Albumin and C-reactive protein have prognostic significance in patients with community-acquired pneumonia

J Crit Care. 2011 Jun;26(3):287-94. doi: 10.1016/j.jcrc.2010.10.007. Epub 2010 Dec 3.

Abstract

Purpose: This study aims to determine the association of commonly used biochemical markers, such as albumin and C-reactive protein (CRP), with mortality and the prognostic performance of these markers combined with the pneumonia severity index (PSI) for mortality and adverse outcomes in patients with community-acquired pneumonia (CAP).

Materials and methods: The data were gathered prospectively for patients hospitalized with CAP via the emergency department. Laboratory values, including CRP and albumin, clinical variables, and the PSI were measured. Primary outcomes were 28-day mortality and survival times. Secondary outcome was admission to the intensive care unit, vasopressor use, or the need for mechanical ventilation during the hospital stay.

Results: A total of 424 patients were included. The 28-day mortality was 13.7%. C-reactive protein and albumin were significantly different between survivors and nonsurvivors. In logistic regression analysis, CRP and albumin were independently associated with 28-day mortality (P < .05). Receiver operating characteristic curves showed improved mortality prediction by adding CRP or albumin to the PSI scale. The Cox proportional hazards analysis showed that high serum albumin (≥3.3 mg/dL) had a hazard ratio of 0.5 (95% confidence interval, 0.3-0.9), and high CRP (≥14.3 mg/dL) had a hazard ratio of 2.0 (95% confidence interval, 1.1-3.4). For predicting secondary outcome, adding albumin to PSI increased areas under the curve significantly, but CRP did not.

Conclusion: Albumin and CRP were associated with 28-day mortality in hospitalized patients with CAP, and these markers increased prognostic performance when combined with the PSI scale.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Albumins / analysis*
  • Biomarkers / blood
  • C-Reactive Protein / analysis*
  • Community-Acquired Infections / blood
  • Community-Acquired Infections / mortality
  • Female
  • Hospital Mortality
  • Humans
  • Male
  • Middle Aged
  • Pneumonia* / blood
  • Pneumonia* / mortality
  • Pneumonia* / therapy
  • Predictive Value of Tests
  • Prognosis
  • Prospective Studies
  • Severity of Illness Index*
  • Survival Rate
  • Treatment Outcome

Substances

  • Albumins
  • Biomarkers
  • C-Reactive Protein