Pulmonary function, smoking habits, and high resolution computed tomography (HRCT) early abnormalities of lung and pleural fibrosis in shipyard workers exposed to asbestos

Our plain-English summary of Pulmonary function, smoking habits, and high resolution computed tomography (HRCT) early abnormalities of lung and pleural fibrosis in shipyard workers exposed to asbestos, by S. Neri, P. Boraschi, A. Antonelli, et al (American Journal of Industrial Medicine, 1996).

The study

• Authors: S. Neri, P. Boraschi, A. Antonelli, F. Falaschi, L. Baschieri
• Journal: American Journal of Industrial Medicine
• Published: 1996;30(5):588-95
• Cited by: 38 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

To evaluate the presence of asbestos-related pleural and parenchymal abnormalities and their correlation with pulmonary function and smoking habits, 119 asbestos-exposed asymptomatic workers (mean age, 46.2 years; mean duration of asbestos exposure, 8.6 years; mean latency time, 21.6 years) with normal standard P.A chest radiographs were submitted to HRCT, CO-diffusing capacity and pulmonary function tests. HRCT scans were normal only in 31 (26%) examined workers; 31 (26%) subjects showed both pleural and parenchymal involvement, and 50 (42%) and seven (6%) had exclusively pleural and parenchymal abnormalities, respectively. Based on CO-diffusing capacity and pulmonary function tests, no significant difference was demonstrated between workers with pleural lesions and subjects with normal pleura; however, lower values of FVC were observed in the nonsmoking workers with parenchymal abnormalities in comparison with nonsmoking subjects with normal parenchyma (78.2 vs. 89.7% of predicted values; p = 0.03 by student's two-tailed t test), and lower values of FEV1/FVC in the smokers with parenchymal lesions with respect to smokers with normal parenchyma (93.7 vs. 100.2% of predicted values; p = 0.005 by students' two-tailed t test). In conclusion, our results demonstrate that HRCT may detect early parenchymal abnormalities which correlate with exposure to asbestos and respiratory function impairment, including a reduction in obstructive indices in smokers occupationally exposed to asbestos, without any clinically evident disease.

In plain English

This cross-sectional study examined 119 men from an Italian shipyard and naval furniture factory. The factory cut marinite panels containing about 36-44% amosite. All had normal standard chest X-rays and no lung symptoms. From 1991 to 1994 they had high resolution CT and lung function tests. CT was normal in 31; 50 had only pleural plaques, 7 had only lung-tissue (parenchymal) abnormalities, and 31 had both. Workers with parenchymal abnormalities had longer total exposure (10.9 vs 7.5 years) and higher cigarette consumption than those without. None of the 22 workers exposed over 15 years had a normal scan. Pleural plaques were not linked to significant lung function differences. Among nonsmokers, those with parenchymal abnormalities had lower FVC (78.2 vs 89.7% of predicted). Among smokers or ex-smokers, those with parenchymal abnormalities had lower FEV1/FVC (93.7 vs 100.2% of predicted). The authors concluded that CT abnormalities were strictly related to asbestos exposure and may correlate with function impairment. They said the sample was probably too small to show significantly more parenchymal abnormalities in smokers or ex-smokers (28/75) than nonsmokers (10/44).

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: cross-sectional study using high resolution CT (HRCT), lung function tests and CO-diffusing capacity
• Who was studied: 119 men from the same shipyard and naval furniture factory in Italy (75 smokers or ex-smokers, 44 nonsmokers; mean age 46.2 years), examined from January 1991 to December 1994; all had normal standard chest radiographs and no lung symptoms; 42 of 161 blue-collar employees were excluded
• Exposure: Marinite panels containing about 36-44% amosite, cut and fabricated for naval furnishing, ceilings and fireproof bulkheads; air levels measured in 1977 were 6, 18 and 12 fibers per cubic centimetre at three machines; mean total exposure 8.6 years and mean heavy exposure 3.4 years
• Main results:
  • Of 119 workers, 31 had normal HRCT, 50 had only pleural plaques, 7 had only parenchymal abnormalities, and 31 had both
  • Among 39 workers exposed less than 5 years, 19 (49%) had normal CT; none of the 22 workers exposed more than 15 years had normal CT
  • The 38 workers with parenchymal abnormalities had longer total exposure than the 81 with normal parenchyma (10.9 vs 7.5 years, p = 0.003), longer heavy exposure (5.0 vs 2.7 years, p = 0.005) and longer latency (24.5 vs 21.9 years, p = 0.03)
  • Cigarette consumption was higher in workers with parenchymal abnormalities than in those with normal parenchyma (14.0 vs 9.2 pack-years, p = 0.03)
  • Parenchymal abnormalities were seen in about 37% (28/75) of smokers or ex-smokers and about 23% (10/44) of nonsmokers; this difference was not statistically significant (p = 0.099)
  • In a multiple logistic regression controlling for pack-years, duration of exposure remained associated with parenchymal abnormalities (p = 0.004), as did smoking (p = 0.027)
  • No significant difference in lung function tests was found between workers with pleural lesions and those with normal pleura
  • Among nonsmokers, the 10 with parenchymal abnormalities had lower mean FVC than the 34 with normal parenchyma (78.2 vs 89.7% of predicted, p = 0.03)
  • Among smokers or ex-smokers, the 28 with parenchymal abnormalities had lower FEV1/FVC than the 47 with normal parenchyma (93.7 vs 100.2% of predicted, p = 0.005)
• The authors' conclusion: The authors concluded that HRCT abnormalities among asbestos workers are strictly related to asbestos exposure and may correlate with function impairment. They linked parenchymal abnormalities to decreased FVC in nonsmokers and reduced obstructive indices in smokers, without clinically evident disease.
• Limitations the authors state:
  • The sample size was probably not sufficient to show a statistically significant difference in the prevalence of parenchymal abnormalities between smokers and nonsmokers, which was not the primary objective
  • HRCT findings are not specific to asbestos

Topics

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

Medical terms in this study, explained in our Lexicon: Habit, High-Resolution CT (HRCT), Fibrosis, Asbestos Exposure, Latency, Chest X-Ray, Diffusing Capacity (DLCO), Pulmonary Function Test (PFT).

Related studies

• Findings from high resolution computed tomography of the lung and pleura of symptom free workers exposed to amosite who had normal chest radiographs and pulmonary function tests — S. Neri, A. Antonelli, et al. (1994)
• High resolution computed tomography and lung function in asbestos-exposed workers with normal chest radiographs — C.A. Staples, G. Gamsu, et al. (1989)
• Early detection of interstitial lung disease in asbestos exposed non-smoking workers by mid-expiratory flow rate and high resolution computed tomography — Z. Dujić, J. Tocilj, et al. (1991)
• Agreement between chest radiography and high-resolution computed tomography in diagnosing dust-related interstitial lung fibrosis — R.R. Tiwari (2015)
• The comparison of high-resolution computed tomography findings in asbestosis and idiopathic pulmonary fibrosis — M. Akira, K. Morinaga (2016)
• Relationships (I) of International Classification of High-resolution Computed Tomography for Occupational and Environmental Respiratory Diseases with the ILO International Classification of Radiographs of Pneumoconioses for parenchymal abnormalities — T. Tamura, N. Suganuma, et al. (2015)

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