Description: Objective The objective of the study was to investigate the joint effect of occupational exposure to asbestos, and tobacco and alcohol consumption, on the risk of laryngeal cancer among men. Methods We used data from a large population-based case–control study conducted in France. We estimated two-way and three-way interactions between asbestos exposure (never vs ever exposed), tobacco consumption (〈20 vs ≥20 pack-years) and alcohol consumption (〈5 vs ≥5 drinks per day). The interaction on an additive scale was assessed by estimating the relative excess risk due to interaction (RERI) and the attributable proportion due to interaction, and the interaction on a multiplicative scale was assessed by estimating the multiplicative interaction parameter (). Multiplicative interactions were also assessed using fractional polynomials for alcohol drinking, tobacco smoking and asbestos exposure. Results When compared with light-to-moderate smokers and drinkers never exposed to asbestos, the increase in laryngeal cancer risk was smallest among light-to-moderate drinkers and smokers exposed to asbestos (OR=2.23 (1.08 to 4.60)), and highest among heavy smokers and drinkers ever exposed to asbestos (OR=69.39 (35.54 to 135.5)). We found an additive joint effect between asbestos exposure and alcohol consumption (RERI=4.75 (–4.29 to 11.12)), whereas we observed a more than additive joint effect between asbestos exposure and tobacco consumption (RERI=8.50 (0.71 to 23.81)), as well as between asbestos exposure, and tobacco and alcohol consumption (RERI=26.57 (11.52 to 67.88)). However, our results did not suggest any interaction on a multiplicative scale. Conclusions Our results suggest that asbestos exposure, in combination with tobacco and alcohol exposure, accounted for a substantial number of laryngeal cancer cases. Our findings therefore highlight the need for prevention in activities, such as construction work, where exposure to asbestos-containing materials remains.

Description: Objectives Policies have been introduced to reduce sickness absence, but their effectiveness is largely unknown. In a natural experiment, we examined effects of legislative changes on return to work and work participation. Methods The source population consisted of up to 72 164 Finnish public sector employees with a permanent job contract in 2008–2011 (before) and in 2013–2014 (after). We used employees with a continuous sickness absence of at least 30 calendar-days (n=5708–6393), 60 compensated days (n=1481–1655) and 90 compensated days (n=766–932). We examined sustainable return to work (a minimum of 28 consecutive working days) with survival analysis as well as monthly work participation after a sickness absence, and annual gain in work participation after the intervention, using trajectory analyses. Results Sustainable return to work after 60 days of sickness absence occurred earlier after the legislative changes (p value 0.017), although the effect reduced towards the end of the follow-up. There were no differences in return to work after a 30 or 90 days of sickness absence. The largest annual gain, postintervention versus preintervention, in monthly work participation was observed among employees with 60 days of sickness absence and was 230.9 person-years/10 000 employees. The corresponding annual gains among those with 30 days and 90 days of sickness absence were 51.8 and 39.6, respectively. Conclusions Our findings suggest that the legislative changes, obligating early notification of prolonged sickness absences as well as assessment of remaining work ability and possibilities to continue working, may enhance sustainable return to work in the short term. Other measures will be needed to enhance work participation, especially in the long term.

Description: The burden of disabling musculoskeletal pain and injuries (musculoskeletal disorders, MSDs) arising from work-related causes in many workplaces remains substantial. There is little consensus on the most appropriate interventions for MSDs. Our objective was to update a systematic review of workplace-based interventions for preventing and managing upper extremity MSD (UEMSD). We followed a systematic review process developed by the Institute for Work & Health and an adapted best evidence synthesis. 6 electronic databases were searched (January 2008 until April 2013 inclusive) yielding 9909 non-duplicate references. 26 high-quality and medium-quality studies relevant to our research question were combined with 35 from the original review to synthesise the evidence on 30 different intervention categories. There was strong evidence for one intervention category, resistance training, leading to the recommendation: Implementing a workplace-based resistance training exercise programme can help prevent and manage UEMSD and symptoms . The synthesis also revealed moderate evidence for stretching programmes, mouse use feedback and forearm supports in preventing UEMSD or symptoms. There was also moderate evidence for no benefit for EMG biofeedback, job stress management training, and office workstation adjustment for UEMSD and symptoms. Messages are proposed for both these and other intervention categories.

Description: The aim of this study was to estimate the prevalence of viral hepatitis C (HCV) infection among healthcare workers (HCWs) compared to the general population. A systematic search for the years 1989–2014 was conducted in the Medline, Embase and Cochrane databases. Studies on hepatitis C in HCWs were included if they incorporated either a control group or reference data for the general population. The study quality was classified as high, moderate or low. Pooled effect estimates were calculated to determine the odds of occupational infection. Heterogeneity between studies was analysed using the 2 test (p〈0.10) and quantified using the I 2 test. 57 studies met our criteria for inclusion and 44 were included in the meta-analysis. Analysis of high and moderate quality studies showed a significantly increased OR for HCV infection in HCWs relative to control populations, with a value of 1.6 (95% CI 1.03 to 2.42). Stratification by study region gave an OR of 2.1 in low prevalence countries; while stratification by occupational groups gave an increased prevalence for medical (OR 2.2) and for laboratory staff (OR 2.2). The OR for professionals at high risk of blood contact was 2.7. The pooled analysis indicates that the prevalence of infection is significantly higher in HCWs than in the general population. The highest prevalence was observed among medical and laboratory staff. Prospective studies that focus on HCW-specific activity and personal risk factors for HCV infection are needed.

Description: Objective The aim of our study was to estimate the incidence of digestive cancers within a cohort of asbestos-exposed workers. Methods Our study was based on a cohort of 2024 participants occupationally exposed to asbestos. The incidence of digestive cancers was calculated from 1 January 1978 to 31 December 2009 and compared with levels among the local general population using Standardised Incidence Ratios (SIRs). Asbestos exposure was assessed using the company’s job-exposure matrix. Results 119 cases of digestive cancer were observed within our cohort, for an expected number of 77 (SIR=1.54 (1.28 to 1.85)). A significantly elevated incidence was observed for peritoneal mesothelioma, particularly in women. Significantly elevated incidences were also observed among men for: all digestive cancers, even when excluding peritoneal mesothelioma (SIR=1.50 (1.23 to 1.82)), oesophageal cancer (SIR=1.67 (1.08 to 2.47)) and liver cancer (SIR=1.85 (1.09 to 2.92)). Concerning colorectal cancer, a significant excess of risk was observed for men with exposure duration above 25 years (SIR=1.75 (1.05 to 2.73)). Conclusions Our results are in favour of a link between long-duration asbestos exposure and colorectal cancer in men. They also suggest a relationship between asbestos exposure and cancer of the oesophagus in men. Finally, our results suggest a possible association with small intestine and liver cancers in men.

Description: Objectives Non-communicable diseases (NCDs) constitute an increasing slice of the global burden of disease, with the South-East Asia region projected to see the highest increase in NCD-related deaths over the next decade. Mining industry employees may be exposed to various factors potentially elevating their NCD risk. This study aimed to assess the distribution and 5-year longitudinal trends of key metabolic NCD risk factors in a cohort of copper–gold mining company workers in Papua, Indonesia. Methods Metabolic indicators of NCD risk were assessed among employees (15 580 at baseline, 6496 prospectively) of a large copper–gold mining operation in Papua, Indonesia, using routinely collected 5-year medical surveillance data. The study cohort comprised individuals aged 18–68 years employed for ≥1 year during 2008–2013. Assessed risk factors were based on repeat measures of cholesterol, blood glucose, blood pressure and body weight, using WHO criteria. Results Metabolic risk indicator rates were markedly high and increased significantly from baseline through 5-year follow-up (p〈0.001). Adjusting for gender and age, longer duration of employment (≥10 years) predicted raised cholesterol (adjusted OR (AOR)=1.13, p=0.003), raised blood pressure (AOR=1.16, p=0.009) and overweight/obesity (AOR=1.14, p=0.001) at baseline; and persistent raised cholesterol (AOR=1.26, p=0.003), and both incident (AOR=1.33, p=0.014) and persistent raised blood glucose (AOR=1.62, p=0.044) at 3-year follow-up. Conclusions Individuals employed for longer periods in a mining operations setting in Papua, Indonesia, may face elevated NCD risk through various routes. Workplace health promotion interventions and policies targeting modifiable lifestyle patterns and environmental exposures present an important opportunity to reduce such susceptibilities and mitigate associated health risks.

Description: Objectives Common mental disorders (CMDs) are a major cause of rising disability benefit expenditures. We urgently need evidence on programmes that can increase work participation in CMDs. The aim of this study was to evaluate the effectiveness of work-focused cognitive–behavioural therapy (CBT) and individual job support for people struggling with work participation due to CMDs. Methods A randomised controlled multicentre trial (RCT) including 1193 participants was conducted. Participants were on sick leave, at risk of going on sick leave or on long-term benefits. The intervention integrated work-focused CBT with individual job support. The control group received usual care. The main outcome was objectively ascertained work participation at 12 months follow-up, with changes in mental health and health-related quality of life as secondary outcomes. Results A larger proportion of participants in the intervention group had increased or maintained their work participation at follow-up compared to the control group (44.2% vs 37.2%, p=0.015). The difference remained significant after 18 months (difference 7.8%, p=0.018), and was even stronger for those on long-term benefits (difference 12.2%, p=0.007). The intervention also reduced depression (t=3.23, p≤0.001) and anxiety symptoms (t=2.52, p=0.012) and increased health-related quality of life (t=2.24, p=0.026) more than usual care. Conclusions A work-focused CBT and individual job support was more effective than usual care in increasing or maintaining work participation for people with CMDs. The effects were profound for people on long-term benefits. This is the first large-scale RCT to demonstrate an effect of a behavioural intervention on work participation for the large group of workers with CMDs. Trial registration number ClinicalTrials.gov, registration number: NCT01146730.

Description: Objective To examine the association between employment duration, elongate mineral particle (EMP) exposure, silica exposure and the risk of lung cancer in the taconite mining industry. Methods We conducted a nested case–control study of lung cancer within a cohort of Minnesota taconite iron mining workers employed by any of the mining companies in operation in 1983. Lung cancer cases were identified by vital records and cancer registry data through 2010. Two age-matched controls were selected from risk sets of cohort members alive and lung cancer free at the time of case diagnosis. Calendar time-specific exposure estimates were made for every job and were used to estimate workers’ cumulative exposures. ORs and 95% CIs were estimated using conditional logistic regression. We evaluated total lung cancer risk and risk of histological subtype by total work duration and by cumulative EMP, and silica exposure by quartile of the exposure distribution. Results A total of 1706 cases and 3381 controls were included in the analysis. After adjusting for work in haematite mining, asbestos exposure and sex, the OR for total duration of employment was 0.99 (95% CI 0.96 to 1.01). The ORs for quartile 4 versus 1 of EMP and silica exposure were 0.82 (95% CI 0.57 to 1.19) and 0.97 (95% CI 0.70 to 1.35), respectively. The risk of each histological subtype of lung cancer did not change with increasing exposure. Conclusions This study suggests that the estimated taconite mining exposures do not increase the risk of developing lung cancer.

Description: We welcome the opportunity to respond to Goodman et al , 1 and to correct their misperceptions about our paper. 2 As noted in their letter, Kerper et al 3 also recently analysed lung function decrements associated with pleural plaques. While the methodological details of our publications differed somewhat, the identified literature and the conclusions regarding magnitude of effect on lung function were well aligned. We found statistically significant 2–4% decrements in lung function in people exposed to asbestos with pleural plaques relative to asbestos-exposed people without abnormalities. Kerper et al 3 reported 3–5% decrements. It is not clear why Kerper et al 3 chose to ignore differences in study size: all studies were considered equally in their analysis, despite sample sizes ranging from tens to thousands, and a summary estimate was not calculated. With respect to the specific points raised, 1 although we...

Description: Objectives To conduct a systematic review of changes in lung function in relation to presence of pleural plaques in asbestos-exposed populations. Methods Database searches of PubMed and Web of Science were supplemented by review of papers’ reference lists and journals’ tables of contents. Methodological features (eg, consideration of potential confounding by smoking) of identified articles were reviewed by ≥two reviewers. Meta-analyses of 20 studies estimated a summary effect of the decrements in per cent predicted (%pred) forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV 1 ) associated with presence of pleural plaques. Results Among asbestos-exposed workers, the presence of pleural plaques was associated with statistically significant decrements in FVC (4.09%pred, 95% CI 2.31 to 5.86) and FEV 1 (1.99%pred, 95% CI 0.22 to 3.77). Effects of similar magnitude were seen when stratifying by imaging type (X-ray or high-resolution CT) and when excluding studies with potential methodological limitations. Undetected asbestosis was considered as an unlikely explanation of the observed decrements. Several studies provided evidence of an association between size of pleural plaques and degree of pulmonary decrease, and presence of pleural plaques and increased rate or degree of pulmonary impairment. Conclusions The presence of pleural plaques is associated with a small, but statistically significant mean difference in FVC and FEV 1 in comparison to asbestos-exposed individuals without plaques or other abnormalities. From a public health perspective, small group mean decrements in lung function coupled with an increased rate of decline in lung function of the exposed population may be consequential.