Occupational patterns of opioid-related harms comparing a cohort of formerly injured workers to the general population in Ontario, Canada.

OBJECTIVES: The role of work-related injuries as a risk factor for opioid-related harms has been hypothesized, but little data exist to support this relationship. The objective was to compare the incidence of opioid-related harms among a cohort of formerly injured workers to the general population in Ontario, Canada. METHODS: Workers' compensation claimants (1983-2019) were linked to emergency department (ED) and hospitalization records (2006-2020). Incident rates of opioid-related poisonings and mental and behavioural disorders were estimated among 1.7 million workers and in the general population. Standardized incidence ratios (SIRs) and 95% confidence intervals (CI) were calculated, adjusting for age, sex, year, and region. RESULTS: Compared to the general population, opioid-related poisonings among this group of formerly injured workers were elevated in both ED (SIR = 2.41, 95% CI = 2.37-2.45) and hospitalization records (SIR = 1.54, 95% CI = 1.50-1.59). Opioid-related mental and behavioural disorders were also elevated compared to the general population (ED visits: SIR = 1.86, 95% CI = 1.83-1.89; hospitalizations: SIR = 1.42, 95% CI = 1.38-1.47). Most occupations and industries had higher risks of harm compared to the general population, particularly construction, materials handling, processing (mineral, metal, chemical), and machining and related occupations. Teaching occupations displayed decreased risks of harm. CONCLUSION: Findings support the hypothesis that work-related injuries have a role as a preventable risk factor for opioid-related harms. Strategies aimed at primary prevention of occupational injuries and secondary prevention of work disability and long-term opioid use are warranted.

RéSUMé: OBJECTIFS: Le rôle des accidents du travail en tant que facteur de risque pour les méfaits liés aux opioïdes a été supposé, mais il existe peu de données pour étayer cette relation. L'objectif était de comparer l'incidence des méfaits liés aux opioïdes dans une cohorte de travailleurs anciennement blessés à la population générale de l'Ontario, au Canada. MéTHODES: Les dossiers de demandes d'indemnisation des travailleurs (1983‒2019) ont été reliés aux dossiers des services d'urgence et d'hospitalisation (2006‒2020). Les taux d'incidence des empoisonnements liés aux opioïdes et des troubles mentaux et comportementaux ont été estimés parmi 1,7 million de travailleurs et dans la population générale. Les ratios d'incidence standardisés (RIS) et les intervalles de confiance (IC) à 95 % ont été calculés en tenant compte de l'âge, du sexe, de l'année et de la région. RéSULTATS: Comparativement à la population générale, les empoisonnements liés aux opioïdes chez ce groupe de travailleurs anciennement blessés étaient élevés dans les dossiers des services d'urgence (RIS = 2,41, IC à 95 % = 2,37-2,45) et d'hospitalisation (RIS = 1,54, IC à 95 % = 1,50-1,59). Les troubles mentaux et comportementaux liés aux opioïdes étaient également élevés par rapport à la population générale (visites aux urgences RIS = 1,86, IC à 95 % = 1,83-1,89; hospitalisations RIS = 1,42, IC à 95 % = 1,38-1,47). La plupart des professions et des secteurs d'activité présentaient des risques de méfaits plus élevés par rapport à la population générale, en particulier la construction, la manutention, le traitement (minéral, métallique, chimique) et l'usinage des matières premières et activités connexes. Les professions de l'enseignement présentaient des risques de méfaits moindres. CONCLUSION: Les résultats confirment l'hypothèse selon laquelle les accidents du travail constituent un facteur de risque évitable pour les méfaits liés aux opioïdes. Des stratégies visant la prévention primaire des accidents du travail et la prévention secondaire de l'incapacité de travail et de la consommation d'opioïdes à long terme sont justifiées.

Risk of chronic obstructive pulmonary disease in a large cohort of Ontario, Canada workers.

Although several occupational exposures have been linked to the risk of COPD; limited data exists on sex-specific differences. This study aimed to identify at-risk occupations and sex differences for COPD risk. Cases were identified in a large surveillance system established through the linkage of former compensation claimants' data (non-COPD claims) to physician visits, ambulatory care data, and hospital inpatient data (1983-2020). Cox proportional hazard models were used to estimate hazard ratios (HRs) and corresponding 95% confidence intervals (CI) for occupation groups (occupation at time of claim), stratified by sex. HRs were indirectly adjusted for cigarette smoking using another population dataset. A total of 29,445 male and 14,693 female incident cases of COPD were identified. Increased risks were observed in both sexes for construction (HRmale 1.15, 95% CI 1.12-1.19; HRfemale 1.54, 95% CI 1.29-1.83) transport/equipment operating (HRmale 1.32, 95% CI 1.28-1.37; HRfemale 1.53, 95% CI 1.40-1.68) farming (HRmale 1.23, 95% CI 1.15-1.32; HRfemale 1.19, 95% CI 1.04-1.37) and janitors/cleaners (HRmale 1.31, 95% CI 1.24-1.37; HRfemale 1.40, 95% CI 1.31-1.49). Increased risks were observed for females employed as chefs and cooks (HR 1.44, 95% CI 1.31-1.58), bartenders (HR 1.38, 95% CI 1.05-1.81), and those working in food/beverage preparation (HR 1.34, 95% CI 1.24-1.45) among other occupations. This study demonstrates elevated risk of COPD among both male and female workers potentially exposed to vapours, gases, dusts, and fumes, highlighting the need for occupational surveillance of COPD.

Incidence of acute myocardial infarction in the workforce: Findings from the Occupational Disease Surveillance System.

BACKGROUND: Increased risks of acute myocardial infarction (AMI) may be attributable to the workplace, however, associations are not well-established. Using the Occupational Disease Surveillance System (ODSS), we sought to estimate associations between occupation and industry of employment and AMI risk among workers in Ontario, Canada. METHODS: The study population was derived by linking provincial accepted lost-time workers' compensation claims data, to inpatient hospitalization records. Workers aged 15-65 years with an accepted non-AMI compensation claim were followed for an AMI event between 2007 and 2016. Adjusted Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for each industry and occupation group, compared to all other workers in the cohort. Sex-stratified analyses were also performed. RESULTS: In all, 24,514 incident cases of AMI were identified among 1,502,072 Ontario workers. Increased incidence rates of AMI were found across forestry (HR 1.37, 95% CI 1.19-1.58) and wood processing (HR 1.50, 1.27-1.77) job-titles. Elevated rates were also detected within industries and occupations both broadly related to mining and quarrying (HR 1.52, 1.17-1.97), trucking (HR 1.32, 1.27-1.38), construction (HR 1.32, 1.14-1.54), and the manufacturing and processing of metal (HR 1.41, 1.19-1.68), textile (HR 1.41, 1.07-1.88), non-metallic mineral (HR 1.30, 0.82-2.07), and rubber and plastic (HR 1.42, 1.27-1.60) products. Female food service workers also had elevated AMI rates (HR 1.36, 1.23-1.51). CONCLUSION: This study found occupational variation in AMI incidence. Future studies should examine work-related hazards possibly contributing to such excess risks, like noise, vibration, occupational physical activity, shift work, and chemical and particulate exposures.

Dermatitis among workers in Ontario: results from the Occupational Disease Surveillance System.

OBJECTIVES: Dermatitis is the most common occupational skin disease, and further evidence is needed regarding preventable risk factors. The Occupational Disease Surveillance System (ODSS) derived from administrative data was used to investigate dermatitis risk among industry and occupation groups in Ontario. METHODS: ODSS cohort members were identified from Workplace Safety and Insurance Board (WSIB) accepted lost time claims. A case was defined as having ≥2 dermatitis physician billing claims during a 12-month period within 3 years of cohort entry. A 3-year look-back period prior to cohort entry was used to exclude prevalent cases without a WSIB claim. Workers were followed for 3 years or until dermatitis diagnosis, age 65 years, emigration, death or end of follow-up (31 December 2016), whichever occurred first. Age-adjusted and sex-adjusted Cox proportional hazard models estimated HRs and 95% CIs. The risk of dermatitis was explored using a job exposure matrix that identifies exposure to asthmagens, many of which also cause contact dermatitis. RESULTS: Among 597 401 workers, 23 843 cases of new-onset dermatitis were identified. Expected elevated risks were observed among several groups including furniture and fixture industries, food and beverage preparation and chemicals, petroleum, rubber, plastic and related materials processing occupations and workers exposed to metal working fluids and organic solvents. Decreased risk was observed among farmers, nurses and construction industries, and occupations exposed to latex and indoor cleaning products. CONCLUSIONS: ODSS can contribute to occupational dermatitis surveillance in Ontario by identifying occupational groups at risk of dermatitis that can then be prioritised for prevention activities.

Prostate cancer risk by occupation in the Occupational Disease Surveillance System (ODSS) in Ontario, Canada. / Risque de cancer de la prostate par profession dans le Système de surveillance des maladies professionnelles de l'Ontario, Canada.

INTRODUCTION: Previous Canadian epidemiologic studies have identified associations between occupations and prostate cancer risk, though evidence is limited. However, there are no well-established preventable risk factors for prostate cancer, which warrants the need for further investigation into occupational factors to strengthen existing evidence. This study uses occupation and prostate cancer information from a large surveillance cohort in Ontario that linked workers' compensation claim data to administrative health databases. METHODS: Occupations were examined using the Occupational Disease Surveillance System (ODSS). ODSS included 1 231 177 male workers for the 1983 to 2015 period, whose records were linked to the Ontario Cancer Registry (OCR) in order to identify and follow up on prostate cancer diagnoses. Cox proportional hazard models were used to calculate age-adjusted hazard ratios and 95% CI to estimate the risk of prostate cancer by occupation group. RESULTS: A total of 34 997 prostate cancer cases were diagnosed among workers in ODSS. Overall, elevated prostate cancer risk was observed for men employed in management/ administration (HR 2.17, 95% CI = 1.98-2.38), teaching (HR 1.99, 95% CI = 1.79-2.21), transportation (HR 1.20, 95% CI = 1.16-1.24), construction (HR 1.09, 95% CI = 1.06-1.12), firefighting (HR 1.62, 95% CI = 1.47-1.78), and police work (HR 1.20, 95% CI = 1.10-1.32). Inconsistent findings were observed for clerical and farming occupations. CONCLUSION: Associations observed in white collar, construction, transportation, and protective services occupations were consistent with previous Canadian studies. Findings emphasize the need to assess job-specific exposures, sedentary behaviour, psychological stress, and shift work. Understanding specific occupational risk factors can lead to better understanding of prostate cancer etiology and improve prevention strategies.

Adult Asthma among Workers in Ontario. Results from the Occupational Disease Surveillance System.

Rationale: Given that approximately 15% of new-onset adult asthma cases originate because of exposures in the workplace, there is a need for systematic and ongoing monitoring of risk among workers. Objectives: To characterize the risk of new-onset adult asthma among workers in Ontario. Methods: We used 575,379 provincial accepted time-loss workers' compensation claimants data linked to physician billing data. Workers aged 15 to 65 years with a nonasthma compensation claim between January 1, 2002, and December 31, 2013, were eligible for inclusion. Cohort entry corresponded to the date of the claim. The case definition required two or more records for asthma within a 12-month period, within a 3-year time window after cohort entry. A 3-year washout period preceding cohort entry was used to exclude prevalent cases. Workers at risk of new-onset adult asthma were followed from cohort entry date to date of diagnosis, emigration, age 65 years, death, or end of study period. Cox regression models were used to generate birth year- and sex-adjusted hazard ratios (HRs) by occupation, industry, and exposures identified using a job exposure matrix. Sex-stratified risk estimates were also generated. Results: Increased risks were detected among well-recognized groups, including bakers (HR, 1.60; 95% confidence interval [CI], 1.22-2.09) and painters and decorators (HR, 1.67; 95% CI, 1.23-2.28). In the job exposure matrix analysis, flour and isocyanates were associated with increased risk of asthma. Concrete finishers (HR, 1.93; 95% CI, 1.12-3.32) and shipping and receiving clerks (HR, 1.21; 95% CI, 1.03-1.43) also showed elevated risk, whereas results varied across woodworker groups. Decreased risks were detected for nursing and farming groups. Conclusions: This practical data linkage approach was successful for examining associations across hundreds of jobs. Unexpected and previously unrecognized findings deserve further investigation and emphasize the importance of an ongoing system to guide research as well as prevention.

Breast cancer risk by occupation and industry in women and men: Results from the Occupational Disease Surveillance System (ODSS).

BACKGROUND: The recently established Occupational Disease Surveillance System (ODSS) was used to examine breast cancer risk in women and men by occupation and industry. METHODS: Ontario workers in the ODSS cohort (1983-2016) were followed up for breast cancer diagnosis through the Ontario Cancer Registry. Cox-proportional hazard models were used to calculate age-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: A total of 17 865 and 492 cases were identified in working women (W) and men (M), respectively. Elevated risks were observed in management (W: HR = 1.54, 95% CI = 1.40-1.70; M: HR = 2.79, 95% CI = 1.44-5.39), administrative/clerical (W: HR = 1.16, 95% CI = 1.11-1.21; M: HR = 1.45, 95% CI = 1.06-1.99), and teaching (W: HR = 1.54, 95% CI = 1.44-1.63; M: HR = 3.00, 95% CI = 1.49-6.03). Other elevated risks were observed in nursing/health, social sciences, and janitor/cleaning services for both genders. CONCLUSIONS: Common occupational associations in both genders warrant investigation into job-related risk factors, such as sedentary behavior, shift work, ionizing radiation, and chemical exposures.

Surveillance of cancer risks for firefighters, police, and armed forces among men in a Canadian census cohort.

BACKGROUND: Firefighters, police, and armed services may be exposed to hazards such as combustion by-products and shift work. METHODS: The CanCHEC cohort linked 1991 census data to the Canadian cancer registry for follow up. Cox proportional hazards modeling was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) to estimate risks for firefighter, police, or armed forces compared to workers in other occupations. RESULTS: The cohort of 1 108 410 men included 4535 firefighters, 10 055 police, and 9165 armed forces. For firefighters, elevated risks were noted for Hodgkin's lymphoma (HR: 2.89, 95%CI: 1.29-6.46), melanoma (HR: 1.67, 95%CI: 1.17-2.37), and prostate cancer (HR: 1.18, 95%CI: 1.01-1.37). Police had elevated risks for melanoma (HR:1.69, 95%CI: 1.32-2.16) and prostate cancer (HR:1.28, 95%CI: 1.14-1.42). No significant associations were found for armed forces workers. CONCLUSIONS: Canadian firefighters, police, and armed services, may be at an increased risk of developing certain cancers. Results suggested that a healthy worker effect may influence risk estimates.

Examining lung cancer risks across different industries and occupations in Ontario, Canada: the establishment of the Occupational Disease Surveillance System.

BACKGROUND: The Occupational Disease Surveillance System (ODSS) was established in Ontario, Canada by linking a cohort of workers with data created from Workplace Safety and Insurance Board (WSIB) claims to administrative health databases. The aim of this study was to use ODSS to identify high-risk industry and occupation groups for lung cancer in Ontario. METHODS: Workers in the WSIB lost time claims database were linked to the Ontario Cancer Registry using subjects' health insurance numbers, name, sex, birthdate and death date (if applicable). Several occupations and industries known to be at increased risk were outlined a priori to examine whether ODSS could replicate these associations. Age-adjusted, sex-stratified Cox proportional hazard models compared the risk of lung cancer within one industry/occupation versus all other groups in the cohort. Workers with a lung cancer diagnosis prior to cohort entry were excluded for analysis, leaving 2 187 762 workers for analysis. RESULTS: During the 1983 to 2014 follow-up, 34 661 workers in the cohort were diagnosed with lung cancer. Among expected high-risk industries, elevated risks were observed among workers in quarries/sand pits and construction industries for both sexes, and among males in metal mines, iron foundries, non-metallic mineral products industries and transportation industries. Excess risk was also observed among occupations in drilling/blasting, other mining/quarrying, mineral ore treating, excavating/grading/paving, truck driving, painting, bus driving and construction. CONCLUSIONS: This current surveillance system identified several established high-risk groups for lung cancer and could be used for ongoing surveillance of occupational lung cancer in Ontario.

Cancer Risks among Welders and Occasional Welders in a National Population-Based Cohort Study: Canadian Census Health and Environmental Cohort.

BACKGROUND: Welders are exposed to many known and suspected carcinogens. An excess lung cancer risk among welders is well established, but whether this is attributable to welding fumes is unclear. Excess risks of other cancers have been suggested, but not established. We investigated welding cancer risks in the population-based Canadian Census Health and Environmental Cohort. METHODS: Among 1.1 million male workers, 12,845 welders were identified using Standard Occupational Classification codes and followed through retrospective linkage of 1991 Canadian Long Form Census and Canadian Cancer Registry (1992-2010) records. Hazard ratios (HRs) were calculated using Cox proportional hazards models based on estimated risks of lung cancer, mesothelioma, and nasal, brain, stomach, kidney, and bladder cancers, and ocular melanoma. Lung cancer histological subtypes and risks by industry group and for occasional welders were examined. Some analyses restricted comparisons to blue-collar workers to minimize effects of potential confounders. RESULTS: Among welders, elevated risks were observed for lung cancer [HR: 1.16, 95% confidence interval (CI): 1.03-1.31], mesothelioma (HR: 1.78, 95% CI: 1.01-3.18), bladder cancer (HR: 1.40, 95% CI: 1.15-1.70), and kidney cancer (HR: 1.30, 95% CI: 1.01-1.67). When restricted to blue-collar workers, lung cancer and mesothelioma risks were attenuated, while bladder and kidney cancer risks increased. CONCLUSION: Excess risks of lung cancer and mesothelioma may be partly attributable to factors including smoking and asbestos. Welding-specific exposures may increase bladder and kidney cancer risks, and particular sources of exposure should be investigated. Studies that are able to disentangle welding effects from smoking and asbestos exposure are needed.

Cancer risks in a population-based study of 70,570 agricultural workers: results from the Canadian census health and Environment cohort (CanCHEC).

BACKGROUND: Agricultural workers may be exposed to potential carcinogens including pesticides, sensitizing agents and solar radiation. Previous studies indicate increased risks of hematopoietic cancers and decreased risks at other sites, possibly due to differences in lifestyle or risk behaviours. We present findings from CanCHEC (Canadian Census Health and Environment Cohort), the largest national population-based cohort of agricultural workers. METHODS: Statistics Canada created the cohort using deterministic and probabilistic linkage of the 1991 Canadian Long Form Census to National Cancer Registry records for 1992-2010. Self-reported occupations were coded using the Standard Occupational Classification (1991) system. Analyses were restricted to employed persons aged 25-74 years at baseline (N = 2,051,315), with follow-up until December 31, 2010. Hazard ratios (HR) and 95% confidence intervals (CI) were modeled using Cox proportional hazards for all workers in agricultural occupations (n = 70,570; 70.8% male), stratified by sex, and adjusted for age at cohort entry, province of residence, and highest level of education. RESULTS: A total of 9515 incident cancer cases (7295 in males) occurred in agricultural workers. Among men, increased risks were observed for non-Hodgkin lymphoma (HR = 1.10, 95% CI = 1.00-1.21), prostate (HR = 1.11, 95% CI = 1.06-1.16), melanoma (HR = 1.15, 95% CI = 1.02-1.31), and lip cancer (HR = 2.14, 95% CI = 1.70-2.70). Decreased risks in males were observed for lung, larynx, and liver cancers. Among female agricultural workers there was an increased risk of pancreatic cancer (HR = 1.36, 95% CI = 1.07-1.72). Increased risks of melanoma (HR = 1.79, 95% CI = 1.17-2.73), leukemia (HR = 2.01, 95% CI = 1.24-3.25) and multiple myeloma (HR = 2.25, 95% CI = 1.16-4.37) were observed in a subset of female crop farmers. CONCLUSIONS: Exposure to pesticides may have contributed to increased risks of hematopoietic cancers, while increased risks of lip cancer and melanoma may be attributed to sun exposure. The array of decreased risks suggests reduced smoking and alcohol consumption in this occupational group compared to the general population.