Do pleural plaques produce symptoms? A brief report

Our plain-English summary of Do pleural plaques produce symptoms? A brief report, by B. Järvholm, S. Larsson (Journal of Occupational Medicine., 1988).

The study

• Authors: B. Järvholm, S. Larsson
• Journal: Journal of Occupational Medicine.
• Published: 1988;30(4):345-7
• Cited by: 20 articles, as counted by NIH iCite
• Read it: PubMed
• In J-M's library: Johns-Manville's company medical library held a copy (J-M no. 000233).

Abstract

The occurrence of symptoms due to pleural plaques was studied by means of a questionnaire administered to asbestos-exposed workers participating in a health-screening program. One hundred thirty subjects who were found to have pleural plaques were compared with 1,103 control subjects who had no plaques and showed no changes on x-ray examination. No difference in occurrence of thoracic pain was found between the two groups. Dyspnea was more common among patients with pleural plaques, who also tended to have lower lung function values. There was a good correlation between reported dyspnea and lung function. The increased number of complaints of dyspnea among patients with pleural plaques could not be explained by differences in age or in smoking habits. It is suggested that dyspnea in patients with pleural plaques is caused by sub-roentgenologic fibrosis.

In plain English

This Swedish study asked whether pleural plaques cause symptoms. It used a health-screening program for asbestos-exposed workers in the Gothenburg area, which had 4,268 participants. The analysis covered men aged 40 to 65 who met selection criteria that excluded signs of heart disease. There were 130 men with pleural plaques on chest x-ray and 1,103 controls with no x-ray changes. Workers filled in a symptom questionnaire before their x-ray and breathing tests. Chest pain was not more common among men with plaques. Breathlessness (dyspnea) was more common. The mildest grade was reported by 19.2% of men with plaques and 12.6% of controls, a statistically significant difference. After accounting for age and smoking, the rate ratio for this grade was 1.5 but was no longer statistically significant. Men with plaques tended to have slightly lower lung function. Men reporting breathlessness also had lower lung function than men who did not. The authors concluded that plaques seem associated with breathlessness, most probably because of coexisting fibrosis too slight to show on x-ray, not the plaques themselves.

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 comparison within a health-screening program (brief report), using a self-administered symptom questionnaire, chest x-rays and spirometry
• Who was studied: Asbestos-exposed workers in a screening program in the Gothenburg area, Sweden, which the National Board of Social Health and Welfare recommended in 1976. Of 4,268 participants (4,155 men), 242 had pleural plaques. The analysis was restricted to men aged 40 to 65 without signs of cardiac disease: 130 men with pleural plaques and 1,103 controls with no x-ray evidence of plaques. Men with plaques were somewhat older. 43% of men with plaques and 39% of controls were current smokers.
• Exposure: Occupational asbestos exposure; fiber types not specified. 89% of men with plaques and 82% of controls had at least 5 years of continuous exposure. The authors described exposure as not extreme, with several men exposed to moderate or low doses (for example in car repairing or construction).
• Main results:
  • There was no increase in reported dull pain or sudden, sharp pain in the chest among men with pleural plaques compared with controls.
  • Dyspnea was more frequent among men with plaques. For dyspnea grade I, 19.2% of men with plaques reported it versus 12.6% of controls (crude rate ratio 1.5, P less than .05). The differences for grades II and III were not significant because numbers were small.
  • After stratifying for age and smoking (Mantel-Haenszel), the prevalence rate ratio for dyspnea grade I comparing men with and without plaques was 1.5, with P greater than .05 (not statistically significant).
  • Persons with dyspnea had somewhat impaired respiratory function compared with those without dyspnea. For dyspnea grade II, the differences were significant at P less than .01.
  • Men with plaques showed a small but consistent decrease in respiratory function compared with controls, with vital capacity somewhat more affected than forced expiratory volume in 1 second.
• The authors' conclusion: The authors concluded that they found no evidence that pleural plaques cause chest pain. They concluded that plaques seem to be associated with dyspnea, which they considered most probably due to coexisting subroentgenologic fibrosis (fibrosis not visible on x-ray) and not to the plaques as such.
• Limitations the authors state:
  • The wording of the questions did not exclude the possibility that pleural plaques cause slight discomfort.
  • After adjusting for age and smoking, statistical power decreased and the rate ratio was no longer significantly different from 1.0. Men with dyspnea grade II were too few for a similar analysis.
  • Men with plaques probably had slightly higher asbestos exposure than controls.

Topics

The National Library of Medicine indexes this study under subjects our site covers: Pleural plaques and thickening.

Medical terms in this study, explained in our Lexicon: Pleural Plaques, Dyspnea, Habit, Fibrosis.

Related studies

• Asbestos-related pleural diseases: dimensional criteria are not appropriate to differentiate diffuse pleural thickening from pleural plaques — J. Ameille, M. Matrat, et al. (2004)
• Pleural plaques and respiratory function — B. Järvholm, A. Sandén (1986)
• Pleural determinants of restrictive lung function and respiratory symptoms in an asbestos-exposed population — P.H. Wright (1993)
• Longitudinal analysis of respiratory symptoms in population studies with a focus on dyspnea in marine transportation workers — V.H. Arrandale, M. Koehoorn, et al. (2009)
• Taking a retrospective look at asbestos-related thoracic disease produces interesting results — E.B. Gottschall (2010)
• Pleural plaques and asbestosis: dose- and time-response relationships based on HRCT data — C. Paris, S. Thierry, et al. (2009)

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