ARDS of early or late onset: does it make a difference?

Chest. 2010 Jan;137(1):81-7. doi: 10.1378/chest.09-0714. Epub 2009 Oct 9.


Background: Differences in outcomes have been demonstrated for critically ill patients with late-onset compared with early-onset renal failure and late-onset compared with early-onset shock, which could cause a lead-time bias in clinical trials assessing potential therapies for these conditions. We used data from a large, multicenter observational study to assess whether late-onset ARDS was similarly associated with worse outcomes compared with early-onset ARDS.

Methods: Data were extracted from the Sepsis Occurrence in Acutely Ill Patients (SOAP) study, which involved 198 ICUs from 24 European countries. All adult patients admitted to a participating ICU between May 1, 2002 and May 15, 2002, were eligible, except those admitted for uncomplicated postoperative surveillance. Early/late onset acute lung injury (ALI)/ARDS was defined as ALI/ARDS occurring within/after 48 h of ICU admission.

Results: Of the 3,147 patients included in the SOAP study, 393 (12.5%) had a diagnosis of ALI/ARDS; 254 had early-onset ALI/ARDS (64.6%), and 139 (35.5%) late-onset. Patients with early-onset ALI/ARDS had higher Simplified Acute Physiology II scores on admission and higher initial Sequential Organ Failure Assessment scores. Patients with late-onset ALI/ARDS had longer ICU and hospital lengths of stay than patients with early-onset ALI/ARDS. ICU and hospital mortality rates were, if anything, lower in late-onset ALI/ARDS than in early-onset ALI/ARDS, but these differences were not statistically significant.

Conclusions: There were no significant differences in mortality rates between early- and late-onset ARDS, but patients with late-onset ALI/ARDS had longer ICU and hospital lengths of stay.

Publication types

  • Comparative Study
  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Age of Onset
  • Aged
  • Europe / epidemiology
  • Female
  • Follow-Up Studies
  • Hospital Mortality / trends
  • Humans
  • Incidence
  • Intensive Care Units / statistics & numerical data
  • Length of Stay / trends
  • Male
  • Middle Aged
  • Prognosis
  • Prospective Studies
  • Respiratory Distress Syndrome / epidemiology*
  • Survival Rate / trends