Bayesian identification and estimation of radon-related increased hazard rates of cancer death in the updated French cohort of uranium miners (1946-2014).

OBJECTIVE: A recent update of the French cohort of uranium miners added seven years of follow-up data. We use these new data to look for new possible radon-related increased risks and refine the estimation of the potential association between cumulative radon exposure and four cancer sites: lung cancer, kidney cancer, brain and central nervous system (CNS) cancer and leukemia (excluding chronic lymphocytic leukemia, which is not radiation-induced). METHODS: Several parametric survival models are proposed, fitted and compared under the Bayesian paradigm, to perform new and original exposure-risk analyses. In line with recent UNSCEAR recommendations, we consider time-related effect modifiers and exposure rate as potential effect modifying factors. We use Bayesian model selection criteria to identify radon-related increased hazard rates. RESULTS: Under the assumption of a linear exposure-risk relationship, we found a substantial evidence for a strictly positive effect of cumulative radon exposure on the hazard rate of death by lung cancer among French uranium miners. Given the current available data under the assumptions of a linear or log-linear exposure-risk relationship, it is not possible to conclude in favour of the absence or the existence of a strictly positive effect of chronic exposure to radon on the hazard rate of death by kidney cancer. Regarding death by brain and CNS cancer, there is a substantial evidence for the absence of radon-related effect. Finally, under the assumption of a log-linear exposure-risk relationship, a small positive radon-related effect appears when looking at the risk of death by leukemia (excluding CLL). CONCLUSION: This study investigates the existence of radon-related increased risk of death by lung cancer, kidney cancer, brain and CNS cancer and leukemia under a Bayesian framework and assumptions of linear and log-linear exposure-risk relationships. If there is no doubt in the interpretation of the results for lung cancer and brain and CNS cancer, the conclusion is less clear-cut in the case of kidney cancer and leukemia (excluding CLL). A future update of the French cohort, increasing the follow-up time for miners, may help to reach a clearer conclusion for these two cancer sites.

Disparities in job characteristics by race and sex in a Southern aluminum smelting facility.

BACKGROUND: Former workers at a Southern aluminum smelting facility raised concerns that the most hazardous jobs were assigned to Black workers, but the role of workplace segregation had not been quantified or examined in the company town. Prior studies discuss race and gender disparities in working conditions, but few have documented them in the aluminum industry. METHODS: We obtained workers' company records for 1985-2007 and characterized four job metrics: prestige (sociologic rankings), worker-defined danger (worker assessments), annual wage (1985 dollars), and estimated total particulate matter (TPM) exposure (job exposure matrix). Characteristics of job at hire and trajectories were compared by race and sex using linear binomial models. RESULTS: Non-White males had the highest percentage of workers in low prestige and high danger jobs at hire and up to 20 years after. After 20 years tenure, 100% of White workers were in higher prestige and lower danger jobs. Most female workers, regardless of race, entered and remained in low-wage jobs, while 50% of all male workers maintained their initial higher-wage jobs. Non-White females had the highest prevalence of workers in low-wage jobs at hire and after 20 years-increasing from 63% (95% CI: 59-67) to 100% (95% CI: 78-100). All female workers were less likely to be in high TPM exposure jobs. Non-White males were most likely to be hired into high TPM exposure jobs, and this exposure prevalence increased as time accrued, while staying constant for other race-sex groups. CONCLUSIONS: There is evidence of job segregation by race and sex in this cohort of aluminum smelting workers. Documentation of disparities in occupational hazards is important for informing health interventions and research.

Recurrent pain and work disability: a record linkage study.

PURPOSE: We examined the associations between recurrent single- and multisite pain and incident sickness absence (SA) of different lengths and the risk of disability pension (DP). METHODS: The data were derived from the Finnish Helsinki Health Study. Pain measures were recorded for panel 1 in 2000/2 and 2007, and for panel 2 in 2007 and 2012 (altogether 3191 employees). SA data were obtained from the employer's personnel register and DP events from the Finnish Centre for Pensions. Negative binomial regression models with generalized estimation equations were used to model the incidence of self-certified short- (1-3 days), and medically certified medium- (4-14 days) and long-term (more than 14 days) SA episodes. Cox regression models were fitted for the associations between pain and all-cause DP and competing risk models for DP by diagnostic groups. Social and health-related covariates were adjusted for. RESULTS: Recurrent pain was associated with short-, medium- and long-term SA. Additionally, recurrent single- and multisite pain increased the risk of long-term SA. Recurrent single or multisite pain was further associated with an increased risk of DP, while a single instance of pain did not increase the risk. CONCLUSIONS: These results suggest that recurrent pain is a robust determinant of subsequent SA and DP risk. Improved understanding of determinants of recurrent pain is needed to inform the development of targeted measures to reduce SA and premature exit from employment.

Cancer and noncancer mortality among aluminum smelting workers in Badin, North Carolina.

BACKGROUND: Badin, North Carolina, hosted an aluminum smelting plant from 1917 to 2007. The Concerned Citizens of West Badin reported suspected excess cancer mortality among former employees. This study aimed to investigate these concerns. METHODS: The study cohort was enumerated from United Steel Workers' records of workers employed from 1980 to 2007. Cause-specific mortality rates in the cohort were compared with North Carolina population mortality rates using standardized mortality ratios (SMRs), standardized by age, sex, race, and calendar period. We estimated cause-specific adjusted standardized mortality ratios (aSMRs) using negative controls to mitigate healthy worker survivor bias (HWSB). Standardized rate ratios (SRRs) were calculated to compare mortality rates between workers ever employed vs never employed in the pot room. RESULTS: All-cause mortality among Badin workers was lower than in the general population (SMR: 0.81, 95% confidence interval [CI]: 0.71-0.92). After adjusting for HWSB, excesses for all cancers (aSMR: 1.55, 95% CI: 1.10-2.21), bladder cancer (3.47, 95% CI: 1.25-9.62), mesothelioma (17.33, 95% CI: 5.40-55.59), and respiratory cancer (1.24, 95% CI: 0.77-1.99) were observed. Black males worked the highest proportion of their employed years in the pot room. Potroom workers experienced higher respiratory cancer (SRR: 2.99, 95% CI: 1.23-7.26), bladder cancer (SRR: 1.58, 95% CI: 0.15-15.28), and mesothelioma (SRR: 3.36, 95% CI: 0.21-53.78) mortality rates than never workers in the pot room. CONCLUSIONS: This study responds to concerns of a group of former aluminum workers. The results, while imprecise, suggest excess respiratory and bladder cancers among pot room workers in a contemporary cohort of union employees at a US smelter.

Increased overall and cause-specific mortality associated with disability among workers' compensation claimants with low back injuries.

BACKGROUND: Mortality tends to be higher among people who do not work than among workers, but the impact of work-related disability on mortality has not been well studied. METHODS: The vital status through 2015 was ascertained for 14 219 workers with an accepted workers' compensation claim in West Virginia for a low back injury in 1998 or 1999. Mortality among the cohort compared with the West Virginia general population was assessed using standard life table techniques. Associations of mortality and disability-related factors within the cohort were evaluated using Cox proportional hazards regression. RESULTS: Compared to the general population, mortality from accidental poisoning was significantly elevated among the overall cohort and lost-time claimants. Most deaths from accidental poisoning in the cohort were due to drug overdoses involving opioids. Mortality from intentional self-harm was also significantly elevated among lost-time claimants. In internal analyses, overall mortality and mortality from cancer, heart disease, intentional self-harm, and drug overdoses involving opioids was significantly associated with lost time. Overall mortality and mortality from drug overdoses involving opioids were also significantly associated with amount of lost time, permanent partial disability, and percent permanent disability. Heart disease mortality was also significantly associated with the amount of lost time. CONCLUSIONS: The results suggest that disability itself may impact mortality risks. If confirmed, these results reinforce the importance of return to work and other efforts to reduce disability.

Occupational cohort study of asbestos-cement workers in a contaminated site in Sicily (Italy).

OBJECTIVES: to analyse the asbestos-related diseases risk among the former workers of Sacelit asbestos-cement plant, operating in San Filippo del Mela (Sicily: 1958- 1993). DESIGN: cohort study. SETTING AND PARTICIPANTS: 228 subjects were employed in Sacelit from 1958 to 1993. Due to the available observation periods, the analyses of the different outcomes were performed for the subjects alive at the beginning of the respective follow up periods: mortality (1986-2018) was analysed for 204 subjects (177 men, 27 women), hospitalization (2001-2016) for 164 workers (139 men, 25 women) and the incidence of mesothelioma (1998-2016) was estimated for 178 subjects (153 men, 25 women). MAIN OUTCOMES MEASURES: mortality (Standardized Mortality Ratio: SMR) and hospitalization (Standardized Hospitalization Ratio: SHR) from specific diseases were analysed. Incidence (Standardized Incidence Ratio: SIR) of mesothelioma cases was detected, also. SMR (1986-2014), SHR (2001-2016) and SIR (1998-2016), with 95% Confidence Intervals, were computed with respect to the regional rates, with STATA11. RESULTS: in the men cohort, mortality from lung (17 cases, SMR 2.83) and pleural cancers (5 cases, SMR 30) and from asbestosis (15 cases, SMR 1,930) was in excess. The risk of hospitalization was in excess, in both genders, from lung cancer (men: 6 cases, SHR 4.1; women: 2 cases, SHR 8.6) and asbestosis (men: 17 cases, SHR 1,304; women: 6 cases, SHR 2,455). The incidence of mesothelioma was in excess in men (5 cases, SIR 23.9); no female cases of mesothelioma were observed. CONCLUSIONS: a high occurrence of asbestos-related diseases in the cohort, particularly among men, was observed. The excess of hospitalization from asbestosis and lung cancer was highlighted also in women. The prosecution of the on-going health surveillance plan is particularly appropriated.

Extended Mortality Follow-up of a Cohort of 25,460 Workers Exposed to Acrylonitrile.

We extended the mortality follow-up of a cohort of 25,460 workers employed at 8 acrylonitrile (AN)-producing facilities in the United States by 21 years. Using 8,124 deaths and 1,023,922 person-years of follow-up, we evaluated the relationship between occupational AN exposure and death. Standardized mortality ratios (SMRs) based on deaths through December 31, 2011, were calculated. Work histories and monitoring data were used to develop quantitative estimates of AN exposure. Hazard ratios were estimated by Cox proportional hazards regression. All-cause mortality and death from total cancer were less than expected compared with the US population. We observed an excess of death due to mesothelioma (SMR = 2.24, 95% confidence interval (CI): 1.39, 3.42); no other SMRs were elevated overall. Cox regression analyses revealed an elevated risk of lung and bronchial cancer (n = 808 deaths; for >12.1 ppm-year vs. unexposed, hazard ratio (HR) = 1.43, 95% CI: 1.13, 1.81; P for trend = 0.05), lagged 10 years, that was robust in sensitivity analyses adjusted for smoking and co-exposures including asbestos. Death resulting from bladder cancer (for >2.56 ppm vs. unexposed, lagged 10-year HR = 2.96, 95% CI: 1.38, 6.34; P for trend = 0.02) and pneumonitis (for >3.12 ppm-year vs. unexposed, HR = 4.73, 95% CI: 1.42, 15.76; P for trend = 0.007) was also associated with AN exposure. We provide additional evidence of an association between AN exposure and lung cancer, as well as possible increased risk for death due to bladder cancer and pneumonitis.

Employment characteristics and cause-specific mortality at automotive electronics manufacturing plants in Huntsville, Alabama.

BACKGROUND: This study was carried out in response to worker concerns over their exposure to lead solder and chlorinated solvents at automotive electronics manufacturing plants in Huntsville, Alabama. METHODS: A study of 4396 United Autoworkers members ever-employed at the plants between 1972 and 1993 was conducted with mortality follow-up through 2016. Poisson regression was used to estimate mortality rate ratios (RR) according to employment characteristics, including calendar period of employment. RESULTS: Pre-1977 hires exhibited elevated adjusted rates of all-cause (RR, 1.29; 95% confidence interval [CI], 1.09-1.52), cardiovascular (RR, 1.38; 95% CI, 1.03-1.86), and digestive system (RR, 2.31; 95% CI, 1.04-5.10) disease mortality relative to the most recent hire group (1984-1993). Never- versus ever-employment in a skilled trade job was associated with elevated adjusted rates of all-cause, all-cancer, and cardiovascular disease mortality. Nervous system disorder mortality was greatest among 1977-1983 hires. CONCLUSIONS: Elevated mortality among pre-1977 hires is consistent with worker concerns over greater exposure to hazards at the original plant building.

Mortality among autoworkers manufacturing electronics in Huntsville, Alabama.

BACKGROUND: Workers raised concerns over suspected excesses of mortality at automotive electronics manufacturing facilities in Huntsville, Alabama. METHODS: A study of 4396 UAW members ever-employed at Huntsville facilities between 1972 and 1993 was conducted with mortality follow-up through 2016. Standardized Mortality Ratios (SMRs) were estimated using U.S. and Alabama reference rates. RESULTS: Relative to U.S. rates, there was a modest excess of all-cause mortality among White female workers (SMR 1.08, 95%CI: 0.99-1.18) and among all workers hired <1977 at the original plant building (SMR 1.10, 95%CI: 0.99-1.22). There was excess nervous system disorder (SMR 1.24, 95%CI: 0.91-1.65) and brain and nervous system cancer (SMR 1.31, 95%CI: 0.67-2.28) mortality. Estimates for several causes of interest were imprecise. CONCLUSIONS: All-cause mortality estimates were greater than anticipated based on results from other UAW cohorts. The excess of nervous system disease mortality is consistent with other studies of electronics workers exposed to lead-solder and chlorinated solvents.

Recurrent back pain during working life and exit from paid employment: a 28-year follow-up of the Whitehall II Study.

OBJECTIVES: To examine the impact of recurrent, as compared with single, reports of back pain on exit from paid employment over decades of follow-up. METHODS: The study sample was from the British Whitehall II Study cohort (n=8665, 69% men, aged 35-55 at baseline), who had provided information about their reports of back pain between 1985 and 1994. Data about exit from paid employment (health-related and non-health related exit, unemployment and other exit) were collected between 1995 and 2013. Repeated measures logistic regression models were fitted to examine the associations, and adjust for covariates. RESULTS: Recurrent pain was reported by 18% of participants, while 26% reported pain on an occasion and 56% did not report pain. Report of back pain on an occasion was not associated with health-related job exit, whereas recurrent pain was associated with such an exit (OR 1.51; 95% CI 1.15 to 1.99), when compared with those who did not report pain. These associations were somewhat stronger among middle-grade and lower-grade employees, while these associations were not seen among higher-grade employees. Differences in associations by age and psychosocial working conditions were small. CONCLUSIONS: These results highlight the need for early detection of recurrent back pain to prevent exit out of paid employment for health reasons. As the risk varies by occupational grade, this emphasises the importance of identification of high-risk groups and finding ways to address their modifiable risk factors.

Estimation of TETRA radio use in the Airwave Health Monitoring Study of the British police forces.

BACKGROUND: The Airwave Health Monitoring Study aims to investigate the possible long-term health effects of Terrestrial Trunked Radio (TETRA) use among the police forces in Great Britain. Here, we investigate whether objective data from the network operator could be used to correct for misreporting in self-reported data and expand the radio usage availability in our cohort. METHODS: We estimated average monthly usage of personal radio in the 12 months prior to enrolment from a missing value imputation model and evaluated its performance against objective and self-reported data. Factors associated with TETRA radio usage variables were investigated using Chi-square tests and analysis of variance. RESULTS: The imputed data were better correlated with objective than self-reported usage (Spearman correlation coefficient = 0.72 vs. 0. 52 and kappa 0.56 [95% confidence interval 0.55, 0.56] vs. 0.46 [0.45, 0.47]), although the imputation model tended to under-estimate use for higher users. Participants with higher personal radio usage were more likely to be younger, men vs. women and officer vs. staff. The median average monthly usage level for the entire cohort was estimated to be 29.3 min (95% CI: [7.2, 66.6]). CONCLUSION: The availability of objective personal radio records for a large proportion of users allowed us to develop a robust imputation model and hence obtain personal radio usage estimates for ~50,000 participants. This substantially reduced exposure misclassification compared to using self-reported data and will allow us to carry out analyses of TETRA usage for the entire cohort in future work.

Acute Exposure to Terrestrial Trunked Radio (TETRA) has effects on the electroencephalogram and electrocardiogram, consistent with vagal nerve stimulation.

BACKGROUND: Terrestrial Trunked Radio (TETRA) is a telecommunications system widely used by police and emergency services around the world. The Stewart Report on mobile telephony and health raised questions about possible health effects associated with TETRA signals. This study investigates possible effects of TETRA signals on the electroencephalogram and electrocardiogram in human volunteers. METHODS: Blinded randomized provocation study with a standardized TETRA signal or sham exposure. In the first of two experiments, police officers had a TETRA set placed first against the left temple and then the upper-left quadrant of the chest and the electroencephalogram was recorded during rest and active cognitive processing. In the second experiment, volunteers were subject to chest exposure of TETRA whilst their electroencephalogram and heart rate variability derived from the electrocardiogram were recorded. RESULTS: In the first experiment, we found that exposure to TETRA had consistent neurophysiological effects on the electroencephalogram, but only during chest exposure, in a pattern suggestive of vagal nerve stimulation. In the second experiment, we observed changes in heart rate variability during exposure to TETRA but the electroencephalogram effects were not replicated. CONCLUSIONS: Observed effects of exposure to TETRA signals on the electroencephalogram (first experiment) and electrocardiogram are consistent with vagal nerve stimulation in the chest by TETRA. However given the small effect on heart rate variability and the lack of consistency on the electroencephalogram, it seems unlikely that this will have a significant impact on health. Long-term monitoring of the health of the police force in relation to TETRA use is on-going.

Validation of objective records and misreporting of personal radio use in a cohort of British Police forces (the Airwave Health Monitoring Study).

BACKGROUND: Terrestrial Trunked Radio (TETRA) is a digital communication system progressively adopted by Police Forces in Great Britain since 2001. In 2000, the UK Independent Expert Group on Mobile Phones suggested that exposure to TETRA-like signal modulation might have adverse effects on health. The Airwave Health Monitoring Study was established to investigate possible long-term effects of TETRA use on health. This requires estimation of TETRA use among Police Force employees participating in the study. METHODS: We investigated TETRA usage among 42,112 Police officers and staff. An algorithm was created to link each personal radio user to his/her objective radio usage records for the 26,035 participants with available data. We linked 16,577 personal radio users to their objective radio usage records and compared self-reported usage with data from the TETRA operator for those individuals. RESULTS: For weekly usage, the correlation between self-reported and operator-derived personal radio usage was r=0.69 for number and r=0.59 for the duration of calls. Compared with objective data, participants under-reported the number of calls and over-reported the duration of calls by a factor of around 4 and 1.6 respectively. Correlations were lower and bias higher when looking at daily usage. CONCLUSION: Where both objective and self-reported information were available, our study showed substantial misreporting in self-reported TETRA usage. Successful linkage of large numbers of TETRA users to objective data on their personal radios will allow objective assessment of TETRA radio usage for these participants and development of algorithms to correct bias in self-reported data for the remainder.

Country specific associations between social contact and mental health: evidence from civil servant studies across Great Britain, Japan and Finland.

OBJECTIVES: Little is known about which component, such as social contact of social networks is associated with mental health or whether such an association can be observed across countries. This study examined whether the association between frequent social contact and mental health differs by composition (relatives or friends) and whether the associations are similar across three occupational cohorts from Great Britain, Japan, and Finland. STUDY DESIGN: Cross-sectional analysis of data from three prospective cohort studies. METHODS: Participants were civil servants of a prospective cohort study based in London (Men: n = 4519; Women: n = 1756), in the West Coast of Japan (Men: n = 2571; Women: n = 1102), and in Helsinki, Finland (Men: n = 1181; Women: n = 5633); we included the information on study variables which is complete. Mental health function was the study outcome, indicated by the total score from the Mental Health Component on the Short Form Health Survey36. Participants reported frequencies of contacts with their relatives or friends via a questionnaire. Age, marital status, and occupational position were treated as confounders in this study. RESULTS: Findings from multiple regression showed that the associations between social contact and mental health function were different depending on country of origin and gender. Among British or Japanese men, frequent contact with both friends and relatives was positively associated with their mental health function, while only social contact with friends was significantly associated with mental health of Finnish men. In women, the patterns of the associations between social contact and mental health were more distinctive: friends for Great Britain, relatives for Japan, and friends and relatives for Finland. These significant associations were independent of the confounders. CONCLUSIONS: Social contact was related to mental health of working people; however, culture and gender are likely to be tapped into.

Cancer incidence among 41,000 offshore oil industry workers.

BACKGROUND: Cancer incidence among Norwegian offshore oil industry workers has been studied in two equally sized cohorts of 28000 workers, in a survey-based cohort study followed 1999-2005 and a register-based cohort study followed 1981-2003. AIMS: To determine the overall cancer incidence in both cohorts merged, with an extended follow-up. METHODS: The merged cohort yielded 41,140 individuals followed for cancer diagnoses 1999-2009. Standardized incidence ratios (SIRs) with 95% confidence intervals (CIs) were computed by gender and by period of first employment using cancer registry data. RESULTS: Among female workers, the total number of cancers was slightly higher than expected (SIR 1.17, 95% CI 1.02-1.34), and excesses of acute myeloid leukaemia (AML) (SIR 5.29, 95% CI 1.72-12), malignant melanoma (SIR 2.13, 95% CI 1.41-3.08) and lung cancer (SIR 1.69, 95% CI 1.03-2.61) were observed. Among male workers, the total number of cancer cases was close to that expected (SIR 1.03, 95% CI 0.99-1.08), but cases of pleural cancer (SIR 2.56, 95% CI 1.58-3.91) and bladder cancer (SIR 1.25, 95% CI 1.05-1.49) were higher than expected. Among male workers first employed before 1986, the numbers of observed cancer cases were higher than expected for most sites, while this was not evident among those employed later. CONCLUSIONS: Further studies with exposure data and confounder control are needed to address whether the observed excesses of pleural cancer and AML can be attributed to offshore work.

Evaluating exposure-response relationship in 1,3-butadiene and leukemia studies.

OBJECTIVES: 1,3-Butadiene (BD) exposure's link to leukemia is under regulatory scrutiny. The assessment methods for BD exposure risks have evolved from early animal and limited human studies to advanced exposure-response modelling with comprehensive quantitative data. The objec- tive of this study is to explore the nuances of exposure-response modelling, investigating how various statistical methods have influenced the quan- tification of exposure-response relationships. MATERIAL AND METHODS: Although this study was not conducted as a formal systematic review, a search was performed in Medline/Pubmed to identify all human studies on leukemia risk assessment for BD exposure. This search included articles written in English. The electronic search spanned from inception of records until July 23, 2023, using the search term: "butadiene AND (leukaemia OR leukemia OR myeloid OR lymphoid)" and was restricted to human species. Focusing on the synthetic styrene-butadiene rubber (SBR) industry cohort study conducted by the University of Alabama at Birmingham, USA, this review evaluates various statistical models and factors influenc- ing exposure-response modelling. RESULTS: Peak exposures to BD may be more influential in the dose-response relationship than cumulative or long-term exposure. The authors recommend utilizing ß-coefficients derived from the latest SBR study update, employing Cox proportional hazard modelling, non-lagged and non-transformed cumulative BD exposure, and adjusting for age and peak BD exposure. The study reveals that statistical model selection has a limited impact on the calculated dose-response effects. The significant variation in estimated cancer mortality values arises from additional assumptions needed for metrics like the excess leukemia risk or the occupational BD effective concentration. CONCLUSIONS: In con- clusion, this study provides insights into exposure-response modelling for BD exposure and leukemia mortality, highlighting the importance of peak exposures. The recommended statistical approach offers a reliable basis for regulatory risk assessment and public health population metrics. Int J Occup Med Environ Health. 2024;37(3):300-10.

Study profile: protocol outline and study perspectives of the cohort by the National Institute of Occupational Safety and Health, Japan (JNIOSH cohort).

How work burden affects physical and mental health has already been studied extensively; however, many issues have remained unexamined. In 2017, we commenced a prospective cohort study of workers at companies in Japan, with a follow-up period of 5-10 years, in order to investigate the current situation of overwork-related health outcomes. From 2017 to 2020, a target population of 150,000 workers across 8 companies was identified. Of these, almost 40,000 workers agreed to participate in the baseline survey. Data on working hours, medical check-up measurements, occupational stress levels, and lifestyle habits were collected. The average age of the participants at baseline was 39.2 ± 11.7 years; 73.1% were men, and 87.7% were regular employees. The most common working hours by self-reported was 41-50 hours per week during normal season, and it increased to more than 50 hours during busy season. Furthermore, more than half of the participants reportedly experienced a form of sleep problem, and the percentage of those who experienced nonrestorative sleep was particularly high.

Sleep Satisfaction May Modify the Association between Metabolic Syndrome and BMI, Respectively, and Occupational Stress in Japanese Office Workers.

The association between obesity and psychological stress is ambiguous. The aim is to investigate the association between metabolic syndrome (MetS) and body mass index (BMI), respectively, with occupational stress among Japanese office workers. The study is a secondary analysis of the intervention group from a randomized controlled trial. There are 167 participants included in the analysis. Occupational stress is self-reported using the Brief Job Stress Questionnaire (BJSQ). BMI and the classification of MetS/pre-MetS was based on the participants' annual health check-up data. The primary exposure is divided into three groups: no MetS, pre-MetS, and MetS in accordance with Japanese guidelines. The secondary exposure, BMI, remains as a continuous variable. Multiple linear regression is implemented. Sensitivity analyses are stratified by sleep satisfaction. Pre-MetS is significantly associated with occupational stress (7.84 points; 95% CI: 0.17, 15.51). Among participants with low sleep satisfaction, pre-MetS (14.09 points; 95% CI: 1.71, 26.48), MetS (14.72 points; 95% CI: 0.93, 28.51), and BMI (2.54 points; 95% CI: 0.05, 4.99) are all significantly associated with occupational stress. No significant associations are observed in participants with high sleep satisfaction. The findings of this study indicate that sleep satisfaction may modify the association between MetS and BMI, respectively, and occupational stress.

Associations of work-related stress and total sleep time with cholesterol levels in an occupational cohort of Japanese office workers.

OBJECTIVE: The aim of the study was to investigate the associations of total sleep time (TST) and occupational stress based on the Brief Job Stress Questionnaire (BJSQ) with cholesterol levels in an occupational cohort of Japanese office workers. METHODS: The present study is a secondary analysis of a subset of participants from a randomized controlled trial. Participants were 179 employees from 5 companies in Tokyo who participated as the intervention group in a 3-month lifestyle intervention study among office workers with metabolic syndrome or at risk of metabolic syndrome. All intervention-group participants used a mobile app and a wearable device. The final population for analysis in the present study were 173 participants. Cholesterol measures were derived from participants' annual health check-up data in the fiscal year preceding their inclusion in the study. Multiple linear regression models were used to determine the association between exposures and outcome. RESULTS: Overall, stress levels were significantly and inversely associated with LDL-C (-7.12 mg/dl; 95% CI: -11.78, -2.45) and LDL-C/HDL-C ratio (-0.16 mg/dl; 95% CI: -0.27, -0.04) per standard deviation increase. Compared to average TST 5.9-7.2 hours, average TST of 4.0-5.3 hours (-4.82 mg/dl; 95% CI: -9.22, -0.43) was inversely associated with HDL-C. CONCLUSION: Incremental increases of stress were significantly and inversely associated with LDL-C and LDL-C/HDL-C ratio. The shortest average TST was inversely associated with HDL-C. The results should be interpreted with care given certain methodological limitations.

A cohort study of banana plantation workers in the French West Indies: first mortality analysis (2000-2015).

Chlordecone, an organochlorine insecticide, was widely used in the French West Indies banana plantations. We set up a cohort of banana plantation workers who worked between 1973 and 1993, the period of authorized use of chlordecone. Vital status and causes of death were collected from French national registries. Workers were followed up from 1 January 2000 to 31 December 2015. Cause-specific mortality in the cohort was compared to that of the general population of the French West Indies by computing standardized mortality ratios (SMRs). A total of 11,112 workers (149,526 person-years, 77% men) were included in the mortality analysis, and 3647 deaths occurred over the study period. There was a slight deficit in all-cause mortality, which was statistically significant in men (SMR = 0.93, 95% CI 0.89-0.96), but not in women (SMR = 0.96, 95% CI 0.89-1.04). All-cancer mortality did not differ significantly from that of the general population (men: SMR = 0.96, 95% CI 0.90-1.03; women: SMR = 1.04, 95% CI 0.89-1.21). Significant excesses of deaths were observed for stomach cancer in women (SMR = 1.94, 95% CI 1.24-2.89) and pancreatic cancer in women farm owners (SMR = 2.31, 95% CI 1.06-4.39). Mortality from prostate cancer was similar to that of the general population in the whole cohort (SMR = 1.00; 95% CI 0.89-1.13) and non-significantly elevated among farm workers (SMR = 1.10, 95% CI 0.87-1.36). Non-significant increases in mortality were also observed for lung cancer in women, leukemia in men, and non-Hodgkin lymphoma in both genders.