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.