C-reactive protein as a predictor of prognosis in chronic obstructive pulmonary disease.
BACKGROUND
Patients with chronic obstructive pulmonary disease (COPD) have an ongoing systemic inflammation, which can be assessed by measuring serum C-reactive protein (CRP).


OBJECTIVE
To determine whether increased serum CRP in individuals with airway obstruction predicts future hospitalization and death from COPD.


METHODS
We performed a cohort study with a median of 8-yr follow-up of 1,302 individuals with airway obstruction selected from the ongoing Copenhagen City Heart Study.


RESULTS
We measured serum CRP at baseline, and recorded COPD admissions and deaths as outcomes. During follow-up, 185 (14%) individuals were hospitalized due to COPD and 83 (6%) died of COPD. Incidences of COPD hospitalization and COPD death were increased in individuals with baseline CRP > 3 mg/L versus < or = 3 mg/L (log rank: p < 0.001). After adjusting for sex, age, FEV(1)% predicted, tobacco consumption, and ischemic heart disease, the hazard ratios for hospitalization and death due to COPD were increased at 1.4 (95% confidence interval, 1.0-2.0) and 2.2 (1.2-3.9) in individuals with baseline CRP > 3 mg/L versus < or = 3 mg/L. After close matching for FEV(1)% predicted and adjusting for potential confounders, baseline CRP was, on average, increased by 1.2 mg/L (analysis of variance: p = 0.002) and 4.1 mg/L (p = 0.001) in those who were subsequently hospitalized or died of COPD, respectively. The absolute 10-yr risks for COPD hospitalization and death in individuals with CRP above 3 mg/L were 54 and 57%, respectively, among those older than 70 yr with a tobacco consumption above 15 g/d and an FEV(1)% predicted of less than 50.


CONCLUSIONS
CRP is a strong and independent predictor of future COPD outcomes in individuals with airway obstruction.
Dahl
Morten
M
Department of Clinical Biochemistry, Herlev University Hospital, Herlev, Denmark.
Vestbo
Jørgen
J
Lange
Peter
P
Bojesen
Stig E
SE
Tybjaerg-Hansen
Anne
A
Nordestgaard
Børge G
BG
D000368:Aged; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000032:analysis*; D015331:Cohort Studies; D005260:Female; D006760:Hospitalization; D006801:Humans; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011379:Prognosis; D029424:Pulmonary Disease, Chronic Obstructive / Q000097:blood / Q000175:diagnosis* / Q000401:mortality*; D012306:Risk
D015415:Biomarkers; D002097:C-Reactive Protein