title: Temporal trends in hospitalization rates for older adults with chronic obstructive pulmonary disease.
abstract: BACKGROUND
  Over the last 15 years, substantial advances have been made in the treatment of chronic obstructive pulmonary disease (COPD). Little information is available, however, on whether these treatments have resulted in reduced rates of hospitalization and acute exacerbations among COPD patients. This retrospective cohort study examined changes in hospitalization rates among Medicare beneficiaries with COPD from 1999 to 2008.
  
  
  METHODS
  We analyzed data from 424,418 fee-for-service Medicare beneficiaries enrolled between 1999 and 2008 who were diagnosed with COPD. We examined temporal changes in the frequency of hospitalization and acute exacerbations among Medicare beneficiaries with COPD.
  
  
  RESULTS
  Over the 10-year study period, the hospitalization rates for COPD patients--adjusted for age, sex, race, socioeconomic status, region, and number of comorbidities--decreased: from 131 to 107 per 100 person-years for all causes (P <.001); from 58 to 44 per 100 person-years for all respiratory causes (P <.001); and from 73 to 63 per 100 person-years for nonrespiratory causes (P <.001). There was no change in prevalence of COPD in the Medicare population over this time. Additionally, the percentage of COPD patients hospitalized with 2 or more acute exacerbations decreased from 5.5% to 4.3% over the 10-year study period (P <.001).
  
  
  CONCLUSIONS
  Between 1999 and 2008, hospitalization rates decreased substantially among Medicare beneficiaries diagnosed with COPD.
authors.affiliation: Department of Preventive Medicine and Community Health, University of Texas Medical Branch, Galveston, TX 77555, USA. jbaillar@utmb.edu
authors.forename: Jacques
authors.initials: J
authors.lastname: Baillargeon
authors.forename: Yue
authors.initials: Y
authors.lastname: Wang
authors.forename: Yong-Fang
authors.initials: YF
authors.lastname: Kuo
authors.forename: Holly M
authors.initials: HM
authors.lastname: Holmes
authors.forename: Gulshan
authors.initials: G
authors.lastname: Sharma
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D015331:Cohort Studies; D018450:Disease Progression; D005260:Female; D006760:Hospitalization / Q000639:trends*; D006801:Humans; D008297:Male; D006278:Medicare / Q000639:trends; D016012:Poisson Distribution; D015995:Prevalence; D029424:Pulmonary Disease, Chronic Obstructive / Q000453:epidemiology*; D012189:Retrospective Studies; D014481:United States / Q000453:epidemiology