title: The economic burden of chronic obstructive pulmonary disease (COPD) in a U.S. Medicare population.
abstract: BACKGROUND
  Although the economic burden of COPD has gained attention in recent years, data on the costs of COPD among U.S. Medicare beneficiaries are lacking.
  
  
  METHODS
  This study used administrative claims and eligibility records from a large U.S. multi-state Medicare managed care database. Study patients were 65+ years of age with paid claims during 2004. The COPD cohort comprised patients with 1+ inpatient/ER claims or 2+ outpatient claims (>30 days apart) for COPD (ICD-9-CM codes 491.xx, 492.x, 496). The comparison cohort included patients without COPD matched 3:1 to the COPD cohort on age, sex, enrollment months, and Medicare plan. Excess costs of COPD were estimated as the difference in overall health plan payments between the two cohorts during 2004. Attributable costs were calculated using medical claims with listed diagnoses of COPD or other respiratory-related conditions and pharmacy claims for respiratory medications.
  
  
  RESULTS
  A total of 8370 patients were included in the COPD cohort and were matched to 25,110 comparison cohort patients. For both groups, mean (SD) age was 78 (8) years, 54% were female, and duration of eligibility was 11 (2) months. COPD patients were more likely to utilize healthcare services and had excess total healthcare costs about $20,500 higher (P<0.0001) than the comparison cohort. Comorbidities were high in the COPD cohort, accounting for 46% of the observed excess cost. The attributable cost of COPD averaged about $6,300; other respiratory-related costs averaged about $4,400.
  
  
  CONCLUSIONS
  In this U.S. Medicare managed care population, COPD posed a substantial burden in terms of both respiratory-related and total healthcare costs. A comparison of these cost-of-illness estimates to those for elderly COPD patients in other countries would be of great interest, given the increasing age of populations in most Western countries.
authors.affiliation: Boston Health Economics, Inc., 20 Fox Road, Waltham, MA 02451, USA. jmenzin@bhei.com
authors.forename: Joseph
authors.initials: J
authors.lastname: Menzin
authors.forename: Luke
authors.initials: L
authors.lastname: Boulanger
authors.forename: Jeno
authors.initials: J
authors.lastname: Marton
authors.forename: Lisa
authors.initials: L
authors.lastname: Guadagno
authors.forename: Homa
authors.initials: H
authors.lastname: Dastani
authors.forename: Riad
authors.initials: R
authors.lastname: Dirani
authors.forename: Amy
authors.initials: A
authors.lastname: Phillips
authors.forename: Hemal
authors.initials: H
authors.lastname: Shah
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D015897:Comorbidity; D004180:Direct Service Costs; D016527:Drug Costs; D005260:Female; D017048:Health Care Costs; D006760:Hospitalization / Q000191:economics; D006801:Humans; D016018:Least-Squares Analysis; D008297:Male; D006278:Medicare / Q000191:economics*; D010342:Patient Acceptance of Health Care / Q000706:statistics & numerical data; D029424:Pulmonary Disease, Chronic Obstructive / Q000191:economics*; D014481:United States