title: Mortality and severity evaluation by routine pneumonia prediction models among Japanese patients with 2009 pandemic influenza A (H1N1) pneumonia.
abstract: BACKGROUND
  Influenza-related pneumonia, referred to as influenza pneumonia, was reported relatively more frequently during a recent influenza pandemic in 2009. The validity of adapting routine pneumonia severity prediction models for various types of pneumonia is unclear.
  
  
  METHODS
  We conducted a nationwide survey to evaluate influenza pneumonia among adult patients in Japan. Questionnaires were sent to physicians working in departments of respiratory medicine at 2491 hospitals. Both the outcome and pneumonia severity, using invasive positive pressure ventilation (IPPV) as an indicator, were evaluated by routine pneumonia severity index (PSI), CURB-65 (confusion, urea, respiratory rate, blood pressure, and age ≥ 65 years), and A-DROP (age, dehydration, respiration, disorientation, and blood pressure).
  
  
  RESULTS
  Data collected from 320 patients with influenza pneumonia, including 25 cases (7.8%) of death and 43 (13.4%) of IPPV, were analyzed. Although all routine prediction models showed that higher mortality tended to be associated with a higher risk class/grade, the actual mortality rates were higher than predicted. The risk class of mortality calculated by the PSI was influenced by pneumonia patterns. Although pneumonia severity was similarly predicted, the types of pneumonia also affected severity in all prediction models. A-DROP showed the highest accuracy on receiver operating characteristic analysis for both mortality and severity.
  
  
  CONCLUSIONS
  CURB-65 and A-DROP are fair predictors of mortality regardless of pneumonia patterns. However, the current pneumonia prediction models may underestimate the severity and appropriate site of care for patients with influenza pneumonia.
authors.affiliation: Division of Infectious Diseases and Respiratory Medicine, Department of Internal Medicine, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama 359-8513, Japan. Electronic address: fujikura@ndmc.ac.jp.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Fujikura
authors.affiliation: Division of Infectious Diseases and Respiratory Medicine, Department of Internal Medicine, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama 359-8513, Japan. Electronic address: DRI2438@ndmc.ac.jp.
authors.forename: Shuichi
authors.initials: S
authors.lastname: Kawano
authors.affiliation: Division of Infectious Diseases and Respiratory Medicine, Department of Internal Medicine, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama 359-8513, Japan. Electronic address: dri2443@ndmc.ac.jp.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Kouzaki
authors.affiliation: Respiratory Disease Center, Yokohama City University Medical Center, 4-57 Urafunecho, Minami-ku, Yokohama, Kanagawa 232-0024, Japan. Electronic address: smarou@yokohama-cu.ac.jp.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Shinoda
authors.affiliation: Division of Infectious Diseases and Respiratory Medicine, Department of Internal Medicine, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama 359-8513, Japan. Electronic address: bronchiole0723@yahoo.co.jp.
authors.forename: Yu
authors.initials: Y
authors.lastname: Hara
authors.affiliation: Respiratory Disease Center, Yokohama City University Medical Center, 4-57 Urafunecho, Minami-ku, Yokohama, Kanagawa 232-0024, Japan. Electronic address: shinkai@yokohama-cu.ac.jp.
authors.forename: Masaharu
authors.initials: M
authors.lastname: Shinkai
authors.affiliation: Division of Infectious Diseases and Respiratory Medicine, Department of Internal Medicine, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama 359-8513, Japan. Electronic address: kanoh@ndmc.ac.jp.
authors.forename: Soichiro
authors.initials: S
authors.lastname: Kanoh
authors.affiliation: Division of Infectious Diseases and Respiratory Medicine, Department of Internal Medicine, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama 359-8513, Japan. Electronic address: kawana59@ndmc.ac.jp.
authors.forename: Akihiko
authors.initials: A
authors.lastname: Kawana
mesh_terms: D000367:Age Factors; D015331:Cohort Studies; D004196:Disease Outbreaks; D005260:Female; D005544:Forecasting; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype; D007251:Influenza, Human / Q000453:epidemiology* / Q000401:mortality; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D011024:Pneumonia, Viral / Q000453:epidemiology* / Q000401:mortality; D012372:ROC Curve; D012189:Retrospective Studies; D012306:Risk; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D015996:Survival Rate; D013997:Time Factors
keywords: A-DROP; CURB-65; Influenza; Influenza pneumonia; Pneumonia severity index