Anti-Inflammatory Effects of Chinese Herbal Medicine on COPD: A Systematic Review

Background: Airway inflammation and inflammatory mediators play an imperative role in the pathogenesis of COPD.Currently, understanding of the anti-inflammatory effect of Chinese herbal medicine (CHM) on COPD is limited, and CHM's mechanism of actions is unclear.This systematic review (SR) evaluates anti-inflammatory effects of CHM on the concentration of various inflammatory mediators, such as Tumor Necrosis Factor-alpha (TNF-α) and interleukin-8 (IL-8), in the sputum and serum of COPD patients. Methods:The studies chosen for this SR were obtained from Chinese and English databases.The study selection criteria were based on randomized, controlled trials of stable COPD patients on adjunct oral CHM; and the changes in concentration of inflammatory mediators post-treatment were analyzed via meta-analysis.Results: 2,268 patients in 29 studies were evaluated.2 studies were assessed to be of low-risk in all domains.The results showed significant reduction in the serum level of IL-8 (mean: -1.27 and 95% confidence interval (CI) [-1.86, -0.68]) and TNF-α (Mean: -0.72 and 95% CI [-1.01, -0.43]) in patients treated with CHM plus bronchodilators, compared to bronchodilators alone.Conclusion: This SR explains CHM's mechanism of action, and demonstrates CHM's anti-inflammatory effects on patients with stable COPD.