title: A systematic review of long-acting β2-agonists versus higher doses of inhaled corticosteroids in asthma.
abstract: OBJECTIVE
  To compare the efficacy of inhaled corticosteroids (ICS) plus long-acting β2 agonist (LABA) versus higher doses of ICS in children/adolescents with uncontrolled persistent asthma.
  
  
  METHODS
  Randomized, prospective, controlled trials published January 1996 to January 2012 with a minimum of 4 weeks of LABA+ICS versus higher doses of ICS were retrieved through Medline, Embase, Central, and manufacturer's databases. The primary outcome was asthma exacerbations requiring systemic corticosteroids; secondary outcomes were the pulmonary function test (PEF), withdrawals during the treatment period, days without symptoms, use of rescue medication, and adverse events.
  
  
  RESULTS
  Nine studies (n = 1641 patients) met criteria for inclusion (7 compared LABA+ICS versus double ICS doses and 2 LABA+ICS versus higher than double ICS doses). There was no statistically significant difference in the number of patients with asthma exacerbations requiring systemic corticosteroids between children receiving LABA+ICS and those receiving higher doses of ICS (odds ratio = 0.76; 95% confidence interval: 0.48-1.22, P = .25, I(2) = 16%). In the subgroup analysis, patients receiving LABA+ICS showed a decreased risk of asthma exacerbations compared with higher than twice ICS doses (odds ratio = 0.48; 95% confidence interval: 0.28-0.82, P = .007, I(2)= 0). Children treated with LABA+ICS had significantly higher PEF, less use of rescue medication, and higher short-term growth than those on higher ICS doses. There were no other significant differences in adverse events.
  
  
  CONCLUSIONS
  There were no statistically significant group differences between ICS+LABA and double doses of ICS in reducing the incidence of asthma exacerbations but it did decrease the risk comparing to higher than double doses of ICS.
authors.affiliation: Department of Family Medicine, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile. jacastro17@hotmail.com
authors.forename: Jose A
authors.initials: JA
authors.lastname: Castro-Rodriguez
authors.forename: Gustavo J
authors.initials: GJ
authors.lastname: Rodrigo
mesh_terms: D000280:Administration, Inhalation; D000318:Adrenergic beta-Agonists / Q000008:administration & dosage*; D018927:Anti-Asthmatic Agents / Q000008:administration & dosage*; D001249:Asthma / Q000188:drug therapy*; D002648:Child; D003692:Delayed-Action Preparations; D005260:Female; D005938:Glucocorticoids / Q000008:administration & dosage*; D006801:Humans; D008297:Male
chemical_list: D000318:Adrenergic beta-Agonists; D018927:Anti-Asthmatic Agents; D003692:Delayed-Action Preparations; D005938:Glucocorticoids