Temporal patterns of occupational asbestos exposure and risk of pleural mesothelioma

Abstract

Asbestos is the primary cause of pleural mesothelioma (PM). The objective of this study was to elucidate the importance of different temporal patterns of occupational asbestos exposure on the risk of PM using case-control data in male subjects.Cases were selected from a French case-control study conducted in 1987-1993 and the French National Mesothelioma Surveillance Program in 1998-2006. Population controls were frequency matched to cases by year of birth. Occupational asbestos exposure was evaluated with a jobexposure matrix. The dose-response relationships were estimated using restricted cubic spline functions in logistic regression models.A total of 2,466 ever-asbestos-exposed males (1,041 cases and 1,425 controls) were used. After adjustment for intensity and total duration of occupational asbestos exposure, the risk of PM was lower for subjects first exposed after the age of 20 yrs and continued to increase until 30 yrs after cessation of exposure. The effect of total duration of exposure decreased when age at first exposure and time since last exposure increased.These results, based on a large population-based case-control study, underline the need to take into account the temporal pattern of exposure on risk assessment.

Welding, a risk factor of lung cancer: the ICARE study

“…However, to improve the definition of the not exposed group and because it was not possible to be sure that participants had answered all requested specific questionnaires, we additionally applied an asbestos-specific job-exposure matrix (JEM) developed according to the combination of ISCO and NAF codes (available on demand from dst-matgene@invs.sante.fr) 12 13. Briefly, for each job i, the asbestos-JEM assigned a probability (percentage of workers exposed in the considered combination: none or less than 1% of workers; <5%; 5% to 30%; 30% to 70% and >70%), a frequency (percentage of working time during which a participant would be exposed (<5%, 5% to 30%; 30% to 70% ≥70%) and an intensity (in fibres/mL: <0.01; 0.01 to 0.1; 0.1 to 1;1 to 10; >10) of exposure related to specific tasks.…”

Response to: ‘Dose–time–response association between occupational asbestos exposure and pleural mesothelioma’ by Lacourt et al

“…The study by Lacourt reported in a recent issue of Occup Environ Med 1 does not satisfy two fundamental requirements of the design and conduct of a case–control study: these limitations invalidate its results and those of other reports based on the same dataset 2…”

Are children more vulnerable to mesothelioma than adults? A comparison of mesothelioma risk among children and adults exposed non-occupationally to blue asbestos at Wittenoom

“…Among men exposed for a duration of 30 years or longer, compared with those first exposed at age 10 years, the OR for a man first exposed at age 15 years was 1.1 (95% CI 0.3 to 3.8). The OR for a man first exposed at age 30 years was 0.2 (95% CI 0.0 to 0.7), suggesting a possible exposure-response relationship with age at first exposure, although the relationship was less pronounced for those with less than 30 years’ duration of exposure 20. Similarly, Rake et al reported a mesothelioma risk that was increased among both women and men (OR 2.0, 95% CI 1.3 to 3.2) who had lived with a high-risk worker before the age of 30, although it is not clear how many of those 50 cases were aged less than 15 years at first exposure 21.…”