title: Prognostic impact of the Charlson comorbidity index on mortality following acute pulmonary embolism.
abstract: OBJECTIVE
  It was the aim of this study to determine the prognostic significance of the Charlson Comorbidity Index (CCI) following acute pulmonary embolism (PE) and assess the prognosis of patients without comorbidities (defined as a CCI score of 0).
  
  
  METHODS
  Outcomes of 1,023 consecutive patients admitted with confirmed PE were tracked after a median of 3.7 years (25-75th interquartile range 1.5-6.1 years). All were assigned a non-age-adjusted CCI score.
  
  
  RESULTS
  The median CCI score was 1.0 (interquartile range 0.0-3.0). Three hundred and fifty-one (34%) patients had a CCI score of 0. Only 1 (0.3%) of 31 in-hospital deaths occurred in patients with a CCI score of 0. Long-term mortality for these patients was similar to the population-derived age- and sex-matched mortality rate, and was significantly better than for those with a CCI score ≥1 (12.5 vs. 47.5%; p < 0.0001 adjusted for age and sex). In multivariate analysis, CCI (per 1-score increase) independently predicted in-hospital (hazard ratio 1.27, 95% confidence interval 1.09-1.49; p = 0.003) and post-discharge (hazard ratio 1.35, 95% confidence interval 1.29-1.42; p < 0.0001) death. The c statistics for the multivariate prediction models for in-hospital (incorporating CCI score and serum sodium level) and post-discharge death (age, CCI score, hyperlipidemia, serum sodium and hemoglobin) were 0.738 and 0.788, respectively (both p < 0.0001).
  
  
  CONCLUSIONS
  The CCI can be incorporated into risk models, with good discriminatory power, for predicting in-hospital and long-term outcomes following acute PE. Patients with a CCI score of 0 have a favorable long-term outcome following acute PE.
authors.affiliation: Cardiology Department, Concord Hospital, The University of Sydney, Concord, NSW, Australia. chin.ng@sydney.edu.au
authors.forename: Austin Chin Chwan
authors.initials: AC
authors.lastname: Ng
authors.forename: Vincent
authors.initials: V
authors.lastname: Chow
authors.forename: Andy Sze Chiang
authors.initials: AS
authors.lastname: Yong
authors.forename: Tommy
authors.initials: T
authors.lastname: Chung
authors.forename: Leonard
authors.initials: L
authors.lastname: Kritharides
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001315:Australia / Q000453:epidemiology; D015331:Cohort Studies; D015897:Comorbidity; D005260:Female; D006305:Health Status Indicators; D017052:Hospital Mortality; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011379:Prognosis; D016016:Proportional Hazards Models; D011655:Pulmonary Embolism / Q000175:diagnosis / Q000453:epidemiology / Q000628:therapy; D018570:Risk Assessment; D013997:Time Factors; D016896:Treatment Outcome