Clinical utility of biomarkers as predictors of lung function in chronic obstructive pulmonary disease

Background: Recent studies show that chronic obstructive pulmonary disease (COPD) patients exhibit low-grade systemic inflammation, and that plasma endothelin-1(ET-1) and some serum inflammatory markers as hs- CRP, IL-6 and TNF-α are related to faster declines in lung function. We examined correlations between these biomarkers and the decline of lung function in COPD patients. Methods: This study included 96 patients with COPD, besides 20 healthy controls having normal pulmonary lung function. The patients were divided into 4 stages according to lung function measured by spirometer (FEV1 % predicted). All patients were subjected to determination of FEV1 and determination of plasma ET-1, serum hs-CRP, IL-6 and TNF-α. Results: The concentrations of circulating ET-1, hs-CRP, IL-6 and TNF-α, were significantly higher in patients with COPD in comparison to the control group and their levels increased according to the stage of disease. There was a negative correlation between the blood levels of ET-1 with FEV1 in the different stages of COPD. As regards hs-CRP and IL-6 there were significant negative correlation between their levels and FEV1 in stages II and III of COPD but there was no significant correlation between TNF-α and FEV1 in the different stages of COPD. Conclusion: These results suggest that these circulating biomarkers are good candidates as predictors for rapid decline of FEV1 in COPD, although a larger size study with longer term observation is needed to confirm these findings. It is likely that in the future biomarkers will become increasingly required to aid in determining those patients who will benefit from a given drug therapy to improve risk and/or cost benefit, especially since it is becoming more widely considered in COPD. (New York Science Journal 2010;6(3):25-32). (ISSN: 1554-0200).