Circulating fibronectin to C-reactive protein ratio and mortality: a biomarker in COPD?

TitleCirculating fibronectin to C-reactive protein ratio and mortality: a biomarker in COPD?
Publication TypeJournal Article
Year of Publication2008
AuthorsMan, SFP, Xing, L, Connett, JE, Anthonisen, NR, Wise, RA, Tashkin, DP, Zhang, X, Vessey, R, Walker, TG, Celli, BR, Sin, DD
JournalEur Respir J
Volume32
Issue6
Pagination1451-7
Date Published2008 Dec
ISSN1399-3003
KeywordsAdult, Biological Markers, C-Reactive Protein, Female, Fibronectins, Follow-Up Studies, Humans, Inflammation, Male, Middle Aged, Proportional Hazards Models, Pulmonary Disease, Chronic Obstructive, Reproducibility of Results, Treatment Outcome
Abstract

The balance between inflammatory and repair processes is important in maintaining lung homeostasis in chronic obstructive pulmonary disease (COPD). The aim of the present study was to determine whether or not an integrated index of a biomarker involved in inflammation, C-reactive protein (CRP), and another involved in wound repair, fibronectin, may be a good measure to predict clinical outcomes in COPD. Circulating blood levels of CRP and fibronectin were measured in 4,787 individuals with mild-to-moderate COPD who were prospectively followed for >7 yrs after blood collection as part of the Lung Health Study. To assess the balance between repair and inflammation, a simple ratio was calculated by dividing fibronectin levels by CRP levels and a Cox proportional hazards model was used to determine the relationship between this ratio and all-cause and disease-specific causes of mortality. The relationship between the fibronectin to CRP ratio and all-cause mortality was L-shaped. There was an exponential decay in the adjusted hazard function (i.e. the risk of mortality) as the ratio decreased until a value of 148 was reached, beyond which point the hazard function did not change significantly. Similar results were observed for the risk of coronary and cardiovascular mortality. Circulating fibronectin to CRP ratio is significantly associated with all-cause mortality of COPD patients. However, in contrast to other biomarkers, the relationship appears to be L-shaped (and not linear), suggesting a threshold at approximately 150. While promising, future studies are needed to validate this simple index as a biomarker in COPD.

DOI10.1183/09031936.00153207
Alternate JournalEur. Respir. J.
PubMed ID18799503
Grant ListN01-HR-46002 / HR / NHLBI NIH HHS / United States
U10 HL059293 / HL / NHLBI NIH HHS / United States