CT Findings in People Who Were Environmentally Exposed to Asbestos in Korea

Our plain-English summary of CT Findings in People Who Were Environmentally Exposed to Asbestos in Korea, by E.K. Lee, J.S. Kim, Y. Kim, et al (Journal of Korean Medical Science, 2015).

The study

• Authors: E.K. Lee, J.S. Kim, Y. Kim, J.S. Park
• Journal: Journal of Korean Medical Science
• Published: 2015;30(12):1896-901
• Cited by: 4 articles, as counted by NIH iCite
• Read it: PubMed · Publisher · Free full text

Abstract

Asbestos related pleuropulmonary disease has been emerging health problem for recent years. It can cause variable clinical symptoms and radiological abnormalities. However, there has been no report for their characteristics in subjects who were environmentally exposed to asbestos. We reviewed the CT images of 35 people who were environmentally exposed to asbestos in Chungnam province, Korea. The study result showed high incidence of pleural plaque and pulmonary fibrosis on chest CT (94% and 77%, respectively). The common CT findings of lung parenchymal lesions were as follows: centrilobular opacities (94%), subpleural dot-like or branching opacities (80%), interlobular septal thickening (57%), intralobular interstitial thickening (46%), parenchymal bands (43%) and subpleural curvilinear line (29%). There were no significant differences in the prevalence of pulmonary fibrosis and pleural plaques according to sex, age and duration of exposure. In conclusion, pleural plaque and pulmonary fibrosis are common asbestos-related CT finding in the exposed people. Asbestos related lung parenchymal CT findings in the participants with environmental exposure show similar to those observed in the occupational exposure.

In plain English

The authors reviewed chest CT scans of 35 people from villages within 2 km of historic asbestos mines in Chungnam province, Korea. These people had no history of working in asbestos mining. They came from a 2008 to 2009 government health survey of local residents. Pleural plaques were seen in 94.3% (33 of 35) and lung fibrosis in 77.1% (27 of 35). Rates of plaque and fibrosis did not differ significantly by sex, age or length of exposure. Fibrosis was seen in 93.3% of smokers and 65% of nonsmokers, a difference that was not statistically significant (P = 0.052). The most common lung finding was centrilobular opacities (94.3%), which the authors presumed were related to nonspecific dust exposure. The next most common was subpleural dot-like or branching opacities (80%). One person had a pleural mass suspicious of mesothelioma, but this was not confirmed by pathology. The authors concluded that these lung CT findings were similar to those seen with occupational exposure. They noted possible selection bias, no tissue confirmation or lung function testing, and a small number of participants.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Retrospective review of chest CT images from residents screened in a government health impact assessment (a cross-sectional imaging study)
• Who was studied: 35 residents with no occupational history in asbestos mining (17 men, 18 women; mean age 68.5 years; range 48 to 82). They came from 5 villages in Chungnam province, Korea, and were screened from August 2008 to February 2009. Of 215 residents who had chest radiographs, CT was recommended to those with an abnormal radiograph and/or symptoms. 95 had CT and 10 were excluded. Of the remaining 85, 50 had asbestos mining work history and were not included.
• Exposure: Environmental (residential) exposure. Participants were over 40, had lived within 2 km of three historic asbestos mines (Kwangcheon, Joongang and Daeboseoksan), and had at least 1 year of residence during the mining operation period. The introduction, citing earlier work, describes the area's mines as containing mainly chrysotile, tremolite and actinolite. Exposure duration in the group ranged from the 10-19 year category to the 60-69 year category.
• Main results:
  • Pleural plaque was found on CT in 94.3% (33/35) of participants.
  • Lung fibrosis was found on CT in 77.1% (27/35) of participants.
  • There were no significant differences in the prevalence of lung fibrosis or pleural plaque by sex, age or duration of exposure.
  • Lung fibrosis was seen in 93.3% of smokers (14 of 15) and 65% of nonsmokers (13 of 20), P = 0.052. The authors state this was not statistically significant.
  • The most common lung parenchymal finding was centrilobular opacities, in 94.3% of participants. The authors presumed these were related to nonspecific dust exposure.
  • Other lung findings were subpleural dot-like or branching opacities (80%), interlobular septal thickening (57.1%), intralobular interstitial thickening (45.7%), parenchymal bands (42.9%), subpleural curvilinear line (28.6%) and emphysema (17.1%).
  • Parenchymal bands and traction bronchiectasis were more common in older participants (P values 0.021 and 0.033).
  • One participant had a pleural mass suspicious of mesothelioma. It was not pathologically confirmed because the patient refused.
• The authors' conclusion: The authors concluded that pleural plaque and pulmonary fibrosis were frequent in these environmentally exposed people. They also concluded that the asbestos-related lung CT findings were similar to those observed with occupational exposure.
• Limitations the authors state:
  • Not all village residents were scanned. Participants with relatively long and heavy exposure were included, which could lead to selection bias.
  • Neither histologic confirmation nor lung function assessment was done.
  • People who lived with asbestos workers (household exposure) could not be excluded because of lack of history.
  • Smoking was recorded only as a simple yes or no. Pack-years and the timing of smoking were not assessed.
  • Only a small number of participants were included.

Topics

The National Library of Medicine indexes this study under subjects our site covers: Asbestosis.

Medical terms in this study, explained in our Lexicon: Pleural Plaques, Pulmonary Fibrosis, Interstitial, Subpleural Curvilinear Line, Environmental Exposure, Occupational Exposure.

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