Midregional proadrenomedullin as a prognostic tool in community-acquired pneumonia

Chest. 2009 Sep;136(3):823-831. doi: 10.1378/chest.08-1981. Epub 2009 Apr 10.


Background: Midregional proadrenomedullin (MR-proADM) is a potential prognostic biomarker in patients with community-acquired pneumonia (CAP). Previous work has been hampered by sample size and illness spectrum limits. We sought to describe the pattern of MR-proADM in a broad CAP cohort, confirm its prognostic role, and compare its performance to procalcitonin, a novel biomarker of infection.

Methods: We conducted a multicenter prospective cohort study in 28 community and teaching EDs. Patients with a clinical and radiographic diagnosis of CAP were enrolled. We stratified MR-proADM levels a priori into quartiles and quantified severity of illness using the pneumonia severity index (PSI); and confusion (abbreviated mental test score of <or= 8), urea >or= 7 mmol/L, respiratory rate >or= 30 breaths/min, BP < 90 mm Hg systolic or < 60 mm Hg diastolic, age >or= 65 years (CURB-65). The primary outcome was 30-day mortality.

Results: A total of 1,653 patients formed the study cohort. MR-proADM levels consistently rose with PSI class and 30-day mortality (p < 0.001). MR-proADM had a higher area under the curve for 30-day mortality than procalcitonin (0.76 vs 0.65, respectively; p < 0.001), but adding MR-proADM to the PSI in all subjects minimally improved performance. Among low-risk subjects (PSI classes I to III), mortality was low and did not differ by MR-proADM quartile. However, among high-risk subjects (PSI class IV/V; n = 546), subjects in the highest MR-proADM quartile (n = 232; 42%) had higher 30-day mortality than those in MR-proADM quartiles 1 to 3 (23% vs 9%, respectively; p < 0.0001). Similar results were seen with CURB-65. MR-proADM and procalcitonin levels were generally concordant; only 6% of PSI class IV/V subjects in the highest MR-proADM quartile had very low procalcitonin levels (< 0.1 ng/mL).

Conclusions: In our multicenter CAP cohort, MR-proADM levels correlate with increasing severity of illness and death. High MR-proADM levels offer additional risk stratification in high-risk CAP patients, but otherwise MR-proADM levels do not alter PSI-based risk assessment in most CAP patients.

Publication types

  • Multicenter Study
  • Research Support, N.I.H., Extramural

MeSH terms

  • Adrenomedullin / blood*
  • Aged
  • Biomarkers / blood
  • Calcitonin / blood
  • Calcitonin Gene-Related Peptide
  • Community-Acquired Infections / blood*
  • Community-Acquired Infections / mortality
  • Female
  • Humans
  • Male
  • Pneumonia / blood*
  • Pneumonia / mortality
  • Prognosis
  • Prospective Studies
  • Protein Precursors / blood*
  • ROC Curve
  • Severity of Illness Index
  • Statistics, Nonparametric
  • United States / epidemiology


  • Biomarkers
  • CALCA protein, human
  • Protein Precursors
  • proadrenomedullin
  • Adrenomedullin
  • Calcitonin
  • Calcitonin Gene-Related Peptide