title: Risk assessment of readmissions following an initial COPD-related hospitalization.
abstract: BACKGROUND
  Acute exacerbation of chronic obstructive pulmonary disease (COPD) is a leading cause of hospitalizations and readmissions in the US. Reducing the frequency of hospital readmission is a high priority of US health care organizations and government agencies. This study evaluated the risk factors associated with readmissions among commercially insured adults aged 40-65 years in the US who were hospitalized for COPD.
  
  
  METHODS
  This retrospective cohort study used anonymized claims data from the Truven Health MarketScan® Commercial Claims and Encounters database. The patients included were aged 40-65 years, had an index hospitalization with a primary diagnosis of COPD between July 1, 2008 and June 30, 2010 (continuously enrolled 12 months before and after), and were alive at hospital discharge. Patients with cystic fibrosis or tuberculosis or who were transferred to another inpatient facility after hospital discharge were excluded. All readmissions regardless of diagnosis, and separately a subset of all readmissions that had COPD as a primary or secondary diagnosis (COPD-related), were examined. Univariate descriptive statistics and multivariable regression methods were used.
  
  
  RESULTS
  Of the 18,568 patients with index COPD hospitalizations, 6,095 (32.83%) met the eligibility criteria. Of those, 503 (8.25%) were readmitted within the first 30 days post-index hospitalization and 2,527 (41.46%) within the first year (COPD-related 340 [5.58%] and 1,681 [27.58%], respectively). The median time to the first readmission post initial discharge was 4.0 months, with a mean of 5.0 ± 3.4 months. Multivariable regression analyses showed that comorbid conditions and health care utilization in the pre-index period were significant predictors for readmission both 30 and 90 days following index hospitalization.
  
  
  CONCLUSIONS
  A relatively high readmission rate was observed for patients aged 40-65 years. The results suggest that attention to patient comorbidities and pre-index/index health care service utilization may help identify hospitalized COPD patients at higher risk for readmission.
authors.affiliation: Pfizer Inc, New York, NY, USA.
authors.forename: Christine L
authors.initials: CL
authors.lastname: Baker
authors.affiliation: Pfizer Inc, New York, NY, USA.
authors.forename: Kelly H
authors.initials: KH
authors.lastname: Zou
authors.affiliation: Boehringer-Ingelheim Pharmaceuticals Inc, Ridgefield, CT, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Su
mesh_terms: D000328:Adult; D000368:Aged; D016009:Chi-Square Distribution; D015897:Comorbidity; D005260:Female; D006295:Health Resources / Q000706:statistics & numerical data; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D010359:Patient Readmission; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis / Q000628:therapy*; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D014481:United States
keywords: chronic obstructive pulmonary disease; claims data; hospitalization; noninterventional study; readmission; real-world data; rehospitalization