Chest
Volume 133, Issue 6, June 2008, Pages 1336-1343
Journal home page for Chest

Original Research
COPD
C-Reactive Protein Levels and Survival in Patients With Moderate to Very Severe COPD

https://doi.org/10.1378/chest.07-2433Get rights and content

Background

Serum levels of C-reactive protein (CRP) are increased in patients with COPD and correlate modestly with variables predictive of outcomes. In epidemiologic studies, CRP level is associated with all-cause mortality in patients with mild-to-moderate disease.

Objective

To determine if CRP levels are associated with survival in patients with moderate to very severe COPD in comparison with other well-known prognostic parameters of the disease.

Methods

In 218 stable patients with COPD, we measured baseline serum CRP level, BODE (body mass index, obstruction, dyspnea, and exercise capacity) index and its components, arterial oxygenation (Pao2), inspiratory capacity (IC) to total lung capacity (TLC) ratio, and Charlson comorbidity score. We followed up the patients over time and evaluated the strength of the association between the variables and all-cause mortality.

Results

During the follow-up time (median, 36 months; 25th to 75th percentiles, 24 to 50 months), 54 patients (25%) died. CRP levels were similar between survivors and the deceased (median, 3.8 mg/L; 95% confidence interval, 1.9 to 8.1; vs median, 4.5 mg/L; 95% confidence interval, 2.1 to 11.5; p=0.22) and was not significantly associated with survival.

Conclusions

In this population of patients with clinically moderate to very severe COPD, the level of CRP level was not associated with survival compared with other prognostic clinical tools such as the BODE index, modified Medical Research Council scale, 6-min walk distance, percentage of predicted FEV1, IC/TLC ratio <0.25, and Pao2. Other long-term studies of well-characterized patients with COPD could help determine the exact role of CRP levels as a biomarker in patients with clinical COPD.

Section snippets

Study Population

This is a prospective observational study of patients from the two sites of the BODE cohort that had measured CRP levels at baseline.6, 7 Patients from the pulmonary clinics at the Hospital Universitario Ntra Sra de Candelaria, in Tenerife, Spain, and from Caritas St Elizabeth's Medical Center in Boston, MA, signed the informed consent approved by the Human Institutional Review Boards. The patients were consecutively included if they had smoked ≥20 pack-years and had a postbronchodilator FEV1

Results

The clinical and physiologic characteristics of all patients are summarized in Table 1. This predominantly male COPD population included patients with Global Initiative for Chronic Obstructive Lung Disease (GOLD)/ATS/European Respiratory Society stages II to IV. Most had a normal BMI, with 32% of them having an IC/TLC ratio <0.25. Half had an MMRC score >2 and some degree of comorbidity. At the end of the follow-up time, 25% (54 patients) had died and 7% (15 patients) were not available for

Discussion

The most important finding of this study is that a baseline serum CRP level was not significantly associated with survival status in patients with clinically stable moderate to very severe COPD. Numerous prospective studies have shown that the serum level of CRP is independently associated with future mortality. Levels of CRP are associated with cardiovascular risk of death in the general population21 as well as in patients with other conditions, such as diabetes22 and renal disease.23 Although

References (29)

  • RA Pauwels et al.

    Burden and clinical features of chronic obstructive pulmonary disease (COPD)

    Lancet

    (2004)
  • DM Mannino et al.

    Obstructive and restrictive lung disease and markers of inflammation: data from the third National Health and Nutrition Examination

    Am J Med

    (2003)
  • M Charlson et al.

    Validation of a combined comorbidity index

    J Clin Epidemiol

    (1994)
  • R Pauwels et al.

    Global strategy for the diagnosis, management and prevention of chronic obstructive pulmonary disease: NHLBI/WHO Global Initiative for Chronic Obstructive Lung Disease (GOLD) workshop summary

    Am J Respir Crit Care Med

    (2001)
  • A Agustí

    Systemic effects of chronic obstructive pulmonary disease

    Proc Am Thorac Soc

    (2005)
  • WQ Gan et al.

    Association between chronic obstructive pulmonary disease and systemic inflammation: a systematic review and meta-analysis

    Thorax

    (2004)
  • MB Pepys et al.

    C-reactive protein: a critical update

    J Clin Invest

    (2003)
  • JP de Torres et al.

    C-reactive protein levels and clinically important predictive outcomes in stable COPD patients

    Eur Respir J

    (2006)
  • VM Pinto-Plata et al.

    C-reactive protein in patients with COPD, control smokers, and nonsmokers

    Thorax

    (2006)
  • JR Hurst et al.

    Use of plasma biomarkers at exacerbation of chronic obstructive pulmonary disease

    Am J Respir Crit Care Med

    (2006)
  • DD Sin et al.

    Effects of fluticasone on systemic markers of inflammation in chronic obstructive pulmonary disease

    Am J Respir Crit Care Med

    (2004)
  • GD Lowe et al.

    C-reactive protein and cardiovascular disease: weighing the evidence

    Curr Atheroscler Rep

    (2006)
  • SFP Man et al.

    C reactive protein and mortality in mild to moderate chronic obstructive pulmonary disease

    Thorax

    (2006)
  • M Dahl et al.

    C-reactive protein as a predictor of prognosis in COPD

    Am J Respir Crit Care Med

    (2007)
  • Cited by (129)

    • Electrochemical methods for detection of biomarkers of Chronic Obstructive Pulmonary Disease in serum and saliva

      2019, Biosensors and Bioelectronics
      Citation Excerpt :

      The normal level of CRP in serum can increase by several orders of magnitude (Pepys and Hirschfield, 2003). It is reported that the level of CRP can help to predict several diseases such as the coronary heart disease (Danesh, 2000), ischemic stroke (Cao et al., 2003), acute myocardial infarction (Suleiman et al., 2006) and COPD (Broekhuizen et al., 2006; de Torres et al., 2008; Dev et al., 1998; Stolz et al., 2007). It is reported that immunonephelometric or immunoturbidimetric assays are used to determine the level of CRP in the lab, which is quite expensive and time-consuming (Şişman et al., 2007).

    • Acute Phase Reactants and the Concept of Inflammation

      2016, Kelley and Firestein's Textbook of Rheumatology: Volumes 1-2, Tenth Edition
    View all citing articles on Scopus

    The author have no conflicts of interest to disclose.

    Funding was provided partially by the Canarian Research and Health Foundation.

    Reproduction of this article is prohibited without written permission from the American College of Chest Physicians (www.chestjournal.org/misc/reprints.html).

    View full text