Emergency department crowding is associated with 28-day mortality in community-acquired pneumonia patients

J Infect. 2012 Mar;64(3):268-75. doi: 10.1016/j.jinf.2011.12.007. Epub 2011 Dec 29.


Object: Although emergency department (ED) crowding has been shown to be associated with delayed antibiotics treatment in community-acquired pneumonia (CAP) patients, association between ED crowding with mortality has not been investigated. We hypothesized emergency department crowding is associated with 28-day mortality in CAP patients.

Methods: A retrospective observational study using prospective database was performed on CAP patients who visited a single, urban, tertiary care hospital ED between April 1, 2008 and September 30, 2009. Main outcomes were 28-day mortality and timeliness of antibiotic therapy (within 2, 4, 6, and 8 h of arrival). ED crowding was measured by Emergency Department Occupancy (EDO) rate. A multivariate logistic regression was performed to determine the association of 28-day mortality with EDO rate after adjusting for factors such as time-to-first-antibiotic-dose (TFAD), pneumonia severity index and laboratory markers.

Results: 477 cases were enrolled during the study period. 28-day mortality rate was 4.8%. EDO rate ranged from 37.2% to 162.8%, and median was 97.7% (IQR: 80.2%-116.3%). When categorized into tertiles by EDO rate, high crowding condition (EDO rate >109.3%) was significantly associated with a higher 28-day mortality (adjusted OR = 9.48, 95% CI 1.53-58.90). However, TFAD was not associated with 28-day mortality. ED crowding was not associated with delay of TFAD at various time intervals (2, 4, 6, and 8 h).

Conclusions: ED crowding measured by EDO rate was associated with higher 28-day mortality in CAP patients after adjusting TFAD, pneumonia severity index (PSI), and laboratory markers, although there was no association between ED crowding and TFAD.

MeSH terms

  • Aged
  • Bed Occupancy*
  • Community-Acquired Infections / drug therapy
  • Community-Acquired Infections / mortality*
  • Crowding*
  • Emergency Service, Hospital*
  • Female
  • Hospital Mortality
  • Humans
  • Male
  • Middle Aged
  • Pneumonia / drug therapy
  • Pneumonia / mortality*
  • Retrospective Studies
  • Survival Analysis
  • Time Factors