Clinically Significant Lung Function Abnormalities Among US Former Coal Miners with and Without Radiographic Coal Workers' Pneumoconiosis

ObjectivesThe natural history of coal workers’ pneumoconiosis (CWP) after cessation of exposure remains poorly understood.MethodsWe characterised the development of and progression to radiographic progressive massive fibrosis (PMF) among former US coal miners who applied for US federal benefits at least two times between 1 January 2000 and 31 December 2013. International Labour Office classifications of chest radiographs (CXRs) were used to determine initial and subsequent disease severity. Multivariable logistic regression models were used to identify major predictors of disease progression.ResultsA total of 3351 former miners applying for benefits without evidence of PMF at the time of their initial evaluation had subsequent CXRs. On average, these miners were 59.7 years of age and had 22 years of coal mine employment. At the time of their first CXR, 46.7% of miners had evidence of simple CWP. At the time of their last CXR, 111 miners (3.3%) had radiographic evidence of PMF. Nearly half of all miners who progressed to PMF did so in 5 years or less. Main predictors of progression included younger age and severity of simple CWP at the time of initial CXR.ConclusionsThis study provides further evidence that radiographic CWP may develop and/or progress absent further exposure, even among miners with no evidence of radiographic pneumoconiosis after leaving the industry. Former miners should undergo regular medical surveillance because of the risk for disease progression.

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Continued increase in prevalence of r-type opacities among underground coal miners in the USA

Occupational and Environmental Medicine ◽

10.1136/oemed-2019-105691 ◽

2019 ◽

Vol 76 (7) ◽

pp. 479-481 ◽

Cited By ~ 12

Author(s):

Noemi B Hall ◽

David J Blackley ◽

Cara N Halldin ◽

A Scott Laney

Keyword(s):

Crystalline Silica ◽

Surveillance Program ◽

Lung Pathology ◽

Coal Miners ◽

Binomial Regression ◽

Central Appalachia ◽

The Usa ◽

Coal Workers Pneumoconiosis ◽

Coal Workers ◽

Prevalence Ratios

IntroductionRespirable crystalline silica exposure has been implicated in the resurgence of coal workers’ pneumoconiosis (CWP) in the USA. A 2010 report found an increasing prevalence of r-type opacities, which are associated with silicosis lung pathology, on the radiographs of working underground coal miners in central Appalachia. This analysis updates that report by assessing the prevalence of r-type opacities during 2010–2018 compared with earlier decades.MethodsData from the Coal Workers’ Health Surveillance Program were used to calculate the prevalence of r-type opacities on radiographs of working underground coal miners. The data were restricted to radiographs taken during 1 January 1980 to 15 September 2018. The presence of r-type opacities was defined as an r-type classification for either the primary or secondary shape/size of small opacities. Prevalence ratios for r-type opacities were calculated using log binomial regression.ResultsRadiograph classifications for 106 506 miners were included in analysis. For the USA overall, the prevalence of r-type opacities among miners with radiographs taken during 2010–2018 compared with 1980–1989 has increased (PR 2.4; 95% CI 1.9 to 3.0). For central Appalachia, the proportion of r-type opacities observed increased when comparing 1980–1989 to 2010–2018 (PR 6.0; 95% CI 4.6 to 7.9).ConclusionsThe prevalence of r-type opacities on the radiographs of Appalachian underground coal miners continues to increase, implicating exposure to crystalline silica in respirable coal mine dust. The current findings underscore the importance of monitoring and controlling exposure to silica in coal mines.

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The Risk of Developing Coal Workers' Pneumoconiosis in a German Inception Cohort of Coal Miners of Ruhr Area - Results after 30 Years of Follow-up

Annals of Lung Cancer ◽

10.36959/571/719 ◽

2018 ◽

Vol 2 (1) ◽

Author(s):

Yong M ◽

Anderle L ◽

Lenaerts H ◽

Derwall R ◽

Brand D ◽

...

Keyword(s):

Inception Cohort ◽

Coal Miners ◽

Ruhr Area ◽

Coal Workers Pneumoconiosis ◽

Coal Workers

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Prevalence of spirometry-defined airflow obstruction in never-smoking working US coal miners by pneumoconiosis status

Occupational and Environmental Medicine ◽

10.1136/oemed-2019-106213 ◽

2020 ◽

Vol 77 (4) ◽

pp. 265-267

Author(s):

Laura Kurth ◽

Anthony S Laney ◽

David J Blackley ◽

Cara N Halldin

Keyword(s):

Occupational Safety ◽

Smoking Status ◽

Airflow Obstruction ◽

Forced Expiratory Volume ◽

Severe Form ◽

Surveillance Program ◽

Coal Miners ◽

Coal Workers Pneumoconiosis ◽

Office System ◽

Coal Workers

IntroductionThis study estimated the prevalence of spirometry-defined airflow obstruction and coal workers’ pneumoconiosis (CWP) among never-smoking coal miners participating in the National Institute for Occupational Safety and Health (NIOSH) Coal Workers’ Health Surveillance Program (CWHSP).MethodsData were from working miners screened by a CWHSP mobile unit who had valid spirometry and chest radiography results. Spirometry-defined airflow obstruction was determined when the ratio of forced expiratory volume in the first second to forced vital capacity is less than the lower limit of normal. Chest radiographs were classified according to the International Labour Office system to identify pneumoconiosis, including the most severe form of pneumoconiosis, progressive massive fibrosis (PMF).ResultsPrevalence of airflow obstruction among never-smoking coal miners in this sample was 7.7% overall, 16.4% among miners with CWP and 32.3% among miners with PMF. Airflow obstruction was significantly associated with CWP and PMF.ConclusionsThere was a higher prevalence of airflow obstruction among never-smoking coal miners with pneumoconiosis compared with those without pneumoconiosis. These findings support prior research on airflow obstruction and smoking and show pneumoconiosis might present with an obstructive pattern regardless of smoking status.

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The presence of promatrix metalloproteinase-3 and its relation with different categories of coal workers' pneumoconiosis

Mediators of Inflammation ◽

10.1080/09629350410001688549 ◽

2004 ◽

Vol 13 (2) ◽

pp. 105-109 ◽

Cited By ~ 3

Author(s):

Remzi Altin ◽

Levent Kart ◽

İshak Tekin ◽

Ferah Armutcu ◽

Meltem Tor ◽

...

Keyword(s):

Exposure Duration ◽

Essential Role ◽

Pulmonary Function Tests ◽

Systemic Infection ◽

Enzyme Linked Immunosorbent Assay ◽

Coal Miners ◽

Inactive Form ◽

Significant Difference ◽

Coal Workers Pneumoconiosis ◽

Coal Workers

Extracellular matrix formation (ECM) and remodeling are critical events related to the pathogenesis of pulmonary fibrosis. Matrix metalloproteinases play an essential role in degrading and remodeling the ECM. In this study, we tried to show the presence and correlation of promatrix metalloproteinase-3 (proMMP-3) (the inactive form of metalloproteinase-3) levels in coal workers' pneumoconiosis (CWP) with different categories.The study population consisted of 44 coal miners with CWP (pos CWP). Coal miners without CWP (neg CWP,n=24) and non-underground personnel (controls,n=17) were taken as controls. All coal miners were stable and had no systemic infection or disease. Standard posterio-anterior chest radiographs and pulmonary function tests were performed to exclude any diseases other than CWP. Serum proMMP-3 was analysed using the sandwich enzyme-linked immunosorbent assay according to the manufacturer's instructions (The Binding Site, Birmingham, UK).Mean proMMP-3 values of the all three groups were compared and a significant statistical difference obtained (p<0.001). In addition, a statistically significant difference was found between categories of the disease and proMMP-3 values (p<0.05). The effects of age, exposure duration and cigarette smoking on proMMP-3 values in coal miners with CWP were investigated. There were no correlations between age, smoking and proMMP-3 values. However, a positive correlation was found between exposure duration and proMMP-3 values (r=0.447,p=0.008).In conclusion, proMMP-3 (prostromelysin 1) may play an essential role in degrading and remodeling the ECM in workers with pneumoconiosis. ProMMP-3 may also reflect the stage of pneumoconiosis disease.

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