Coal workers' pneumoconiosis: geographic clustering of rapidly progressive disease in the U.S.
Antão-VC; Petsonk-EL; Pinheiro-GA; Attfield-MD
Proc Am Thorac Soc 2005 May; 2(Abstracts):A816
The overall prevalence of coal workers' pneumoconiosis (CWP) has been declining over the last 30 years; nevertheless, short tenure workers continue to develop severe forms of the disease, including progressive massive fibrosis (PMF). Using consensus International Labor Office classifications of films from the NIOSH Coal Workers' X-ray surveillance program, we sought to identify and investigate rapidly progressive cases of CWP. Rapid progression was defined as the development or progression of PMF, and/or an increase in small opacity profusion greater than one minor category over five years, after 1985 (allowing >10 years latency following reduction in the permissible dust exposure level in 1973). County-based statistics were derived by dividing the number of rapidly progressive cases by the number of miners evaluated. Of 29,521 coal miners examined between 1996 and 2002, 886 had radiographic changes consistent with CWP, and 783 miners also had a previous film permitting assessment of progression (total 2214 earlier films). A total of 277 (35.4%) miners showed rapid progression on sequential radiographs. PMF was seen on 41 (14.8%) of those cases. Miners with rapidly progressive CWP were younger (mean age +/- SD = 48 +/- 6 vs 51 +/- 6 years; p<0.01) and reported greater mean tenure in jobs at the coal face (19 +/- 10 vs 17 +/- years; p<0.01), than the other miners with CWP. Rapidly progressive cases were more likely to have worked in small mines (<50 employees) than in larger mines (OR=1.55 [95% CI=1.2-2.0]; p>0.01). A higher proportion of rapidly progressive cases appeared to cluster in eastern Kentucky and western Virginia counties. Despite regulations directed at controlling coal mine dust levels, severe CWP continues to occur. Surveillance for rapid progression of CWP may enhance prevention efforts by identifying specific locations for intervention.
Pneumoconiosis; Coal-mining; Coal-miners; Coal-workers; Coal-workers-pneumoconiosis; Diseases; Occupational-diseases; Fibrosis; X-ray-analysis; Miners; Mining-industry; Dusts; Dust-exposure; Occupational-exposure; Underground-miners; Underground-mining; Demographic-characteristics; Age-factors; Occupational-health; Occupational-hazards; Surveillance
Abstract; Conference/Symposia Proceedings
Issue of Publication
Proceedings of the American Thoracic Society