Ellen Imbernon

Risk factors for upper-extremity musculoskeletal disorders in the working population.

OBJECTIVE To assess the relative importance of personal and occupational risk factors for upper-extremity musculoskeletal disorders in the working population. METHODS A total of 3,710 workers (58% men) participating in a surveillance program of musculoskeletal disorders in a French region in 2002-2005 were included. Upper-extremity musculoskeletal disorders were diagnosed by 83 trained occupational physicians performing a standardized physical examination. Personal factors and work exposure were assessed by a self-administered questionnaire. Statistical associations between musculoskeletal disorders, personal, and occupational factors were analyzed using logistic regression modeling. RESULTS A total of 472 workers experienced at least 1 upper-extremity musculoskeletal disorder. The risk of upper-extremity musculoskeletal disorders increased with age for both sexes (P < 0.001, odds ratio [OR] < or =4.9 in men and < or =5.0 in women), and in cases of prior history of upper-extremity musculoskeletal disorders (OR 3.1 and 5.0, respectively, P < 0.001). In men, upper-extremity musculoskeletal disorders were associated with obesity (OR 2.2, P = 0.014), high level of physical demand (OR 2.0, P < 0.001), high repetitiveness of the task (OR 1.5, P = 0.027), postures with the arms at or above shoulder level (OR 1.7, P = 0.009) or with full elbow flexion (OR 1.6, P = 0.006), and high psychological demand (OR 1.5, P = 0.005). In women, upper-extremity musculoskeletal disorders were associated with diabetes mellitus (OR 4.9, P = 0.001), postures with extreme wrist bending (OR 2.0, P < 0.001), use of vibrating hand tools (OR 2.2, P = 0.025), and low level of decision authority (OR 1.4, P = 0.042). CONCLUSION Personal and work-related physical and psychosocial factors were strongly associated with clinically diagnosed upper-extremity musculoskeletal disorders.

Why are manual workers at high risk of upper limb disorders? The role of physical work factors in a random sample of workers in France (the Pays de la Loire study).

Objective: To investigate the reasons for the excess risk of upper limb musculoskeletal disorders among manual workers compared with other workers in a random sample of 2656 French men and women (20–59 years old) participating in a study on the prevalence of work related upper limb disorders conducted by France’s National Institute of Health Surveillance. Methods: Prevalence ratios (PR) of physician-diagnosed musculoskeletal disorders of the shoulder, elbow, wrist, and hand (any of six leading disorders, rotator cuff syndrome, carpal tunnel syndrome) in manual versus non-manual workers were calculated using Cox regression models with a constant time of follow up and robust variance. Results: 11.3% of men and 15.1% of women were diagnosed with an upper limb disorder. The risk was especially high in manual workers (PRs: 1.40 to 2.10). Physical work factors accounted for over 50% of occupational disparities overall, 62% (men) to 67% (women) for rotator cuff syndrome, and 96% (women) for carpal tunnel syndrome. The authors calculated that under lower levels of physical work exposures, up to 31% of cases among manual workers could have been prevented. Conclusions: In working men and women, upper limb musculoskeletal disorders are frequent. Physical work exposures, such as repetitive and forceful movements, are an important source of risk and in particular account for a large proportion of excess morbidity among manual workers.

Work increases the incidence of carpal tunnel syndrome in the general population

The purpose of this study was to estimate the incidence of carpal tunnel syndrome (CTS) in a general population according to employment status and to assess the proportion of cases attributable to work. CTS occurring in patients aged 20–59 years living in the French Maine and Loire region were included prospectively from 2002 to 2004. Medical and occupation history was gathered by mailed questionnaire. Incidence rates of CTS and relative risks (RRs) of CTS were computed in relation to employment status. The attributable fractions of risk of CTS to work among the exposed persons (AFEs) were calculated. A total of 1168 patients (819 women, 349 men) were included during the 3‐year period. The mean incidence rate of CTS per 1000 person‐years was higher in employed than unemployed persons (1.7 vs. 0.8 in women and 0.6 vs. 0.3 in men). The excess risk of CTS was statistically significant for male (RR 4.2) and female (RR 3.0) blue‐collar workers and female lower‐grade white‐collar workers (RR 2.5). The AFE to work in general was 47% (95% confidence interval: 39–54) in women. AFEs reached higher values in female blue‐collar workers [67% (65–68)] and lower‐grade services, sales, and clerical white‐collar workers [61% (57–64)]. The AFE in male blue‐collar workers was 76% (72–80). These data show a higher incidence of CTS in the working than the non‐working population and suggest that a substantial proportion of CTS cases diagnosed in lower‐grade white‐collar and blue‐collar workers are attributable to work. Muscle Nerve, 2008

The French Musculoskeletal Disorders Surveillance Program: Pays de la Loire network

Objectives: An epidemiological surveillance system for work-related musculoskeletal disorders (MSDs) was implemented in 2002 in France’s Pays de la Loire region to assess the incidence and prevalence of MSDs in the general and working populations, identify levels of exposure to occupational risk factors and investigate the proportion of cases attributable to work exposure. Methods: The program combines (1) surveillance of sentinel health events in the general population (carpal tunnel syndrome (CTS) was the sentinel event for upper limb MSDs), (2) assessment of the prevalence of the main upper limb MSDs and their risk factors in the workplace based on a network of occupational physicians and (3) registration of the notification of work-related diseases (WRDs). Results: 1168 incident cases of CTS were included over a 3 year period. The estimated incidence of CTS was 1.00 per 1000 person-years in those aged 20–59 years (0.60 in men and 1.40 in women). The incidence rate was higher in employed than unemployed persons in the year of diagnosis (0.6 per 1000 vs 0.3 in men and 1.7 vs 0.8 in women). The occupational physician network noted high prevalence rates: 11% of men and 15% of women had at least one of the six main upper limb clinically-diagnosed MSDs. The WRD survey showed that MSDs represented 65% of notified WRDs. Conclusion: The Pays de la Loire program plays a significant role in informing the authorities and the public about the state of current MSDs. It is planned to extend it to a routine national surveillance program.

Occupational and non-occupational attributable risk of asbestos exposure for malignant pleural mesothelioma

Objectives To estimate the proportion of pleural mesothelioma cases that can be attributed to asbestos exposure in France including non-occupational exposure. Methods A population-based case-control study including 437 incident cases and 874 controls was conducted from 1998 to 2002. Occupational and non-occupational asbestos exposure was assessed retrospectively by two expert hygienists. ORs of pleural mesothelioma for asbestos-exposed subjects compared to non-exposed subjects, and population-attributable risk (ARp) of asbestos exposure were estimated using a conditional logistic regression. Results A clear dose-response relationship was observed between occupational asbestos exposure and pleural mesothelioma (OR=4.0 (99% CI 1.9 to 8.3) for men exposed at less than 0.1 f/mL-year vs 67.0 (99% CI 25.6 to 175.1) for men exposed at more than 10 f/mL-year). The occupational asbestos ARp was 83.1% (99% CI 74.5% to 91.7%) for men and 41.7% (99% CI 25.3% to 58.0%) for women. A higher risk of pleural mesothelioma was observed in subjects non-occupationally exposed to asbestos compared to those never exposed. The non-occupational asbestos ARp for these subjects was 20.0% (99% CI −33.5% to 73.5%) in men and 38.7% (99% CI 8.4% to 69.0%) in women. When considering all kinds of asbestos exposure, ARp was 87.3% (99% CI 78.9% to 95.7%) for men and 64.8% (99% CI 45.4% to 84.3%) for women. Conclusions Our study suggests that the overall ARp in women is largely driven by non-occupational asbestos exposure arguing for the strong impact of such exposure in pleural mesothelioma occurrence. Considering the difficulty in assessing domestic or environmental asbestos exposure, this could explain the observed difference in ARp between men and women.

Matgene: A Program to Develop Job-Exposure Matrices in the General Population in France

OBJECTIVES Matgéné is a program to develop job-exposure matrices (JEMs) adapted to the general population in France for the period since 1950. The aim is to create retrospective exposure assessment tools for estimating the prevalence of occupational exposure to various agents that can then be correlated to health-related parameters. METHODS JEMs were drawn up by a team of six industrial hygienists who based their assessments on available occupational measurement, economic and statistical data, and several thousand job descriptions from epidemiological studies performed in France since 1984. Each JEM is specific to one agent, assessing exposure for a set of homogeneous combinations (occupation × activity × period) according to two occupational classifications (ISCO 1968 and PCS 1994) and one economic activities classification (NAF 2000). The cells of the JEM carry an estimate of the probability and level of exposure. Level is estimated by the duration and intensity of exposure-linked tasks or by description of the tasks when exposure measurement data are lacking for the agent in question. The JEMs were applied to a representative sample of the French population in 2007, and prevalence for each exposure was estimated in various population groups. All documents and data are available on a dedicated website. RESULTS By the end of 2010, 18 JEMs have been developed and eight are under development, concerning a variety of chemical agents: organic and mineral dust, mineral fibers, and solvents. By implementation in the French population, exposure prevalences were calculated at different dates and for complete careers, and attributable risk fractions were estimated for certain pathologies. Some of these results were validated by comparison with those of other programs. DISCUSSION Initial Matgéné JEMs results are in agreement with the French and international literature, thus validating the methodology. Exposure estimates precision, however, vary between agents and according to the amount of exposure measurement data available. These JEMs are important epidemiological tools, and improving their quality will require investment in occupational health data harvesting, especially in the case of low-level exposures.

Evolution of pleural cancers and malignant pleural mesothelioma incidence in France between 1980 and 2005.

The evolution of pleural cancers and malignant pleural mesothelioma incidence in France between 1980 and 2005 was analysed using data derived from the French network of cancer registries (FRANCIM) and the French National Mesothelioma Surveillance Program (PNSM). Mesothelioma proportions in pleural cancers were calculated by diagnosis year in the 1980–2000 period. Our results suggest that the incidences of pleural cancer and mesothelioma levelled off in French men since 2000 and continued to increase in French women. A decrease of the annual pleural cancer incidence average in men was noticed (−3.4% of annual rate of change) between 2000 and 2005. The proportion of pleural cancers that were mesothelioma was unchanged between 1980 and 2003 with an average of 86%. The age standardised incidence rate of pleural mesothelioma remained relatively stable between 1998 and 2005 with a slight falling trend. For women, the age standardised incidence rate of pleural cancers and mesothelioma increased during the period 1998–2005. Additionally, the proportion of pleural cancers that were mesothelioma increased during the same period of time. Finally, the increased trend observed in the incidence of pleural mesothelioma and cancers in women is credibly due to their under diagnosis in the 1980–1997 period. The comparison between the French incidence and the American and British ones shows that the decreasing trend in incidence of mesothelioma and pleural cancers in French men since 2000 is potentially associated with a lower amphibole consumption and by the implementation of safety regulations at work from 1977.

Temporal patterns of occupational asbestos exposure and risk of pleural mesothelioma.

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 job–exposure 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.

Working conditions and depressive symptoms in the 2003 decennial health survey: the role of the occupational category

IntroductionThe aim of this study is to describe the associations between depressive symptoms and some working conditions according to broad occupational categories in France.MethodsThese data came from the decennial health survey conducted in 2003 in France by the National Institute for Statistics and Economics Studies (6,082 men, 5,521 women). The data collected included: depressive symptoms (Center for Epidemiological Studies-Depression Scale), psychosocial factors at work and potential confounding factors.ResultsAssociations between psychosocial work factors and depressive symptoms varied, according to occupational category and sex. Time pressure was significantly associated with depressive symptoms in the less advantaged occupational categories. The lack of job control was associated with depressive symptoms only in managers and associate professionals and technicians. Only low social support was systematically associated with depressive symptoms, regardless of occupational category.ConclusionThese results should be taken into account to adapt strategies of mental health disorders prevention at work, for a better efficacy.

Occupations and Industries in France at High Risk for Pleural Mesothelioma: A Population-Based Case-Control Study (1998-2002)

BACKGROUND Occupational exposure to asbestos, widely used in various industries for decades, is the most important risk factor for pleural mesothelioma. We report here the ranking of occupations and industries in France at high risk for this cancer among men and women. METHODS A population-based case-control study, conducted from 1998 to 2002, included 462 cases (80.3% men) and 897 controls. Data were collected in face-to-face interviews with a standardized questionnaire. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for each occupation and industry; subjects never employed in each category were the reference. RESULTS For men, risks were high for several occupations and industries. Besides the expected high risks for non-metallic mineral product makers and manufacturing asbestos products, occupations such as plumbers (OR = 5.57, 95% CI: 2.90-10.69), sheet-metal workers, welders, metal molders, coremakers, and cabinetmakers were also at high risk. Elevated risks were found in the industries of shipbuilding (OR = 9.13, 95% CI: 5.20-16.06) and construction, but also in the manufacturing of metal products, chemicals, and railroad and aircraft equipment. The results for women showed increased but not significant risks in several occupational activities. CONCLUSIONS This report provides new insight into the epidemiology of mesothelioma, confirming risks for occupational activities reported earlier and pointing out risks in activities never previously reported. It offers guidance to authorities for the compensation of asbestos victims and for prevention in at-risk activities still involving asbestos-containing products.