title: Elevated red cell distribution width predicts poor outcome in young patients with community acquired pneumonia.
abstract: BACKGROUND
  Community acquired pneumonia (CAP) is a major cause of morbidity and mortality. While there is much data about risk factors for severe outcome in the general population, there is less focus on younger group of patients. Therefore, we aimed to detect simple prognostic factors for severe morbidity and mortality in young patients with CAP.
  
  
  METHODS
  Patients of 60 years old or younger, who were diagnosed with CAP (defined as pneumonia identified 48 hours or less from hospitalization) between March 1, 2005 and December 31, 2008 were retrospectively analyzed for risk factors for complicated hospitalization and 90-day mortality.
  
  
  RESULTS
  The cohort included 637 patients. 90-day mortality rate was 6.6% and the median length of stay was 5 days. In univariate analysis, male patients and those with co-morbid conditions tended to have complicated disease. In multivariate analysis, variables associated with complicated hospitalization included post chest radiation state, prior neurologic damage, blood urea nitrogen (BUN) > 10.7 mmol/L and red cell distribution width (RDW) > 14.5%; whereas, variables associated with an increased risk of 90-day mortality included age ≥ 51 years, prior neurologic damage, immunosuppression, and the combination of abnormal white blood cells (WBC) and elevated RDW. Complicated hospitalization and mortality rate were significantly higher among patients with increased RDW regardless of the white blood cell count. Elevated RDW was associated with a significant increase in complicated hospitalization and 90-day mortality rates irrespective to hemoglobin levels.
  
  
  CONCLUSIONS
  In young patients with CAP, elevated RDW levels are associated with significantly higher rates of mortality and severe morbidity. RDW as a prognostic marker was unrelated with hemoglobin levels.
  
  
  BACKGROUND
  ClinicalTrials.Gov NCT00845312.
authors.affiliation: Department of Internal Medicine B, Rambam Health Care Campus, 1 Ha'aliya St, POB, 9602 Bat Galim, Haifa 31096, Israel.
authors.forename: Eyal
authors.initials: E
authors.lastname: Braun
authors.forename: Erel
authors.initials: E
authors.lastname: Domany
authors.forename: Yael
authors.initials: Y
authors.lastname: Kenig
authors.forename: Yoav
authors.initials: Y
authors.lastname: Mazor
authors.forename: Badira F
authors.initials: BF
authors.lastname: Makhoul
authors.forename: Zaher S
authors.initials: ZS
authors.lastname: Azzam
mesh_terms: D017714:Community-Acquired Infections / Q000097:blood / Q000401:mortality; D003428:Cross Infection / Q000097:blood*; D004909:Erythrocyte Indices; D004912:Erythrocytes / Q000502:physiology*; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007557:Israel / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D017063:Outcome Assessment, Health Care; D011014:Pneumonia / Q000097:blood* / Q000401:mortality*; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index