title: Salmeterol use and risk of hospitalization among emergency department patients with acute asthma.
abstract: BACKGROUND
  The safety of inhaled long-acting beta2-agonists (LABAs) in the treatment of chronic asthma remains controversial and has not been evaluated in emergency department (ED) patients with acute asthma.
  
  
  OBJECTIVE
  To determine whether ED patients undergoing long-term LABA therapy would have increased risk of asthma-related hospitalization compared with those not undergoing LABA therapy and whether concurrent long-term inhaled corticosteroid (ICS) therapy would mitigate this risk.
  
  
  METHODS
  Prospective cohort study of patients aged 12 to 54 years with acute asthma in 115 EDs. Four patient groups were created based on their asthma regimen: no ICS or salmeterol (group A), salmeterol monotherapy (group B), ICS monotherapy (group C), and combination ICS and salmeterol (group D).
  
  
  RESULTS
  Of the 2,236 included patients, group A had 1,221 patients (55%), group B had 48 patients (2%), group C had 787 patients (35%), and group D had 180 patients (8%); 489 patients (22%) required hospitalization. In a multivariable model controlling for 20 factors and using group A as the reference, group B had an increased risk of hospitalization (odds ratio [OR], 2.2; 95% confidence interval [CI], 1.0-4.9), whereas groups C (OR, 1.1; 95% CI, 0.8-1.5) and D (OR, 1.2; 95% CI, 0.8-1.9) did not.
  
  
  CONCLUSIONS
  Among ED patients with acute asthma, those undergoing salmeterol monotherapy had an increased risk of hospitalization; however, this risk was not seen among patients undergoing combination ICS-salmeterol therapy. Our findings provide data from a unique ED population on clinical response to acute asthma treatment among patients undergoing long-term LABA therapy.
authors.affiliation: Department of Emergency Medicine, Denver Health Medical Center, Denver, Colorado, USA.
authors.forename: Michael M
authors.initials: MM
authors.lastname: Liao
authors.forename: Adit A
authors.initials: AA
authors.lastname: Ginde
authors.forename: Sunday
authors.initials: S
authors.lastname: Clark
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Camargo
mesh_terms: D000208:Acute Disease; D000280:Administration, Inhalation; D000293:Adolescent; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage; D000318:Adrenergic beta-Agonists / Q000009:adverse effects*; D000328:Adult; D000420:Albuterol / Q000009:adverse effects / Q000031:analogs & derivatives*; D001249:Asthma / Q000188:drug therapy*; D002648:Child; D015331:Cohort Studies; D004630:Emergencies; D005260:Female; D006760:Hospitalization; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D000068299:Salmeterol Xinafoate
chemical_list: D000305:Adrenal Cortex Hormones; D000318:Adrenergic beta-Agonists; D000068299:Salmeterol Xinafoate; D000420:Albuterol