title: Effects of inhaled versus systemic corticosteroids on exhaled nitric oxide in severe acute asthma.
abstract: BACKGROUND
  There is a paucity of information on the differential effects of systemic versus inhaled corticosteroids on airway inflammation in patients with acute asthma. This study aimed to evaluate the effects of stopping systemic corticosteroids while maintaining the inhaled corticosteroids (ICS) on airway inflammation, lung function and asthma symptoms in patients who had been discharged from hospital after treatment for severe acute asthma.
  
  
  METHODS
  Twenty-four adult patients with severe exacerbations of asthma were treated with both oral and inhaled corticosteroids after discharge from hospital. Oral corticosteroids were stopped after 1 week. Spirometry, asthma quality of life questionnaire (AQLQ) score and exhaled nitric oxide (NO) were measured at discharge, 1 week, and 2 weeks after discharge.
  
  
  RESULTS
  Withdrawal of oral corticosteroids resulted in significant rebound in mean exhaled NO by 11.0ppb (95% CI, 4.9-17.1ppb, p<0.001) or 47.7% (95% CI, 22.4-73.1%) despite uninterrupted ICS treatment. The rebound in exhaled NO occurred despite significant improvement in the mean AQLQ score (p=0.006) and frequency of reliever use (p=0.003) and was not associated with significant change in the mean FEV(1) (p=0.64).
  
  
  CONCLUSIONS
  In patients discharged from hospital after treatment for asthma exacerbations, withdrawal of oral corticosteroids resulted in increase in exhaled NO levels despite continued ICS treatment.
authors.affiliation: Division of Respiratory and Critical Care Medicine, National University Hospital, Singapore, Singapore. KhooSM@nuh.com.sg
authors.forename: See Meng
authors.initials: SM
authors.lastname: Khoo
authors.forename: T K
authors.initials: TK
authors.lastname: Lim
mesh_terms: D000208:Acute Disease; D000280:Administration, Inhalation; D000284:Administration, Oral; D000293:Adolescent; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage*; D000328:Adult; D000368:Aged; D001249:Asthma / Q000188:drug therapy*; D001944:Breath Tests; D005260:Female; D005541:Forced Expiratory Volume; D005938:Glucocorticoids / Q000008:administration & dosage; D006760:Hospitalization; D006801:Humans; D008297:Male; D008450:Maximal Midexpiratory Flow Rate; D008875:Middle Aged; D009569:Nitric Oxide / Q000378:metabolism*; D011239:Prednisolone / Q000008:administration & dosage; D011788:Quality of Life; D013147:Spirometry; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000305:Adrenal Cortex Hormones; D005938:Glucocorticoids; D009569:Nitric Oxide; D011239:Prednisolone