Exhaled NO Based Treatment of Chronic Obstructive Pulmonary Disease (COPD), ICS/LABA Versus LAMA

It is recognized that eosinophilic airway inflammation is more likely respond to steroid treatment. However, in real-world practice, it is difficult to routinely assess airway inflammation using sputum induction because of technical and facility requirement. COPD (chronic obstructive pulmonary disease) is a heterogeneous disease and it remains a great challenge to identify patients who have eosinophilic airway inflammation and respond to steroid treatment well. A recent study demonstrated elevated plasma D-dimer was associated with acute inflammation and a significant predictor of pulmonary embolism in COPD exacerbated patients. D-dimer may potentially act as a marker of inflammation and a predictor of cardiovascular event in COPD patients. The investigators preliminary study demonstrated that exhaled nitric oxide (eNO) > 23.5 ppb is a good surrogate marker to predict eosinophilic airway inflammation in COPD patients who were newly diagnosed or untreated for at least 3 months. There were significant correlations among sputum eosinophils, eNO and serum total immunoglobulin E (IgE). Particularly, eNO predicted sputum eosinophilia (> 3%) in COPD at a sensitivity and specificity of 62% and 71% respectively. Herein, the investigators test the hypothesis that eNO may act as a biomarker to determine treatment option for COPD.