UNASSIGNED: We investigated the relationship between occupational lead exposure and amyotrophic lateral sclerosis (ALS) survival in Denmark.
UNASSIGNED: We identified 2,161 ALS cases diagnosed from 1982 to 2013 with at least 5 years of employment history before ALS diagnosis, via the Danish National Patient Registry. Cases were followed until March 2017. We defined lead exposure as never employed in a lead job, ever employed in a lead job, and ever employed in a lead job by exposure probability (<50% vs. ≥50%), excluding jobs held in the 5 years before diagnosis in main analyses. Survival was evaluated using Cox proportional hazards models and stratified by sex and age of diagnosis.
UNASSIGNED: Median age of diagnosis was 63.5 years, and individuals in lead-exposed jobs were diagnosed at a younger age. Adjusted hazard ratios (aHR) were slightly decreased for men ever lead-exposed (aHR:0.92, 95%CI: 0.80, 1.05) and more so among those diagnosed at age 60-69 (lead ≥ 50% aHR: 0.66, 95%CI: 0.45, 0.98), but reversed for men diagnosed at age 70 and later (aHR: 2.03, 95%CI: 1.13, 3.64). No apparent pattern was observed among women.
UNASSIGNED: Occupational lead exposure contributed to shorter survival among men diagnosed at older ages. The inverse associations observed for men diagnosed earlier could relate to possible healthy worker hire effect or health advantages of working in lead-exposed jobs. Our results are consistent with an adverse impact of lead exposure on ALS survival at older ages, with the age at which lead\'s effects on survival worsen later on among those in lead-exposed jobs.

BACKGROUND: Epidemiological studies of occupational risk factors for rare disorders require large study populations with adequate exposure estimates. Job exposure matrices (JEMs) linked to national information on standardized job titles may enable such large studies. We aimed to establish and validate a JEM for occupational hand-wrist exposures that could be linked to Danish national register data on job titles and hand-wrist disorders.
METHODS: We developed a JEM for hand-wrist repetition, force, vibration, and computer work in 96 job groups covering 91% of the 2227 occupational titles in the Danish version of the International Standard Classification of Occupation-88, and examined inter-rater reliability of five expert ratings. Poisson regression models were used to estimate incidence rate ratios for the association of carpal tunnel syndrome (CTS) with the level of repetitive movements, force, vibration, and hours of computer work described by the JEM, adjusted for relevant confounders.
RESULTS: The JEM based on expert ratings had fair to good interrater reliability. The incidence of CTS increased with increasing levels of force, hand-wrist repetition, and vibration, Exposure-response patterns for repetition and vibration became less consistent after adjustment for force. The interaction between repetition and force was complex and did not support an overall positive interaction. Computer work was negatively associated with incident CTS.
CONCLUSIONS: The JEM was able to identify known risk factors for CTS consistent with current evidence, and provided further associations on exposure-response patterns, mutual exposure adjustment, and interaction effects between repetition and force. The reliability of expert assessments of hand-wrist physical exposures was fair to good.

BACKGROUND: Against the backdrop of the debate on extending working life, it is important to identify vulnerable occupational groups by analysing inequalities in healthy life years. The aim of the study is to analyse partial life expectancy (age 30-65) [1] free of musculoskeletal diseases (MSD) and [2] free of cardiovascular diseases (CVD) in occupational groups with different levels of physical and psychosocial exposures.
METHODS: The study is based on German health insurance claims data from 2015 to 2018. The study population comprises all employed insured persons aged 18 to 65 years (N = 1,528,523). Occupational exposures were assessed using a Job Exposure Matrix. Life years free of MSD / CVD and life years with MSD /CVD during working age were estimated using multistate life tables.
RESULTS: We found inequalities in MSD-free and CVD-free life years, with less disease-free years among men and women having jobs with high levels of physical and psychosocial exposures. Men with low physical exposures had 2.4 more MSD-free and 0.7 more CVD-free years than men with high physical exposures. Women with low psychosocial exposures had 1.7 MSD-free and 1.0 CVD-free years more than women with high psychosocial exposures.
CONCLUSIONS: Employees in occupations with high physical and psychosocial demands constitute vulnerable groups for reduced life expectancy free of MSD and CVD. Given the inequalities and high numbers of disease-affected life years during working age, the prevention potential of occupational health care and workplace health promotion should be used more extensively.

OBJECTIVE: Nordic register data are not collected for research purposes, and various dimensions of working conditions are typically missing in register-based research. One way to address the issue of missing information on the work environment in register data is to utilize a job exposure matrix (JEM). The purpose of this paper is to document and provide access to a Mechanical Job Exposure Matrix (JEM) and a validated Occupational Mechanical Job Exposure Index based on the constructed JEM, allowing researchers to utilize the index in register-based research. The JEM and the Occupational Mechanical Job Exposure Index were created using data from five nationwide Surveys of Living Conditions on work environment conducted in Norway in 2006, 2009, 2013, 2016, and 2019, encompassing a total of 43,977 respondents. The index can be merged to register data using occupational codes (STYRK-98) and gender, which is information collected by the registries. The ultimate aim of constructing the index was to create a comprehensive measure of mechanical job exposures for use in future analyses of Norwegian register data.
METHODS: This paper provides the scripts documenting the construction of the Mechanical Job Exposure Matrix (JEM) and the Occupational Mechanical Job Exposure Index, as well as a data file including the matrix and the index. A script for merging the matrix and index to register data is also provided.

Workplace exposures to physical, chemical, and psychosocial factors account for a large burden of chronic diseases. Obtaining useful estimates of current and past workplace exposures is challenging, particularly in large general population studies. Job-exposure matrices (JEMs) are a useful tool for exposure assessment, particularly when no individual level exposure data are available. A JEM provides a cross-tabulation of job titles (sometimes combined with industry) and estimated exposures to workers carrying out these jobs during different time periods. The major limitation of JEMs is that they do not account for individual variation in exposures within the same job. This limitation is offset by the advantages of low cost, wide applicability, lack of bias from self-reporting, and the ability to estimate exposures based on job titles when no other exposure data exist. There is growing use of JEMs in research examining the role of workplace exposures in the development of chronic diseases, and interest in their application to public health practice. This paper provides a scoping review of JEM use, some examples of JEMs, and brief guidance for the application of JEMs in epidemiological research. In conclusion, JEMs provide a useful tool for researchers and public health practitioners to estimate occupational exposures in large scale epidemiological studies relevant to many health conditions.

Certain occupational characteristics have been linked with poor health and reduced longevity. However, the association between occupational characteristics and survival free of disability in a post-retirement age group has not been investigated.
We investigated outcomes in 12,215 healthy older Australian adults in the Aspirin in Reducing Events in the Elderly (ASPREE) and ASPREE Longitudinal Study of Older Persons (ALSOP) sub-study. The ISCO-88 major occupational groups, settings, and activity levels were assigned based on free-text job descriptions. The Finnish Job Exposure Matrix was used to assign occupational characteristics to the three longest-held jobs. The primary endpoint, disability-free survival, was defined as a composite measure of death, dementia, or persistent physical disability. The endpoint of all-cause mortality was analyzed separately. Because of multiple exploratory analyses, only those associations with a two-sided value of p less than 0.005 were considered statistically significant. Cox proportional hazard models were used to calculate adjusted hazard ratios.
Having worked in an \'elementary\' occupation was associated with a reduction in disability-free survival. A specific impact on disability-free survival was observed among those whose work had involved high accident risk and adverse social climate. No significant relationship was identified with those previously exposed to sedentary work, vigorous physical activity, work primarily outdoors, or a range of other occupational characteristics. All-cause mortality was not increased among any of the occupational groups.
This exploratory study found a reduction in disability-free survival among people who worked in \'elementary\' occupations, with specific risks associated with occupations involving high accident risks and adverse social climate.

This study evaluated the hypothesis that higher occupational hand force requirements are related to slower return to work (RTW) after surgery for trapeziometacarpal joint osteoarthritis.
Patients treated surgically for trapeziometacarpal joint osteoarthritis from 2001 to 2017 were identified in the Danish National Patient Register. Sustainable RTW (sRTW) was defined as the first period of 4 consecutive weeks without health-related public transfer payments, according to the Danish National Register on Public Transfer Payments. Occupational codes from the Danish Employment Classification Module were linked to a hand-arm job exposure matrix to obtain occupational hand force requirements for each patient. Cox regression models were used to analyze time until sRTW in relation to hand force requirements with adjustment for age, sex, type of surgery, preoperative sick leave, and calendar year of surgery.
The study included 2,090 patients. Within 104 weeks, 91% sustainably returned to work. The percentage of individuals in the subgroups that did not RTW was 8% of low-force- and medium-force-exposed patients and 14% of high-force-exposed patients. Medium and high occupational hand force requirements were associated with slower sRTW. The adjusted hazard ratio for sRTW was 0.84 (95% confidence interval, 0.74-0.95) for medium and 0.59 (95% confidence interval, 0.50-0.68) for high compared with low hand force requirements. Among patients who returned to work, patients with medium and high hand force requirements had median periods until sRTW of 16 and 18 weeks, respectively, compared with 10 weeks among patients with low hand force requirements.
The prognosis regarding RTW after surgery for trapeziometacarpal joint osteoarthritis is generally good, but patients with higher occupational hand force requirements can expect slower RTW.
Prognostic II.

It has been claimed that Nordic register data are a \"goldmine\" for research. However, one limitation is the lack of information on working conditions. Job exposure matrices (JEMs) are one solution to this problem. Thus, the three aims of this study were (i) to investigate the reliability of an occupation-based psychosocial JEM, i.e., a Job Strain Index (job strain or JSI abbreviated), (ii) to examine the construct and criterion-related validity of this measure of job strain (iii) and assesses the concurrent and the predictive validity of an occupation-based Job Strain Index for use in analyses of Norwegian register data.
The study utilized five waves of the nationwide Norway Survey of Living Conditions in the Work Environment with a total sample of 43,977 individuals and register data with a total sample of 1,589,535 individuals. Job strain was composed of items belonging to the two dimensions of Karasek\'s DC model, job demands and job control (1979). The reliability of the JSI and its dimensions and components were investigated by measuring the degree of agreement (Cohen\'s kappa), sensitivity, specificity, and internal consistency (Cronbach\'s alpha). Construct validity was assessed by confirmatory factor analysis, and criterion-related validity was measured by concurrent validity and predictive validity. The selected concurrent criteria were self-reported survey information on long-term sick absence, anxiety, depression, and sleeping difficulty. The predictive criteria were register information on receipt of disability benefits, mortality, and long-term sick leave.
Agreement between individual and occupation-based job strain and components was fair to poor. The sensitivity and specificity of occupation-based job strain and its components varied from acceptable to low. The consistency of the items comprising job demand and job control was clearly acceptable. Regarding concurrent validity, significant associations between (both individual and occupational) job strain, and long-term sick leave and sleeping difficulty were observed for both genders. Occupation-based job strain indicated an elevated risk for anxiety and depression among men, but not among women. As for predictive reliability, significant associations between occupation-based job strain and all three health outcomes were observed for both men and women.
Our occupation-based JSI serves as a reliable and valid indicator of psychosocial job exposure that can be used in analyses of Norwegian register data where individual information on such conditions is missing.

UNASSIGNED: We aimed to assess the association between occupational noise exposure and long-term hearing decline.
UNASSIGNED: This prospective cohort study used linear regression to investigate the association between occupational noise exposure and 20-year hearing decline, adjusted for important confounders.
UNASSIGNED: The Norwegian cohort (N = 4,448) participated in two population-based health studies with pure-tone audiometry; HUNT2 1996-1998 and HUNT4 2017-2019. Exposure assessments included a quantitative job exposure matrix (JEM) and questionnaires.
UNASSIGNED: The participants (40.2% men, 20-39 years at baseline) had a mean 20-year decline (3-6 kHz) of 11.3 ± 9.8 decibels (dB). There was a positive association between 20-year logarithmic average noise level (JEM-based, LEX,20y) and 20-year hearing decline among men. Compared with no exposure ≥80 dB during follow-up, minimum 5 years of exposure ≥85 dB (JEM-based) predicted 2.6 dB (95% CI: 0.2-5.0) larger 20-year decline for workers aged 30-39 years at baseline, and -0.2 dB (95% CI: -2.2 to 1.7) for workers aged 20-29 years. Combining JEM information with self-reported noise exposure data resulted in stronger associations.
UNASSIGNED: This large longitudinal study shows an association between JEM-based noise exposure level and increased 20-year hearing decline among men. Contrary to expectations, the associations were weaker among younger workers, which might reflect a latency period.

The overall aim of this study was to examine essential aspects of reliability and validity of a constructed Occupational Mechanical Job Exposure Index for use in analyses of Norwegian register data.  METHODS: We utilized data from the Norwegian nationwide Survey of Living Conditions on work environment in 2006, 2009, 2013, 2016 and 2019. Occupations were classified on a 4-digit level based on the Norwegian version of the International Standard Classification of Occupations (ISCO-88). We constructed a 4-digit correspondence table between the occupational codes used in the 2006 and 2009 surveys (STYRK-98) and the codes used in 2013, 2016 and 2019 (STYRK-08). The mechanical exposures were collected by Statistics Norway using telephone interviews. As for reliability, we examined the agreement between the individual- and the occupational-based mechanical exposures using Cohen\'s kappa, sensitivity and specificity measures. Construct, concurrent and predictive validity pertaining to the Occupational Mechanical Job Exposure Index were analysed using both survey data and nationwide register data.
The analysis shows a fair-to-moderate overlap between occupational-based mechanical exposures and the individually reported exposures. Construct validity of the Occupational Mechanical Job Exposure Index, as estimated by a confirmatory factor analysis using the occupational-based mechanical exposures, showed that the 8 exposures formed one underlying factor. When assessing the concurrent value of the Occupational Mechanical Job Exposure Index to the index based on the individual reported exposures, the occupational mechanical index showed lower and reproducible associations with lower back pain for both men and women. For long-term sick leave, the occupational mechanical index showed higher and reproducible associations for both genders. As for predictive validity, the register data analysis shows that the occupational mechanical index was associated with disability and a higher number of long-term sickness benefits periods for both men and women. For men the index also predicted higher mortality.
Our tests of reliability and validity of the Occupational Mechanical Job Exposure Index indicate that the index overall has acceptable statistical properties and will be useful in analyses of Norwegian register data where individual information on these types of exposures is missing.