Improvement of airflow limitation by fluticasone propionate/salmeterol in chronic obstructive pulmonary disease: what is the specific marker?

Backgrounds: Inhaled corticosteroids (ICS)/inhaled long-acting beta2-agonists (LABA) combination drugs are widely used for the long-term management of chronic obstructive pulmonary disease (CORD). However, CORD is a heterogeneous condition and treatment with ICS is associated with a higher risk of pneumonia. The identification of a specific marker for predicting the efficacy of ICS/LABA on pulmonary function would be useful in the treatment of CORD. Methods: Fourteen CORD patients receiving tiotropium therapy participated consecutively. The relationship between the baseline exhaled nitric oxide (FENO) levels as well as serum markers and changes in pulmonary function by fluticasone propionate (FP)/salmeterol (SAL) were analyzed. Results: FP/SAL therapy significantly improved forced vital capacity, forced expiratory volume in 1 s (FEV1), and the third phase slope of the single nitrogen washout curve (Delta N-2) as well as the FEN level. The baseline FEN levels and positive specific IgE (atopy+) were significantly associated with airway obstructive changes assessed by FEV1 and Delta N-2. A baseline FEN level >35 ppb yielded 80.0% sensitivity and 66.7% specificity for identifying the subjects with significant improvement in FEV1 (greater than 200 mL). An atopy+ yielded 60.0% sensitivity and 88.9% specificity for an improvement in FEV1. When combined with FEN > 35 ppb and atopy+, it showed 40% sensitivity and 100.0% specificity for FEV1 improvement. Alternatively, CORD subjects with FENO <= 35 ppb and atopy- did not show significant improvement in FEV1. Conclusion: Combining FEN and specific IgE may be a useful marker for predicting the response to ICS/LABA on airflow limitation in CORD.