title: A rapid staging system for predicting mortality from HIV-associated community-acquired pneumonia.
abstract: OBJECTIVE
  Community-acquired pneumonia (CAP) accounts for an increasing proportion of the pulmonary infections in individuals with HIV infection. During the mid-1990s, hospital mortality rates for HIV-associated CAP ranged from 0 to 28%. While hospital differences in case mix may account for mortality rate variation, few methods to evaluate illness severity for HIV-associated CAP have been reported previously. The study objective was to develop a staging system for categorizing mortality risk of patients with HIV-associated CAP using information available prior to hospital admission.
  
  
  METHODS
  Retrospective medical records review of 1,415 patients hospitalized with HIV-associated CAP from 1995 to 1997 at 86 hospitals in seven metropolitan areas.
  
  
  METHODS
  In-patient mortality rate.
  
  
  RESULTS
  Hierarchically optimal classification tree analysis was used to develop a preadmission staging system for predicting inpatient mortality. The overall inpatient mortality rate was 9.1%. The significant predictors of mortality included the presence of neurologic symptoms, respiratory rate > or = 25 breaths/min, and creatinine > 1.2 mg/dL. The model identified a five-category staging system, with the mortality rate increasing by stage: 2.3% for stage 1, 5.8% for stage 2, 12.9% for stage 3, 22.0% for stage 4, and 40.5% for stage 5. The classification accuracy of the model was 85.2%.
  
  
  CONCLUSIONS
  Our staging system categorizes inpatient mortality risk for patients with HIV-associated CAP using three routinely available variables. The staging system may be useful for guiding clinical decisions about the intensity of patient care and for case-mix adjustment in future studies addressing variation in hospital mortality rates.
authors.affiliation: VA Chicago Healthcare System, Westside Division, Department of Medicine, University of Illinois College of Medicine, 60612, USA. arozulla@uic.edu
authors.forename: Ahsan M
authors.initials: AM
authors.lastname: Arozullah
authors.forename: Jorge
authors.initials: J
authors.lastname: Parada
authors.forename: Charles L
authors.initials: CL
authors.lastname: Bennett
authors.forename: Maria
authors.initials: M
authors.lastname: Deloria-Knoll
authors.forename: Joan S
authors.initials: JS
authors.lastname: Chmiel
authors.forename: Laura
authors.initials: L
authors.lastname: Phan
authors.forename: Paul R
authors.initials: PR
authors.lastname: Yarnold
mesh_terms: D017088:AIDS-Related Opportunistic Infections / Q000401:mortality*; D000328:Adult; D017714:Community-Acquired Infections; D005260:Female; D015658:HIV Infections / Q000401:mortality*; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D015233:Models, Statistical; D015999:Multivariate Analysis; D011024:Pneumonia, Viral / Q000401:mortality*; D012189:Retrospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index