Abstract: Objective To investigate the effects of rock salt aerosol (RSA) on airway inflammation in patients with pneumoconiosis combined with chronic obstructive pulmonary disease (COPD) through modulating Th17/Treg immune balance. Methods A prospective randomized controlled test enrolled 86 patients with pneumoconiosis and COPD, who were randomly assigned to a RSA group or control group. Both groups received standardized basic treatment then the RSA group inhaled RSA and the control group inhaled saline aerosol for 24 weeks. Pulmonary function tests, blood gas analysis, inflammatory markers, Th17/Treg immune balance indicators, and clinical symptoms were recorded to evaluate treatment efficacy. Results A total of 41 patients in the RSA group and 40 in the control group completed the study. The RSA group showed significantly better improvements in pulmonary function parameters, blood gas status, and inflammatory factors (IL-6, IL-8) as compared to the control group (P＜0.05). The RSA group also demonstrated a reduced Th17 cell proportion, increased Treg cell proportion and a more significant decrease in the Th17/Treg ratio (P＜0.001). Clinical symptom scores were lower, with a total effective rate of 90.24% (compared to 52.50% in the control group, P＜0.001). Correlation analysis revealed that the Th17/Treg ratio in the RSA group was positively correlated with inflammatory factors and negatively correlated with pulmonary function. Conclusions RSA effectively improves pulmonary function and clinical symptoms of pneumoconiosis patients complicated with COPD. Its mechanism may involve regulation of Th17/Treg balance and inhibition of airway inflammation.

Key words: rock salt aerosol, pneumoconiosis, chronic obstructive pulmonary disease (COPD), Th17/Treg immune balance, airway inflammation