Plasma C-reactive protein levels are associated with improved outcome in ARDS.
BACKGROUND
C-reactive protein (CRP) has been studied as a marker of systemic inflammation and outcome in a number of diseases, but little is known about its characteristics in ARDS. We sought to examine plasma levels of CRP in patients with ARDS and their relationship to outcome and measures of illness severity.


METHODS
We measured CRP levels in 177 patients within 48 h of disease onset and tested the association of protein level with 60-day mortality, 28-day daily organ dysfunction scores, and number of ventilator-free days.


RESULTS
We found that CRP levels were significantly lower in nonsurvivors when compared with survivors (p = 0.02). Mortality rate decreased with increasing CRP decile (p = 0.02). An increasing CRP level was associated with a significantly higher probability of survival at 60 days (p = 0.005). This difference persisted after adjustment for age and severity of illness in a multivariable model (p = 0.009). Multivariable models were also used to show that patients in the group with higher CRP levels had significantly lower organ dysfunction scores (p = 0.001) and more ventilator-free days (p = 0.02).


CONCLUSIONS
Increasing plasma levels of CRP within 48 h of ARDS onset are associated with improved survival, lower organ failure scores, and fewer days of mechanical ventilation. These data appear to be contrary to the established view that CRP is solely a marker of systemic inflammation.
Bajwa
Ednan K
EK
Pulmonary and Critical Care Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA.
Khan
Uzma A
UA
Department of Environmental Health, Harvard School of Public Health, Boston, MA.
Januzzi
James L
JL
Cardiology Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA.
Gong
Michelle N
MN
Pulmonary and Critical Care Division, Mount Sinai School of Medicine, New York, NY.
Thompson
B Taylor
BT
Pulmonary and Critical Care Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA.
Christiani
David C
DC
Pulmonary and Critical Care Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA; Department of Environmental Health, Harvard School of Public Health, Boston, MA. Electronic address: dchris@hsph.harvard.edu.
D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000378:metabolism*; D015331:Cohort Studies; D016001:Confidence Intervals; D018572:Disease-Free Survival; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007362:Intensive Care Units; D053208:Kaplan-Meier Estimate; D017114:Liver Failure, Acute / Q000097:blood / Q000175:diagnosis; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011336:Probability; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012128:Respiratory Distress Syndrome / Q000097:blood* / Q000188:drug therapy / Q000401:mortality*; D018570:Risk Assessment; D012720:Severity of Illness Index; D016019:Survival Analysis
D000305:Adrenal Cortex Hormones; D015415:Biomarkers; D002097:C-Reactive Protein