[Compensation for occupational diseases after tomodensitometry screening for benign pleuro-pulmonary disease in a multiregional post-occupational medical surveillance program of asbestos-exposed retired workers]. / Déclaration et reconnaissance en maladie professionnelle après dépistage tomodensitométrique de maladies pleuropulmonaires bénignes dans le programme multirégional de surveillance postprofessionnelle de personnes exposées à l'amiante.

BACKGROUND: Underreporting of occupational diseases related to asbestos exposure remains a matter of concern in France. The aim of this study was to evaluate the number of claims for compensation for asbestos-related non-malignant pulmonary or pleural occupational disease in subjects having undergone a chest CT-scan in a multiregional screening programme. METHODS: Among the 5444 voluntary retired asbestos-exposed subjects recruited in four regions between 2003 and 2005 who had undergone a chest CT-scan, the number of claims for compensation for an asbestos-related pulmonary or pleural benign disease was analysed in 2006 and 2010. RESULTS: Following CT-scan screening, 17.2% of participants were acknowledged as presenting with an asbestos-related non-malignant occupational disease, essentially pleural plaques, by the French National Health Insurance fund. Underreporting decreased as duration of follow-up after CT-scan increased. Nevertheless, 4 years after CT-scan, underreporting was still as high as 36% for subjects identified as presenting with pleural plaques. Mean duration between the date of CT-scan and the date of recognition as occupational disease was 7.4 months, shorter in cases where screening was coordinated by specialized centres. CONCLUSION: A plan of action for an easier claiming process for compensation of asbestos-related diseases is desired. This could probably be obtained through improved sensitization of physicians engaged in the follow-up of asbestos-exposed subjects, and by standardization of the interpretation and reporting of asbestos-related abnormalities observed on chest CT-scans.

[The different pleuro-pulmonary pathologies related to asbestos: definitions, epidemiology and evolution]. / Les différentes pathologies pleuropulmonaires liées à l'amiante: définitions, épidémiologie et évolution.

Pleural plaques (fibrosis of the parietal pleura) are sometimes seen following light exposure. Their prevalence may reach 70% in heavily exposed populations. Fibrosis of the visceral pleura is much less common and it is not specifically related to asbestos. The incidence of asbestosis (pulmonary fibrosis induced by asbestos exposure) is diminishing in France. According to the data of the National Programme for the Surveillance of Mesothelioma, the annual number of cases of pleural mesothelioma varied from 646 to 800 for the period 1998-2003. Primary lung cancer due to asbestos does not have specific clinical, radiological or anatomical-pathological features. The number of cases attributable to asbestos has been estimated as between 2086 and 4172 for 1999. A report of the National Academy of Medicine, the Academy of Sciences and the International Centre of Cancer Research has calculated the incidence of primary lung cancer due to asbestos in 2000 as 969 for men and 133 for women. The risk of primary lung cancer is increased in populations exposed to asbestos even in the absence of radiological signs of pulmonary fibrosis. For an identical total exposure, asbestosis increases the risk of primary lung cancer. On the basis of radiological studies, pleural plaques are associated with an increased risk of lung cancer and mesothelioma. For identical levels of total asbestos exposure, it has not been established that the presence of pleural plaques increases the risk of developing thoracic cancer.

Pulmonary nodules detected by thoracic computed tomography scan after exposure to asbestos: diagnostic significance.

OBJECTIVE: To analyse the relationship between pulmonary nodules detected by radiologists using computed tomography and cumulative exposure to asbestos or asbestos-related pleuro-pulmonary diseases in 5662 asbestos-exposed subjects, and the relationship between pulmonary nodules and thoracic cancer, to determine whether a specific surveillance strategy based on cumulative asbestos exposure should be adopted. DESIGN: Standardised incidence and mortality ratios (SIR) for lung cancer and pleural mesothelioma were calculated in patients with and without mention of pulmonary nodules and compared using comparative morbidity figures. RESULTS: A significant excess incidence of primary lung cancer and pleural mesothelioma was observed among subjects presenting with pulmonary nodule(s) (SIR respectively 1.95, 95%CI 1.22-2.95, and 11.88, 95%CI 3.20-30.41). However, there was no significant relationship between pulmonary nodules mentioned by radiologists and cumulative asbestos exposure or between pulmonary nodules and the presence of asbestos-related benign diseases. CONCLUSIONS: This study confirms the expected excess prevalence of lung cancer in subjects presenting with pulmonary nodules according to the radiologist's report, and shows the absence of relationship between the presence of nodules and level of cumulative asbestos exposure. Our study therefore offers no argument in favour of specific surveillance modalities based on estimated cumulative asbestos exposure.

Asbestos-related cancer risk in patients with asbestosis or pleural plaques.

INTRODUCTION: The relationships between benign asbestos-related diseases (asbestosis and pleural plaques) and thoracic cancers are still debated. The aim of this paper was to review the epidemiological data relevant to this issue. CURRENT KNOWLEDGE: Published studies show a significant relationship between occupational exposure to asbestos and lung cancer risk, even in the absence of abnormalities consistent with asbestosis on the postero-anterior chest x-ray. For a given cumulative asbestos exposure, the presence of radiographic evidence of asbestosis is associated with an increased risk of lung cancer. Among asbestos-exposed individuals, those having radiographic evidence of pleural plaques are at increased risk for lung cancer and pleural mesothelioma, compared to the general population. However, there is no evidence that pleural plaque confers an increased risk of lung cancer or pleural mesothelioma within a population of individuals having the same cumulative asbestos exposure. PERSPECTIVES: The studies identified for this review relied only on chest radiograph data. Studies involving accurate evaluations of asbestos exposure and computed tomography of the chest are needed. CONCLUSION: Currently available data indicate that patient follow-up modalities should be dictated solely by the estimated cumulative asbestos exposure and not by the existence of pleural plaques.

[Exposure to asbestos and the indoor environment]. / Situations d'exposition à l'amiante et environnement intérieur.

A link between the inhalation of asbestos fibres and the outcome of benign and malignant respiratory diseases has been established from numerous epidemiological data in occupational settings. Occupational exposure limit values have been established with a gradual lowering of these over time. Conversely, there are few epidemiological data dealing with exposure in the indoor environment. However, numerous materials and products containing asbestos (MPCA) are present in the indoor environment, due to their widespread use in the construction sector in the years between 1960 and 1990. The regulations were changed from the late 1990s, leading to a systematic inventory of the presence of asbestos-containing materials in buildings. The aim of this manuscript is to clarify the different types of MPCA encountered in the indoor environment, to describe the techniques used to highlight asbestos depending on the nature of the materials, the regulatory requirements relating to asbestos in non-occupational situations, and to update on the state of knowledge on asbestos-related diseases in the indoor environment.

[Asbestos-related cancer risk in the presence of asbestosis or pleural plaques]. / Risque de cancer lié à l'amiante en présence d'asbestose ou de plaques pleurales.

INTRODUCTION: The relationships between benign asbestos-related diseases (asbestosis and pleural plaques) and thoracic cancers are still debated. The aim of this paper is to analyse epidemiological data which investigate this topic. STATE OF THE ART: Published studies show that there is a significant relationship between occupational exposure to asbestos and lung cancer risk, even in the absence of abnormalities consistent with asbestos exposure on postero-anterior chest x-ray. In subjects with occupational exposure to asbestos, an increased risk of lung cancer and pleural mesothelioma is observed in subjects with pleural plaques on chest x-ray, in comparison with the general population. In exposed subjects with similar cumulative exposure to asbestos, it is not demonstrated that pleural plaques are associated with an increased risk of lung cancer or pleural mesothelioma. PERSPECTIVES: All the analysed studies are only based on radiographic data. Their results must be confirmed by additional studies including a rigorous evaluation of the cumulative exposure to asbestos and chest CT-scans. CONCLUSION: In the present state of knowledge, isolated pleural plaques do not justify specific medical surveillance, as compared to that required by the mere estimated cumulative exposure to asbestos.

Pleural plaques and asbestosis: dose- and time-response relationships based on HRCT data.

Most studies on asbestos-related diseases are based on chest radiographs, and dose-response relationships are still controversial. The aim of this study was to describe the most relevant parameters of asbestos exposure linked to pleural plaques and asbestosis diagnosed by high-resolution computed tomography (HRCT). A large screening programme including systematic HRCT examinations was organised from 2003 to 2005 in France for formerly asbestos-exposed workers. The time since first exposure (TSFE), level, duration and cumulative exposure to asbestos were used in adjusted unconditional logistic regression to model the relationships of the two diseases. Analysis of a population of 5,545 subjects demonstrated that TSFE (p<0.0001) and cumulative exposure (p = 0.02) (or level, depending on the models used), were independently associated with the frequency of pleural plaques. Only cumulative exposure (p<0.0001) or level of exposure (p = 0.02) were significantly associated with asbestosis. All trend tests were significant for these parameters. To date and to our knowledge, this study is the largest programme based on HRCT for the screening of asbestos-exposed subjects. Both time-response and dose-response relationships were demonstrated for pleural plaques, while only dose-response relationships were demonstrated for asbestosis. These parameters must be included in the definition of high-risk populations for HRCT-based screening programmes.

[Etiology, epidemiology, biology. Occupational respiratory cancers]. / Cancers respiratoires professionnels.

Lung cancer and pleural mesothelioma are the most common occupational cancers. Recent epidemiological studies have estimated that the fraction attributable to occupational factors varies from 13 to 29% for lung cancer in men and is about 85% for pleural mesothelioma in men. Previous occupational exposure to asbestos is the most common occupational exposure in these cancers. Mesothelioma immediately leads the clinician to look for past asbestos exposure. In contrast, the search for an occupational exposure that should be routine in all cases of lung cancer, is generally more difficult because of the number of occupational aetiological factors and the absence of criteria that allow distinction of an occupational cancer from a tobacco related one. Therefore attention should be paid to the identification of occupational exposure in order to set up primary prevention programmes to prevent exposure still present in the working environment and, on the other hand, to identify the subjects entitled to the acknowledgement of occupational disease and/or to obtain the compensation available to asbestos victims.

[Occupational respiratory cancers]. / Cancers respiratoires professionnels.

Lung cancer and pleural mesothelioma are the most common occupational cancers. Recent epidemiological studies have estimated that the fraction attributable to occupational factors varies from 13 to 29% for lung cancer in men and is about 85% for pleural mesothelioma in men. Previous occupational exposure to asbestos is the most common occupational exposure in these cancers. Mesothelioma immediately leads the clinician to look for past asbestos exposure. In contrast, the search for an occupational exposure that should be routine in all cases of lung cancer, is generally more difficult because of the number of occupational aetiological factors and the absence of criteria that allow distinction of an occupational cancer from a tobacco related one. Therefore attention should be paid to the identification of occupational exposure in order to set up primary prevention programmes to prevent exposure still present in the working environment and, on the other hand, to identify the subjects entitled to the acknowledgement of occupational disease and/or to obtain the compensation available to asbestos victims.

Computed tomography findings in urban transportation workers with low cumulative asbestos exposure.

OBJECTIVE: To assess the frequency of computed tomography (CT) scan pleural and interstitial changes in a population of urban transportation workers with low cumulative exposure to asbestos, and to measure inter-reader agreement. DESIGN: A total of 269 male volunteers (mean age 54.0 +/- 2.3 years, mean estimated cumulative exposure index 1.7 +/- 2.3 fibres/ml-years), underwent a CT scan which was read independently by three experienced readers, with further consensus reading in case of pleural or parenchymal abnormalities. Inter-reader agreement was assessed by means of Kappa statistic. RESULTS: On consensus reading, four subjects had interstitial opacities, three had diffuse pleural thickening and 26 (9.7%) had pleural plaques that were unilateral in 65% of cases and < or =2 mm thick in 54% of cases. No correlation was observed between pleural plaques and latency, duration of exposure or cumulative exposure. The inter-reader agreement for the detection of pleural abnormalities was fair. CONCLUSION: In this relatively young population with low cumulative exposure to asbestos, the prevalence of pleural abnormalities was low. These abnormalities were very limited in thickness and extent, leading to marked inter-reader variability and making it difficult to assess their relationship to asbestos exposure.

[Computed tomographic atlas of benign asbestos related pathology]. / Atlas iconographique tomodensitométrique des pathologies bénignes de l'amiante.

The demonstration by computed tomography of abnormalities related to asbestos is essential for the recognition of industrial disease, the compensation of which has considerable economic consequences. The use of computed tomography, the most reliable technique for the detection of pleuro-parenchymatous abnormalities related to asbestos exposure, has increased considerably in France since the publication of the results of a consensus conference in Paris in 1999. Since that time, developments in CT technology have noticeably modified the protocols of investigation and increased the sensitivity of the detection of pleural and interstitial parenchymatous abnormalities and of nodules. The technical recommendations and those for the interpretation of pleural and parenchymatous abnormalities need to be well known. They are presented in the form of an atlas that gives detailed criteria for asbestosis, pleural plaques and pleural fibrosis. The diagnosis of pleural plaques depends on the combination of clear limits at the pleural and pulmonary interface, typical topography and multiple, bilateral localization. In the context of asbestos exposure the plaques are characteristic of this exposure, unlike diffuse pleural thickening, crow's feet images, parenchymatous bands and entrapped atalectasis. The writing of the radiological report would be most appropriate on this basis.

[Computed tomographic atlas of benign asbestos related pathology]. / Atlas iconographique tomodensitométrique des pathologies bénignes de l'amiante.

The demonstration by computed tomography of abnormalities related to asbestos is essential for the recognition of industrial disease, the compensation of which has considerable economic consequences. The use of compute tomography, the most reliable technique for the detection of pleuro-parenchymatous abnormalities related to asbestos exposure, has increased considerably in France since the publication of the results of a consensus conference in Paris in 1999. Since that time, developments in technology have noticeably modified the protocols of investigation and increased the sensitivity of the detection of pleural and interstitial parenchymatous abnormalities and of nodules. The technical recommendations and those for the interpretation of pleural and parenchymatous abnormalities need to be well known. They are presented in the form of an atlas that gives detailed criteria for asbestosis, pleural plaques and pleural fibrosis. The diagnosis of pleural plaques depends on the combination of clear limits at the pleural and pulmonary interface, typical topography and multiple, bilateral localization. In the context of asbestos exposure the plaques are characteristic of this exposure, unlike diffuse pleural thickening, crow's feet images, parenchymatous bands and entrapped atalectasis. The writing of the radiological report would be most appropriate on this basis.

Factors associated with severity of occupational asthma with a latency period at diagnosis.

BACKGROUND: Severity of occupational asthma at diagnosis is an important prognostic factor. The aim of this study was to determine which factors affect the severity of occupational asthma with a latency period at diagnosis. METHODS: The study population consisted of 229 consecutive subjects with occupational asthma with a latency period recruited by four occupational health departments and divided into two groups according to the severity of the disease at diagnosis. The moderate-severe (FEV(1) <70% predicted, or PD(20) methacholine /=70% predicted and PD(20) methacholine >300 microg, n = 128) groups were compared in terms of clinical and demographic parameters. Multivariate analysis using logistic regressions was performed to examine factors associated with asthma severity. RESULTS: Duration of symptoms before diagnosis was significantly longer in the moderate-severe group (mean +/- SD: 6.3 +/- 6.8 years vs 3.4 +/- 4.4 years, P < 0.001). Sex ratio, age, atopy, smoking habits, duration of exposure before symptoms, and molecular weight of the causal agent were not significantly different between the two groups. On multivariate analysis, only duration of symptoms before diagnosis was associated with asthma severity (aOR = 1.12, 95% CI 1.05-1.18, P < 0.001). CONCLUSIONS: Severity of occupational asthma with a latency period at diagnosis was associated with duration of symptoms before diagnosis, but not with the type of causal agent. This finding emphasizes the need for early diagnosis and avoidance of exposure.

[Occupational chronic obstructive pulmonary disease: a poorly understood disease]. / La bronchopneumopathie chronique obstructive professionnelle: une maladie méconnue.

INTRODUCTION: According to several recent population-based studies 15-20% of chronic obstructive pulmonary disease (COPD) is work related. BACKGROUND: The occupational fields in which a causal relationship is established are the mining industry, construction and public works, iron and steel, textiles, grain (silo workers), dairy and pig farming. The main causative substances are silica, coal dust, cotton dust, grain dust and endotoxins. VIEWPOINT: Knowledge of the occupational causes of COPD is important for both prevention and compensation. CONCLUSIONS: The undertaking of a complete and rigorous occupational questionnaire is essential for all patients with COPD.

[Is the severity of occupational asthma related to the molecular weight of the allergen?]. / La sévérité de l'asthme professionnel est-elle liée au poids moléculaire de l'allergène?

INTRODUCTION: The aim of the study was to compare the characteristics of occupational asthma (OA) resulting from sensitisation to allergens of high (HMW) or low (LMW) molecular weight. METHODS: All new cases of allergic OA seen in an occupational health department between January 2001 and March 2004 were included. The patients underwent a standardised assessment including a questionnaire, skin tests, spirometry and measurement of non-specific bronchial reactivity. They were divided into 2 groups depending on the molecular weight of the causal agent (groups HMW and LMW). RESULTS: 77 patients were included, 30 in the HMW group and 47 in the LMW group. No significant difference in severity at the time of diagnosis was found between the two groups (symptoms, spirometry, PD20 methacholine) but the time between the first symptoms and diagnosis was longer in the HMW group (7.1 +/- 7.8 years against 3.2 +/- 4.1 years, p = 0.01). Atopy was more common in the HMW group (57% vs. 27%, p = 0.01). CONCLUSION: The severity of OA at the time of diagnosis does not appear to be influenced by the molecular weight of the causal agent.