title: Inhaler devices in asthma and COPD--an assessment of inhaler technique and patient preferences.
abstract: BACKGROUND
  Incorrect use of inhaler devices remains an obstacle for respiratory diseases management. We aimed to evaluate the frequency of inhaler technique errors; to determine the devices perceived as the easiest and favourite to use; to study the association of device type, demographics and patient preferences with inhaler technique (IT).
  
  
  METHODS
  Cross-sectional assessment of 301 adults, with asthma (194) or chronic pulmonary obstructive disease, undergoing treatment with Aerolizer®, Autohaler®, Breezehaler®, Diskus®, Handihaler®, MDI without spacer, Miat-haler®, Novolizer®, Respimat® and/or Turbohaler®. Patients completed self-assessment questionnaires and face-to-face interview, with demonstration of inhaler technique. The rate of wrong steps (number of wrong steps ÷ number of total steps; RWS) was the primary outcome. Adjusted odds ratio (aOR) (95% confidence intervals [CI]) for presenting ≥1 IT errors were computed.
  
  
  RESULTS
  From the 464 inhaler technique performances, the median RWS was 18%. Turbohaler® (21%) and Diskus® (19%) were chosen as easiest and Novolizer® (18%), Diskus® (18%), Turbohaler® (17%) as favourite for daily use. Females (aOR 2.68 [95% CI 1.55-4.65]; vs. males], patients with >64 yr (aOR 2.73 [95% CI 1.15-6.48]; vs <45 yr) and patients using Aerolizer® or Handihaler® (aOR 3.24 [95% CI 1.13-9.32] and aOR 3.71 [95% CI 1.38-10.2], respectively) were more likely to perform IT errors; otherwise, no association was found, including with using the favourite device (aOR 1.43 [95% CI 0.84-2.42]).
  
  
  CONCLUSIONS
  The frequency of inhaler technique errors was high and no device was clearly preferred over the others. Using the preferred inhaler device was not associated with less errors.
authors.affiliation: Faculdade de Medicina da Universidade do Porto, Porto, Portugal.
authors.forename: Pedro
authors.initials: P
authors.lastname: Chorão
authors.affiliation: CIDES - Centro de Investigação em Tecnologias e Sistemas de Informação & CINTESIS, Faculdade de Medicina da Universidade do Porto, Porto, Portugal; Unidades de Imunoalergologia, CUF Porto, Porto, Portugal; Serviço de Imunoalergologia, Centro Hospitalar São João, Porto, Portugal.
authors.forename: Ana M
authors.initials: AM
authors.lastname: Pereira
authors.affiliation: CIDES - Centro de Investigação em Tecnologias e Sistemas de Informação & CINTESIS, Faculdade de Medicina da Universidade do Porto, Porto, Portugal; Unidades de Imunoalergologia, CUF Porto, Porto, Portugal. Electronic address: jfonseca@med.up.pt.
authors.forename: João A
authors.initials: JA
authors.lastname: Fonseca
mesh_terms: D000280:Administration, Inhalation; D000328:Adult; D000368:Aged; D001249:Asthma / Q000188:drug therapy* / Q000523:psychology; D003430:Cross-Sectional Studies; D004522:Educational Status; D004867:Equipment Design; D005260:Female; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D008297:Male; D008875:Middle Aged; D009330:Nebulizers and Vaporizers; D057240:Patient Preference; D011174:Portugal; D029424:Pulmonary Disease, Chronic Obstructive / Q000188:drug therapy*; D012646:Self Administration / Q000295:instrumentation / Q000592:standards
keywords: Asthma; COPD; Inhaler device; Inhaler technique; Patient preference