Interstitial Lung Abnormalities Detected by CT in Asbestos-Exposed Subjects Are More Likely Associated to Age

OBJECTIVE: the aim of this study was to evaluate the association between interstitial lung abnormalities, asbestos exposure and age in a population of retired workers previously occupationally exposed to asbestos. METHODS: previously occupationally exposed former workers to asbestos eligible for a survey conducted between 2003 and 2005 in four regions of France, underwent chest CT examinations and pulmonary function testing. Industrial hygienists evaluated asbestos exposure and calculated for each subject a cumulative exposure index (CEI) to asbestos. Smoking status information was also collected in this second round of screening. Expert radiologists performed blinded independent double reading of chest CT-scans and classified interstitial lung abnormalities into: no abnormality, minor interstitial findings, interstitial findings inconsistent with UIP, possible or definite UIP. In addition, emphysema was assessed visually (none, minor: emphysema 50% of the lung). Logistic regression models adjusted for age and smoking were used to assess the relationship between interstitial lung abnormalities and occupational asbestos exposure. RESULTS: the study population consisted of 2157 male subjects. Interstitial lung abnormalities were present in 365 (16.7%) and emphysema in 444 (20.4%). Significant positive association was found between definite or possible UIP pattern and age (OR adjusted =1.08 (95% CI: 1.02-1.13)). No association was found between interstitial abnormalities and CEI or the level of asbestos exposure. CONCLUSION: presence of interstitial abnormalities at HRCT was associated to aging but not to cumulative exposure index in this cohort of former workers previously occupationally exposed to asbestos

Deep Learning for the Automatic Quantification of Pleural Plaques in Asbestos-Exposed Subjects

OBJECTIVE: This study aimed to develop and validate an automated artificial intelligence (AI)-driven quantification of pleural plaques in a population of retired workers previously occupationally exposed to asbestos. METHODS: CT scans of former workers previously occupationally exposed to asbestos who participated in the multicenter APEXS (Asbestos PostExposure Survey) study were collected retrospectively between 2010 and 2017 during the second and the third rounds of the survey. A hundred and forty-one participants with pleural plaques identified by expert radiologists at the 2nd and the 3rd CT screenings were included. Maximum Intensity Projection (MIP) with 5 mm thickness was used to reduce the number of CT slices for manual delineation. A Deep Learning AI algorithm using 2D-convolutional neural networks was trained with 8280 images from 138 CT scans of 69 participants for the semantic labeling of Pleural Plaques (PP). In all, 2160 CT images from 36 CT scans of 18 participants were used for AI testing versus ground-truth labels (GT). The clinical validity of the method was evaluated longitudinally in 54 participants with pleural plaques. RESULTS: The concordance correlation coefficient (CCC) between AI-driven and GT was almost perfect (>0.98) for the volume extent of both PP and calcified PP. The 2D pixel similarity overlap of AI versus GT was good (DICE = 0.63) for PP, whether they were calcified or not, and very good (DICE = 0.82) for calcified PP. A longitudinal comparison of the volumetric extent of PP showed a significant increase in PP volumes (p < 0.001) between the 2nd and the 3rd CT screenings with an average delay of 5 years. CONCLUSIONS: AI allows a fully automated volumetric quantification of pleural plaques showing volumetric progression of PP over a five-year period. The reproducible PP volume evaluation may enable further investigations for the comprehension of the unclear relationships between pleural plaques and both respiratory function and occurrence of thoracic malignancy

Environ Res

OBJECTIVE: To investigate the association between occupational exposures to carbonaceous unintentionally emitted nanoscale particles (UNPs) during pregnancy and the child's language development and behaviour at two years old. METHODS: Using data from the French Longitudinal Study of Childhood - ELFE, we selected mothers who worked during pregnancy and their children. Exposure to carbonaceous UNPs was assessed by the MatPUF (job-exposure matrix for ultrafine particles). Children's lexical development was analysed using 'the Mac Arthur - Bates communicative development inventories-words and sentences-short form' (MB-CDI) in a multivariate binary logistic regression. Their risk for autism spectrum disorders was studied using 'the Modified-CHecklist for Autism in Toddler' (M-CHAT) according to the recommended thresholds (low risk = 0-2; intermediate risk = 3-6 and high risk = 7-23) in unordered multinomial logistic regression models. RESULTS: Maternal occupational exposure to carbonaceous UNPs was associated with delayed child language development (ORadj: 1.34; 95 % CI: 1.00, 1.80) but not with behavioural disorders (autism spectrum disorders) at two years old. CONCLUSION: This is the first epidemiological study to show a significant association between maternal occupational exposure to carbonaceous nanoscale particles and child language development at 2 years old

Environ Int

OBJECTIVES: To investigate the association between maternal occupational exposures to nanoscale particles (NPs) during pregnancy and small for gestational age (SGA). METHODS: This study included 11,224 mothers and singleton birth pairs from the French Longitudinal Study of Children (ELFE cohort), which included infants born after 33weeks of gestation or more in continental France in 2011. Mothers who did not work during pregnancy were excluded from the analyses. Maternal occupational exposures to NPs was estimated using a job-exposure matrix for the probability (>50%: occupationally exposed group, n=569; 0%: occupationally non-exposed group, n=9113; between these two thresholds: uncertain group, n=1542) and frequency of exposure. Associations were estimated from multivariate logistic regression models for occupationally exposed vs occupationally unexposed groups in a first analysis, and with the frequency-weighted duration of work for the occupationally exposed group only in a second analysis. RESULTS: Among working mothers, 5.1% were occupationally exposed to NPs. Maternal occupational exposures to NPs was associated with SGA (ORa=1.63, 95% CI: 1.22, 2.18). The frequency-weighted duration of work for the occupationally exposed group (n=569) was not associated with SGA (ORa=1.02, 95% CI: 0.97, 1.08) in adjusted analyses. CONCLUSIONS: These results, showing a significant association between occupational exposures to NPs and SGA, should encourage further studies to examine the adverse effect of NPs exposure on fetal development

Head and neck cancer and asbestos exposure

International audienceOBJECTIVES: The aim of this study was to analyse, within a French cohort of workers previously occupationally exposed to asbestos, incidence and mortality from various sites of head and neck cancers (larynx excluded) and to examine the potential link of these cancers with pleural plaques.METHODS: A 10-year follow-up study was conducted in the 13 481 male subjects included in the cohort between October 2003 and December 2005. Asbestos exposure was assessed by industrial hygienist analysis of a standardised questionnaire. The final cumulative exposure index (CEI; in equivalent fibres.years/mL) for each subject was calculated as the sum of each employment period's four-level CEI. The number of head and neck cancers recorded by the National Health Insurance fund was collected in order to conduct an incidence study. Complementary analysis was restricted to men who had performed at least one chest CT scan (N=4804). A mortality study was also conducted. We used a Cox model with age as the time axis variable adjusted for smoking, time since first exposure, CEI of exposure to asbestos and pleural plaques on CT scans.RESULTS: We reported a significant dose-response relationship between CEI of exposure to asbestos and head and neck cancers after exclusion of laryngeal cancers, in the mortality study (HR 1.03, 95% CI (1.01 to 1.06) for an increase of 10 f.years/mL) and a close to significant dose-response relationship in the incidence study (HR 1.02, 95% CI (1.00 to 1.04) for an increase of 10 f.years/mL). No statistically significant association between pleural plaques and head and neck cancer incidence was observed.CONCLUSIONS: This large-scale study suggests a relationship between asbestos exposure and head and neck cancers, after exclusion of laryngeal cancers, regardless of whether associated pleural plaques were present

Chest

BACKGROUND: Previous studies have inconsistently reported associations between Refractory Ceramic Fibers (RCF) or Mineral Wool Fibers (MWF) and the presence of pleural plaques (PP). Moreover, all these studies were based on Chest X-Ray, known to be associated with a poor sensitivity for the diagnosis of PP. RESEARCH QUESTION: Does the risk of pleural plaques increase with cumulative exposure to RCF, MWF and silica ? and if yes, do these dose-response relationships depend on the co-exposure to asbestos or conversely, are the dose-response relationships for asbestos modified by co-exposure to RCF, MWF and silica ? STUDY DESIGN AND METHODS: Volunteer workers were invited to participate in a CT-scan screening program for asbestos-related diseases in France. Asbestos exposure was assessed by industrial hygienists and exposure to RCF, MWF and silica was determined by using Job-Exposure Matrices. A Cumulative Exposure Index (CEI) was then calculated for each subject and separately for each of the 4 mineral particle exposures. All available CT-scans were submitted to randomized, double reading by a panel of radiologists. RESULTS: In this cohort of 5,457 subjects, we found a significant dose-response relationships, after adjustment for asbestos exposure between CEI to RCF or MWF and the risk of PP (OR= 1.29 [1.00-1.67] and OR= 1.84 [1.49-2.27] for the highest CEI quartile respectively). Moreover, significant interactions were found between asbestos on one side and respectively MWF or RCF on the other side. INTERPRETATION: This study suggests the existence of a significant association between exposure to RCF and MWF and the presence of PP in a large population previously exposed to asbestos and screened by CT-scan