Inflammatory biomarkers improve the clinical prediction of mortality in COPD

The addition of changes in inflammatory biomarkers to established clinical variables improves the prediction of mortality in patients with chronic obstructive pulmonary disease (COPD), according to a new study.

"COPD is characterized by low-grade inflammation, so we hypothesized that the addition of inflammatory biomarkers to established predictive factors would improve the prediction of mortality," said lead author Bartolome Celli, lecturer in medicine at Harvard Medical School and member of the Pulmonary and Critical Care Division of Brigham and Women's Hospital in Boston. "We found that the addition of a panel of selected biomarkers to clinical variables significantly improved the ability of clinical variables to predict mortality in these patients."

The findings were published online ahead of print publication in the American Thoracic Society's American Journal of Respiratory and .

The researchers analyzed prospectively collected data on 1,843 COPD patients from the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE) study. Of these 1,843 patients, 168 (9.1%) died during the three-year follow-up.

Clinical predictors of morality included age, BODE (Body-Mass Index, , Dyspnea, and Exercise Capacity) index , and incidence of hospitalizations due to exacerbations of COPD in the year prior to the study. A predictive model for mortality using these clinical variables had a C-statistic (which measures the ability of how well a clinical prediction rule can correctly rank-order patients by risk) of 0.686. Adding interleukin-6 (IL-6) to the predictive model significantly improved the C-statistic to 0.708, and the addition of a panel of biomarkers including white blood cell counts, IL-6, C-reactive protein (CRP), interleukin-8 (IL-8), fibrinogen, chemokine (C-C-motif) ligand 18 (CCL-18), and surfactant protein D (SP-D) further improved the C-statistic to 0.726.

"This panel of selected biomarkers was not only elevated in non-survivors in our cohort, but was associated with mortality over three years of follow-up after adjusting for clinical variables known to predict mortality in patients with COPD," said Dr. Celli. "Except for IL-6, these biomarkers improved the predictive value of our model only marginally when considered individually, but they improved the model significantly when analyzed as a group."

The study had several limitations, including the lack of a study adjudication committee to specify causes of death, the exclusion of some biomarkers thought to be important in the pathobiology of COPD, and the lack of a validating cohort.

"Adding white blood cell counts and measurement of changes in systemic levels of IL-6, CRP, IL-8, fibrinogen, CCL-18, and SP-D significantly improves the ability of clinical variables to predict mortality in patients with COPD," said Dr. Celli. "This is the first study to show that the addition of biomarker levels to clinical predictors in COPD adds relevant prognostic information."

add to favorites email to friend print save as pdf

Related Stories

New tool to predict the risk of death in COPD

Aug 28, 2009

Researchers have developed an index scale to help physicians predict a patient's risk of dying from chronic obstructive pulmonary disease (COPD). The ADO index can help physicians assess the severity of a patient's illness ...

Researchers link novel biomarkers to asthma and COPD

Mar 11, 2011

Four novel biomarkers have been identified which may aid in the diagnosis and management of asthma and chronic obstructive pulmonary disease (COPD), according to a study conducted by researchers in Australia, who determined ...

Recommended for you

Mali announces new Ebola case

15 hours ago

Mali announced Saturday a new case of Ebola in a man who is fighting for his life in an intensive care unit in the capital Bamako.

Plague outbreak kills 40 in Madagascar: WHO

15 hours ago

An outbreak of plague has killed 40 people in Madagascar, the World Health Organization said, warning that the disease could spread rapidly in the country's densely populated capital Antananarivo.

UN chief: Ebola cases in Mali a 'deep concern'

Nov 21, 2014

The United Nations chief warned Friday that Ebola may be easing in part of West Africa but is still hitting hard in other areas and outpacing the international response.

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.