The effects of inhaled and oral corticosteroids on serum inflammatory biomarkers in COPD: an exploratory study

Background: Several studies suggest that inhaled and oral corticosteroids repress systemic inflammation in chronic obstructive pulmonary disease (COPD). However, the cytokines that may respond to these medications are unclear. Method: We used data from 41 patients with a history of stable moderate COPD (average age 64 years) who were randomised to inhaled fluticasone (500 μg twice daily from a Diskus inhaler), oral prednisone (30 mg daily) or placebo for 2 weeks. Using a multiplexed array system, different serum cytokines that have been implicated in COPD pathogenesis were measured. Results: We found that compared with placebo, inhaled fluticasone significantly reduced levels of soluble tumour necrosis factor receptor-2 (sTNF-R2) by 24% (95% CI, 7—38%; p = 0.01), monocyte chemoattractant protein-1 by 20% (95% CI, 5—32%; p = 0.01), interferon gamma inducible CXCL10 (IP-10) by 43% (95% CI, 3—66%; p = 0.04), and soluble L-selectin levels by 15% (95% CI, 1—28%; p = 0.04). Compared with placebo, oral prednisone reduced levels of sTNF-R2 by 26% (95% CI, 15—36%; p < 0.001), L-selectin by 22% (95% CI, 8—34%; p = 0.004), intercellular adhesion molecule-1 by 31% (95% CI, 9—48%; p = 0.01), pulmonary and activation-regulated chemokine (PARC) by 18% (95% CI, 2—32%; p = 0.03) and IP-10 by 40% (95% CI, 0—64%; p = 0.05). sTNF-R2, L-selectin and IP-10 were significantly reduced by both oral and inhaled corticosteroids. The other cytokines were not significantly repressed by either oral or inhaled corticosteroids. Conclusions: In summary, inhaled and oral corticosteroids significantly repressed a selected number of systemic cytokines in patients with stable, moderate COPD; most of the steroid-responsive cytokines appear to be chemoattractants.