title: The use of multiple respiratory inhalers requiring different inhalation techniques has an adverse effect on COPD outcomes.
abstract: BACKGROUND
  Patients with COPD may be prescribed multiple inhalers as part of their treatment regimen, which require different inhalation techniques. Previous literature has shown that the effectiveness of inhaled treatment can be adversely affected by incorrect inhaler technique. Prescribing a range of device types could worsen this problem, leading to poorer outcomes in COPD patients, but the impact is not yet known.
  
  
  OBJECTIVE
  To compare clinical outcomes of COPD patients who use devices requiring similar inhalation technique with those who use devices with mixed techniques.
  
  
  METHODS
  A matched cohort design was used, with 2 years of data from the Optimum Patient Care Research Database. Matching variables were established from a baseline year of follow-up data, and two cohorts were formed: a "similar-devices cohort" and a "mixed-devices cohort". COPD-related events were recorded during an outcome year of follow-up. The primary outcome measure was an incidence rate ratio (IRR) comparing the rate of exacerbations between study cohorts. A secondary outcome compared average daily use of short-acting beta agonist (SABA).
  
  
  RESULTS
  The final study sample contained 8,225 patients in each cohort (mean age 67 [SD, 10], 57% males, 37% current smokers). Patients in the similar-devices cohort had a lower rate of exacerbations compared with those in the mixed-devices cohort (adjusted IRR 0.82, 95% confidence interval [CI] 0.80-0.84) and were less likely to be in a higher-dose SABA group (adjusted proportional odds ratio 0.54, 95% CI 0.51-0.57).
  
  
  CONCLUSIONS
  COPD patients who were prescribed one or more additional inhaler devices requiring similar inhalation techniques to their previous device(s) showed better outcomes than those who were prescribed devices requiring different techniques.
authors.affiliation: Woolcock Institute of Medical Research, School of Medical Sciences, University of Sydney and Sydney Local Health District, Sydney, NSW, Australia.
authors.forename: Sinthia
authors.initials: S
authors.lastname: Bosnic-Anticevich
authors.affiliation: Observational and Pragmatic Research Institute Pte Ltd, Singapore.
authors.forename: Henry
authors.initials: H
authors.lastname: Chrystyn
authors.affiliation: RCSI Medicine, Royal College of Surgeons; RCSI Education & Research Centre, Beaumont Hospital, Beaumont, Dublin, Ireland.
authors.forename: Richard W
authors.initials: RW
authors.lastname: Costello
authors.affiliation: Department of Medicine, Respirology, McMaster University, ON, Canada.
authors.forename: Myrna B
authors.initials: MB
authors.lastname: Dolovich
authors.affiliation: Education for Health, Warwick, UK.
authors.forename: Monica J
authors.initials: MJ
authors.lastname: Fletcher
authors.affiliation: Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.
authors.forename: Federico
authors.initials: F
authors.lastname: Lavorini
authors.affiliation: Respiratory Institute, Hospital Clinic, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Roberto
authors.initials: R
authors.lastname: Rodríguez-Roisin
authors.affiliation: Optimum Patient Care, Cambridge; Centre for Population Health Sciences, University of Edinburgh, Edinburgh.
authors.forename: Dermot
authors.initials: D
authors.lastname: Ryan
authors.affiliation: Observational and Pragmatic Research Institute Pte Ltd, Singapore.
authors.forename: Simon
authors.initials: S
authors.lastname: Wan Yau Ming
authors.affiliation: Observational and Pragmatic Research Institute Pte Ltd, Singapore; Academic Primary Care, University of Aberdeen, Aberdeen, UK.
authors.forename: David B
authors.initials: DB
authors.lastname: Price
mesh_terms: D000280:Administration, Inhalation; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001993:Bronchodilator Agents / Q000008:administration & dosage*; D016208:Databases, Factual; D004334:Drug Administration Schedule; D004338:Drug Combinations; D004359:Drug Therapy, Combination; D004867:Equipment Design; D005260:Female; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D016014:Linear Models; D016015:Logistic Models; D008168:Lung / Q000187:drug effects* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009330:Nebulizers and Vaporizers; D017711:Nonlinear Dynamics; D016017:Odds Ratio; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology / Q000523:psychology; D012307:Risk Factors; D012648:Self Care; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D001993:Bronchodilator Agents; D004338:Drug Combinations
keywords: chronic obstructive pulmonary disease; exacerbations; inhalation technique; inhaler devices; matched cohort; observational