Progression of Chest X-ray Findings of Silicosis Among Fluorspar Miners and Prognostic Factors Retrospective Cohort Study in Mongolia

Abstract

Objective: This study aimed to delineate the natural progression of silicosis in fluorspar miners after the termination of dust exposure and identify its prognostic factors. Methods: This retrospective cohort study, conducted from 2000 to 2019, included 67 former miners. Radiological images were evaluated by comparing the initial and most recent radiographs using the International Classification of Radiographs of Pneumoconiosis. Cox multivariate proportional hazard models were used to estimate the hazard ratios using follow-up time to analyze the multivariable study of associated prognostic factors. Results: Among the participants, 50 (75%) exhibited progression over 2 to 16 years (median, 5.8 years). The Cox analysis highlighted older age as a likely precursor to the progression of significant opacities. Additionally, higher International Labour Organization category grades at onset were associated with disease progression. Conclusions: Nearly three-quarters of the miners diagnosed with silicosis demonstrated radiological progression even after the termination of dust exposure. Advancement in age and the degree of initial radiological opacity were associated with progression.