  
  CONCLUSIONS
  In mild-to-moderate asthma, air trapping assessed by HRCT may be a new outcome related to the control of the disease.
authors.affiliation: Université Bordeaux 2, Institut National de la Santé et de la Recherche Medicale U885, Centre Hospitalier Universitaire (CHU) de Bordeaux, F-33076 Bordeaux, France. manuel.tunondelara@u-bordeaux2.fr
authors.forename: José-Manuel
authors.initials: JM
authors.lastname: Tunon-de-Lara
authors.forename: François
authors.initials: F
authors.lastname: Laurent
authors.forename: Violaine
authors.initials: V
authors.lastname: Giraud
authors.forename: Thierry
authors.initials: T
authors.lastname: Perez
authors.forename: Bernard
authors.initials: B
authors.lastname: Aguilaniu
authors.forename: Houari
authors.initials: H
authors.lastname: Meziane
authors.forename: Armelle
authors.initials: A
authors.lastname: Basset-Merle
authors.forename: Pascal
authors.initials: P
authors.lastname: Chanez
mesh_terms: D000280:Administration, Inhalation; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage / Q000627:therapeutic use; D000328:Adult; D000402:Airway Obstruction / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000209:etiology; D018927:Anti-Asthmatic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001249:Asthma / Q000150:complications / Q000000981:diagnostic imaging / Q000188:drug therapy*; D001507:Beclomethasone / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use*; D002000:Bronchospirometry; D005260:Female; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging; D008297:Male; D010316:Particle Size; D014057:Tomography, X-Ray Computed / Q000379:methods; D016896:Treatment Outcome
chemical_list: D000305:Adrenal Cortex Hormones; D018927:Anti-Asthmatic Agents; D001507:Beclomethasone