title: Association between prescribing patterns of anti-asthmatic drugs and clinically uncontrolled asthma: a cross-sectional study.
abstract: OBJECTIVE
  Studies based on prescription data have shown that many asthmatics tend to use large quantities of inhaled beta-2-agonists, suggesting poorly controlled disease. The aim of the present study was to investigate the association between clinically uncontrolled asthma and prescribing patterns of anti-asthmatic drugs with a primary focus on short-acting beta-2-agonists (SABA).
  
  
  METHODS
  In a cross-sectional study 357 subjects, selected by their prescriptions of inhaled beta-2-agonists in Odense Pharmaco-Epidemiological Database, underwent individual clinical assessment including the Asthma Control Questionnaire (ACQ) and spirometry. The associations between uncontrolled asthma (ACQ score ≥ 1.50) and individual anti-asthmatic prescribing were analysed by means of logistic regression.
  
  
  RESULTS
  Clinically uncontrolled asthma was positively associated with SABA use, the association becoming stronger with higher annual quantity of SABA use, odds ratio (OR) 11.1 (95% CI 4.4-28.0) for ≥400 DDD/year. This trend persisted after stratifying for gender, age, and controller treatment. Although subjects using ≥450 DDD/year were all uncontrolled, there was substantial overlap in SABA use between controlled and uncontrolled subjects below this limit. We found no effect modification by age and gender. Use of inhaled corticosteroids protected against uncontrolled asthma, OR 0.51 (95% CI 0.27-0.95).
  
  
  CONCLUSIONS
  Asthmatics with a high use of SABA frequently have problems with uncontrolled asthma, and users of ICS are protected against uncontrolled asthma. The associations we found were, however, to weak too allow firm conclusions about asthma control for most individual asthma patients.
authors.affiliation: Research Unit of General Practice, Institute of Public Health, University of Southern Denmark. jrd@dadlnet.dk
authors.forename: Jesper Rømhild
authors.initials: JR
authors.lastname: Davidsen
authors.forename: Jesper
authors.initials: J
authors.lastname: Hallas
authors.forename: Jens
authors.initials: J
authors.lastname: Søndergaard
authors.forename: René Depont
authors.initials: RD
authors.lastname: Christensen
authors.forename: Hans Christian
authors.initials: HC
authors.lastname: Siersted
authors.forename: Malene Plejdrup
authors.initials: MP
authors.lastname: Hansen
authors.forename: Thomas Bøllingtoft
authors.initials: TB
authors.lastname: Knudsen
authors.forename: Jesper
authors.initials: J
authors.lastname: Lykkegaard
authors.forename: Morten
authors.initials: M
authors.lastname: Andersen
mesh_terms: D000293:Adolescent; D058666:Adrenergic beta-2 Receptor Agonists / Q000627:therapeutic use*; D000328:Adult; D018927:Anti-Asthmatic Agents / Q000627:therapeutic use*; D001249:Asthma / Q000188:drug therapy*; D003430:Cross-Sectional Studies; D004363:Drug Utilization; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male
chemical_list: D058666:Adrenergic beta-2 Receptor Agonists; D018927:Anti-Asthmatic Agents