title: The clinical and economic impact of exacerbations of chronic obstructive pulmonary disease: a cohort of hospitalized patients.
abstract: BACKGROUND
  Chronic Obstructive Pulmonary Disease (COPD) is a common disease with significant health and economic consequences. This study assesses the burden of COPD in the general population, and the influence of exacerbations (E-COPD) on disease progression and costs.
  
  
  METHODS
  This is a secondary data analysis of healthcare administrative databases of the region of Lombardy, in northern Italy. The study included ≥ 40 year-old patients hospitalized for a severe E-COPD (index event) during 2006. Patients were classified in relation to the number and type of E-COPD experienced in a three-year pre-index period. Subjects were followed up until December 31st, 2009, collecting data on healthcare resource use and vital status.
  
  
  RESULTS
  15857 patients were enrolled -9911 males, mean age: 76 years (SD 10). Over a mean follow-up time of 2.4 years (1.36), 81% of patients had at least one E-COPD with an annual rate of 3.2 exacerbations per person-year and an all-cause mortality of 47%. A history of exacerbation influenced the occurrence of new E-COPD and mortality after discharge for an E-COPD. On average, the healthcare system spent 6725€ per year per person (95%CI 6590-6863). Occurrence and type of exacerbations drove the direct healthcare cost. Less than one quarter of patients presented claims for pulmonary function tests.
  
  
  CONCLUSIONS
  COPD imposes a substantial burden on healthcare systems, mainly attributable to the type and occurrence of E-COPD, or in other words, to the exacerbator phenotypes. A more tailored approach to the management of COPD patients is required.
authors: Department of Pathophysiology and Transplantation, Università degli Studi di Milano, IRCCS Fondazione Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy.
authors: Francesco
authors: F
authors: Blasi
authors: CESP, Research Centre on Public Health, Department of Statistics and Quantitative Methods, University of Milano - Bicocca, Monza, Italy.
authors: Giancarlo
authors: G
authors: Cesana
authors: CESP, Research Centre on Public Health, Department of Statistics and Quantitative Methods, University of Milano - Bicocca, Monza, Italy.
authors: Sara
authors: S
authors: Conti
authors: CESP, Research Centre on Public Health, Department of Statistics and Quantitative Methods, University of Milano - Bicocca, Monza, Italy.
authors: Virginio
authors: V
authors: Chiodini
authors: Department of Health Sciences, University of Milano - Bicocca, Respiratory Unit, AO San Gerardo, Monza, Italy.
authors: Stefano
authors: S
authors: Aliberti
authors: CESP, Research Centre on Public Health, Department of Statistics and Quantitative Methods, University of Milano - Bicocca, Monza, Italy.
authors: Carla
authors: C
authors: Fornari
authors: CESP, Research Centre on Public Health, Department of Statistics and Quantitative Methods, University of Milano - Bicocca, Monza, Italy; University of Napoli Federico II, Naples, Italy.
authors: Lorenzo Giovanni
authors: LG
authors: Mantovani
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D005260:Female; D006760:Hospitalization / Q000191:economics* / Q000706:statistics & numerical data; D006801:Humans; D007297:Inpatients / Q000706:statistics & numerical data*; D008297:Male; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications* / Q000191:economics / Q000453:epidemiology