Procalcitonin increase in early identification of critically ill patients at high risk of mortality

Crit Care Med. 2006 Oct;34(10):2596-602. doi: 10.1097/01.CCM.0000239116.01855.61.


Objective: To investigate day-by-day changes in procalcitonin and maximum obtained levels as predictors of mortality in critically ill patients.

Design: Prospective observational cohort study.

Setting: : Multidisciplinary intensive care unit at Rigshospitalet, Copenhagen University Hospital, a tertiary reference hospital in Denmark.

Patients: Four hundred seventy-two patients with diverse comorbidity and age admitted to this intensive care unit.

Interventions: Equal in all patient groups: antimicrobial treatment adjusted according to the procalcitonin level.

Measurements and main results: Daily procalcitonin measurements were carried out during the study period as well as measurements of white blood cell count and C-reactive protein and registration of comorbidity. The primary end point was all-cause mortality in a 90-day follow-up period. Secondary end points were mortality during the stay in the intensive care unit and in a 30-day follow-up period. A total of 3,642 procalcitonin measurements were evaluated in 472 critically ill patients. We found that a high maximum procalcitonin level and a procalcitonin increase for 1 day were independent predictors of 90-day all-cause mortality in the multivariate Cox regression analysis model. C-reactive protein and leukocyte increases did not show these qualities. The adjusted hazard ratio for procalcitonin increase for 1 day was 1.8 (95% confidence interval 1.3-2.7). The relative risk for mortality in the intensive care unit for patients with an increasing procalcitonin was as follows: after 1 day increase, 1.8 (95% confidence interval 1.4-2.4); after 2 days increase, 2.2 (95% confidence interval 1.6-3.0); and after 3 days increase: 2.8 (95% confidence interval 2.0-3.8).

Conclusions: A high maximum procalcitonin level and a procalcitonin increase for 1 day are early independent predictors of all-cause mortality in a 90-day follow-up period after intensive care unit admission. Mortality risk increases for every day that procalcitonin increases. Levels or increases of C-reactive protein and white blood cell count do not seem to predict mortality.

Publication types

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

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Biomarkers / metabolism
  • C-Reactive Protein / metabolism
  • Calcitonin / blood*
  • Calcitonin Gene-Related Peptide
  • Child
  • Child, Preschool
  • Critical Illness* / mortality
  • Denmark / epidemiology
  • Female
  • Humans
  • Infant
  • Leukocyte Count
  • Male
  • Middle Aged
  • Multiple Organ Failure / mortality
  • Multiple Organ Failure / prevention & control*
  • Multivariate Analysis
  • Prognosis
  • Proportional Hazards Models
  • Prospective Studies
  • Protein Precursors / blood*
  • Sensitivity and Specificity
  • Sepsis / mortality
  • Sepsis / prevention & control*
  • Survival Analysis


  • Biomarkers
  • CALCA protein, human
  • Protein Precursors
  • Calcitonin
  • C-Reactive Protein
  • Calcitonin Gene-Related Peptide