Risk Factors of Silicosis Progression: A Retrospective Cohort Study in China

Abstract

BackgroundSilicosis poses a threat to workers’ health due to the irreversible lung lesions.DesignA retrospective cohort study.MethodsA total of 259 patients [80 worked with artificial stone (AS), 179 with non-artificial stone (non-AS)] with confirmed silicosis were included in this study. Forty-one of AS and 91 of non-AS had approximately 2 years’ follow-up records [lung function tests and high-resolution computer tomography (HRCT)]. Compared with the first records, increased, densified, or newly emerging lesions in lung HRCT images were judged as progression of the disease. Cox proportional hazards models were used to determine the risk factors. Kaplan–Meier survival curve and log-rank test were used to compare prognostic factors for cumulative risk of progression.ResultsIn 132 patients with median follow-up of 24.0 months (IQR, 13.8, 24.9), 66 patients showed progression, in them, 36 (87.8%) were from AS group and 30 (32.9%) from non-AS group. Working experience of AS processing (hazard ratio, 5.671; 95% CI, 3.048–10.550) and complicated silicosis in CT images (hazard ratio, 2.373; 95% CI, 1.379–4.082) were the main risk factors associated with progression. Forced vital capacity decreased after 1-year (241.5 vs. 55.2 mL) and 2-year (328.1 vs. 68.8 mL) follow-up in the two groups (AS vs. non-AS). History of anti-tuberculosis medication, chest oppression and pain, ground-glass opacity, pleural abnormalities, and restrictive pulmonary dysfunction were more frequently found on HRCT images in the AS group than non-AS group. Lung functions (DLCO, %) were lower in the current/former smokers than the non-smokers (P < 0.05) in AS patients.ConclusionPrevention and protection rules are needed to be enforced in the occupation involving AS processing; smoking may be associated with declined lung function in AS patients.

Clinical efficacy of tetrandrine in artificial stone-associated silicosis: A retrospective cohort study

“…Since then, outbreaks of silicosis among AS workers have been reported around the world (3)(4)(5). It has been noted that AS-associated silicosis progresses more rapidly and has a worse prognosis than non-AS-associated silicosis due to exposing dust containing crystalline silica over 90% (6)(7)(8). Importantly, there is currently no effective antifibrosis treatment for silicosis.…”

Accelerated silicosis in sandblasters: Pathology, mineralogy, and clinical correlates

“…Most reports of accelerated silicosis use radiographic presence of silicotic nodules as a "threshold" for diagnosis and most reports of pathology also note the presence of silicotic nodules. 7,30,31,36 Our study, it should be noted, includes 25 (of 46 men) in which radiologic nodules were not seen on presentation, and silicotic nodules were only seen in 12 (27%) of biopsy samples. All patients with biopsies were included in this report, which includes two cases where sandblasting exposure was 18 and 25 years duration.…”

Development and Validation of the Tuberculosis Risk Score for Smokers (TBRSS)

“…However, some limitations were also encountered in developing and validating the TBRSS. There are few variables that were reported to be associated with smoking and TB development, such as HIV status [ 40 ], weight maintenance [ 41 ] and occupational hazards (stone processing and silicosis) [ 42 ], which were not included as the study predictors. Response bias may have occurred when the team member interviewed the patients via telephone call or by face-to-face interview.…”