Effect of salmeterol/fluticasone propionate on airway inflammation in COPD:a randomized controlled trial

Abstract

Airway inflammation in chronic obstructive pulmonary disease (COPD) is characterized by infiltration of CD8+ T cells and CD68+ macrophages and an increased number of neutrophils, whereas few studies have described the presence of eosinophils. Although anti-inflammatory effects of corticosteroids in stable COPD are unclear, recent studies suggest that combination therapy could be beneficial. We therefore evaluated combined salmeterol/fluticasone propionate (SFC) and fluticasone propionate (FP) alone on inflammatory cells in the airways of COPD patients. Patients were treated in a randomized, double-blind, parallel-group, placebo-controlled trial with either a combination of 50μg salmeterol and 500μg FP twice daily ([SFC] n=19, 19 male, mean age 62), 500μg FP twice daily (n=20, 15 male, mean age 64), or placebo (n=21, 17 male, mean age 66) for 3 months. At the start and end of treatment, bronchoscopy with bronchial biopsies was performed, and numbers of CD8+ T lymphocytes, CD68+ macrophages, neutrophils and eosinophils were measured. CD8+ cells were significantly reduced by SFC compared with placebo (difference -98.05 cells/mm2; 95% CI -143.14 to -52.9; p<0.001). Such a marked effect was not seen with FP alone (-44.67 cells/mm2; 95% CI -90.92 to 1.57; p=0.06). CD68+ macrophages were also reduced by SFC compared with placebo (difference -31.68 cells/mm2; 95% CI -61.07 to -2.29; p=0.03) but not by FP. SFC did not significantly change neutrophils and eosinophils compared with placebo. SFC has airway anti-inflammatory effects not seen with inhaled corticosteroids alone.