title: Complexity of medication use in newly diagnosed chronic obstructive pulmonary disease patients.
abstract: BACKGROUND
  To better understand how medications have been used and the complexity of regimens used to treat patients, we characterized patterns of medication use and the degree to which patients used different classes of medications in combination and over time in a cohort of newly diagnosed chronic obstructive pulmonary disease (COPD) patients.
  
  
  OBJECTIVE
  The objectives of this study were to characterize patterns of medication use, including the degree to which patients used different classes of medications in combination and over time within a cohort of newly diagnosed COPD patients and to identify the proportion of patients who had gaps in filling their prescriptions.
  
  
  METHODS
  We identified a cohort of patients from the Veterans Affairs health care system with newly diagnosed COPD between 1999 and 2003. Using prescription fill information, we quantified the prevalence and incidence of exposure to short-acting β-agonists (SABAs), long-acting β-agonists (LABAs), short-acting anticholinergics (eg, ipratropium [IPRA]), and inhaled corticosteroids (ICSs) over 1 year. We additionally characterized the sequencing of medication addition and discontinuation and gaps between prescription fills. The prevalence of multiple respiratory medication use was summarized at 90, 180, and 365 days of follow-up.
  
  
  RESULTS
  Of 133,737 patients with newly diagnosed COPD, the majority (80.0%) used a SABA, followed by 40.0% using IPRA, 33.2% using an ICS and 16.0% using a LABA during the 1-year follow-up. Medication changes were frequent, with 57.7% of patients having a medication addition and 48.6% discontinuing medication. The sequence of medication changes varied greatly across patients. Multiple respiratory medication use was common, with 29% of patients dispensed 3 to 4 medication classes in 1 year.
  
  
  CONCLUSIONS
  Many COPD patients who are started on medication management undergo changes in prescribed pharmacotherapy and are taking multiple medications. Despite clinical practice guidelines, there is an ad hoc nature of COPD medication management, and such heterogeneity challenges the ability to estimate relationships between drug exposure and outcomes using real-world data.
authors.affiliation: Center for Pharmacoeconomic Research, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois, USA.
authors.forename: Caitlyn T
authors.initials: CT
authors.lastname: Solem
authors.forename: Todd A
authors.initials: TA
authors.lastname: Lee
authors.forename: Min J
authors.initials: MJ
authors.lastname: Joo
authors.forename: Bruce L
authors.initials: BL
authors.lastname: Lambert
authors.forename: Surrey M
authors.initials: SM
authors.lastname: Walton
authors.forename: A Simon
authors.initials: AS
authors.lastname: Pickard
mesh_terms: D000368:Aged; D001993:Bronchodilator Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D015331:Cohort Studies; D004359:Drug Therapy, Combination; D005260:Female; D005500:Follow-Up Studies; D005938:Glucocorticoids / Q000008:administration & dosage / Q000627:therapeutic use; D006787:Hospitals, Veterans; D006801:Humans; D008297:Male; D008875:Middle Aged; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D029424:Pulmonary Disease, Chronic Obstructive / Q000188:drug therapy*; D013997:Time Factors; D014481:United States; D014493:United States Department of Veterans Affairs
chemical_list: D001993:Bronchodilator Agents; D005938:Glucocorticoids