Abstract
Fine particulate matter (PM(2.5)) is well known to impair lung function. Strategies protecting against PM(2.5)-exerted lung dysfunction have been less investigated. Qianjinweijing decoction (QJWJ), a decoction of a herbal medicine of natural origin, has been used to treat lung disorders as it inhibits oxidation and inflammation. However, no clinical trial has yet evaluated the role of QJWJ in PM(2.5)-induced lung dysfunction. Therefore, we conducted a randomized, double-blind, placebo-controlled trial to assess whether QJWJ provided lung benefits against the adverse effects of PM(2.5) exposure among adults. Eligible participants (n = 65) were recruited and randomized to receive QJWJ decoction (n = 32) or placebo (n = 33) for 4 weeks. The restrictive ventilatory defect (RVD), lung function parameters, and induced sputum were analyzed. The PM(2.5) exposure concentration was significantly associated with the vital capacity (VC), peak expiratory flow (PEF), and forced expiratory flow at 75% of the forced vital capacity (FEF(75)). The negative associations between PM(2.5) and the lung function parameters were eliminated in response to the QJWJ intervention. Additionally, the percentage of RVD (P = 0.018) and the proportion of eosinophils (Eo%) in induced sputum (P = 0.014) in the QJWJ group was significantly lower than that in the placebo group. This study demonstrated that QJWJ could alleviated PM(2.5)-induced lung dysfunction and could be a potential treatment for air pollution-related chronic respiratory disease.