Surveillance of potential associations between occupations and causes of death in Canada, 1965-91

Health Comparisons Between Truck Drivers and the General Population Using the Canadian Community Health Survey

BACKGROUND

This study examined and compared risk factors and health conditions of truck drivers compared with the general Canadian population.

METHODS

This study used the Canadian Community Health Survey consisting of 991 male truck drivers and 29,958 male respondents of the general population.

RESULTS

Compared with the general population, truck drivers were older, less educated, had lower incomes, worked more hours, and were more likely to be widowed/separated/divorced. In addition, truck drivers had significantly higher rates of cardiovascular disease and obesity and were more likely to be sedentary, smoke, drive when fatigued, and eat unhealthy compared with the general population.

CONCLUSIONS

Multicomponent interventions are needed to address the poor lifestyle practices of truckers to reduce the high rates of morbidity.

Respiratory Tract Cancer Incidences across Industry Groups: A Nationwide Cohort Study with More Than 70 Million Person-Years of Follow-Up

The number of cases and incidence rates of laryngeal and lung cancers have been increasing globally. Therefore, identifying the occupational causes of such cancers is an important concern for policymakers to prevent cancers and deaths. We used national health insurance service claims data in Korea. We included 10,786,000 workers aged between 25 and 64 years. In total, 74,366,928 total person-years of follow-up were included in this study with a mean follow-up of 6.89 years for each person. The standardized incidence ratio (SIR) and 95% confidence intervals (CIs) referenced with the total workers were estimated. For laryngeal cancer, increased SIRs were observed in the land transportation industry among male workers (SIR [95% CI]: 1.65 [1.02–2.53]). For lung cancer, elevated SIRs were observed in the industries including animal production (1.72 [1.03–2.68]), fishing (1.70 [1.05–2.60]), mining (1.69 [1.22–2.27]), travel (1.41 [1.00–1.93]), and transportation (1.22 [1.15–1.30]) among male workers. For female works, healthcare (2.08 [1.04–3.72]) and wholesale (1.88 [1.18–2.85]) industries were associated with a high risk of lung cancer. As an increased risk of respiratory tract cancers has been identified in employees associated with certain industries, appropriate policy intervention is needed to prevent occupational cancers.

Health and wellness of Canadian commercial motor vehicle drivers

Purpose

The purpose of this paper is to solicit perspectives from stakeholders concerning health, environmental and operational challenges among Commercial motor vehicle (CMV) drivers in Canada (truck and bus drivers).

Design/methodology/approach

Two focus groups and one interview were conducted with key industry, government and advocacy groups representing or working with CMV drivers. Perspectives pertaining to working conditions, health issues, driver recruitment and retention, and other key issues in the CMV sector were obtained.

Findings

The findings show that undesirable working conditions are primary issues that impact recruitment and retention, as well as health and wellness (H&W), and productivity of drivers in both the truck and bus sectors. Compared to our US counterparts, finding parking areas and rest stops were seen as a major issue for Canadian truckers (particularly in the north). Unfortunately, there is limited or out-dated information on drivers and companies in Canada. Stakeholders stated the need for more information from both carriers/companies and from drivers themselves (particularly long-haul drivers).

Research limitations/implications

This study identifies gaps and key priority research areas pertaining to the H&W of the CMV sector in Canada that require further investigation.

Originality/value

CMV drivers are considered a vulnerable sector of the population. While drivers themselves have reported on undesirable work conditions leading to poor health, prior studies have not assessed the awareness or perspective of stakeholders involved in the CMV sector. This is the first study to capture stakeholder perspectives of the working conditions and health outcomes of CMV drivers.

Cross-sectional surveillance study to phenotype lorry drivers' sedentary behaviours, physical activity and cardio-metabolic health

OBJECTIVES

Elevated risk factors for a number of chronic diseases have been identified in lorry drivers. Unhealthy lifestyle behaviours such as a lack of physical activity (PA) and high levels of sedentary behaviour (sitting) likely contribute to this elevated risk. This study behaviourally phenotyped UK lorry drivers' sedentary and non-sedentary behaviours during workdays and non-workdays and examined markers of drivers cardio-metabolic health.

SETTING

A transport company from the East Midlands, UK.

PARTICIPANTS

A sample of 159 male heavy goods vehicle drivers (91% white European; (median (range)) age: 50 (24, 67) years) completed the health assessments. 87 (age: 50.0 (25.0, 65.0); body mass index (BMI): 27.7 (19.6, 43.4) kg/m²) provided objective information on sedentary and non-sedentary time.

OUTCOMES

Participants self-reported their sociodemographic information. Primary outcomes: sedentary behaviour and PA, assessed over 7 days using an activPAL3 inclinometer. Cardio-metabolic markers included: blood pressure (BP), heart rate, waist circumference (WC), hip circumference, body composition and fasted capillary blood glucose, triglycerides, high-density lipopreotein cholesterol, low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC) levels. These cardio-metabolic markers were treated as secondary outcomes.

RESULTS

Lorry drivers presented an unhealthy cardio-metabolic health profile (median (IQR) systolic BP: 129 (108.5, 164) mm Hg; diastolic BP: 81 (63, 104) mm Hg; BMI: 29 (20, 47) kg/m²; WC: 102 (77.5, 146.5) cm; LDL-C: 3 (1, 6) mmol/L; TC: 4.9 (3, 7.5) mmol/L). 84% were overweight or obese, 43% had type 2 diabetes or prediabetes and 34% had the metabolic syndrome. The subsample of lorry drivers with objective postural data (n=87) accumulated 13 hours/day and 8 hours/day of sedentary behaviour on workdays and non-workdays (p<0.001), respectively. On average, drivers accrued 12 min/day on workdays and 6 min/day on non-workdays of moderate-to-vigorous PA (MVPA).

CONCLUSION

Lorry drivers demonstrate a high-risk cardio-metabolic profile and are highly sedentary and physically inactive. Interventions to reduce sitting and increase MVPA during breaks and leisure time to improve cardio-metabolic health are urgently needed. Educational programmes to raise awareness about diet and exercise are recommended.

Occupation and risk of prostate cancer in Canadian men: A case-control study across eight Canadian provinces

BACKGROUND

The etiology of prostate cancer continues to be poorly understood, including the role of occupation. Past Canadian studies have not been able to thoroughly examine prostate cancer by occupation with detailed information on individual level factors.

METHODS

Occupation, industry and prostate cancer were examined using data from the National Enhanced Cancer Surveillance System, a large population-based case-control study conducted across eight Canadian provinces from 1994 to 1997. This analysis included 1737 incident cases and 1803 controls aged 50 to 79 years. Lifetime occupational histories were used to group individuals by occupation and industry employment. Odds ratios and 95% confidence intervals were calculated and adjustments were made for known and possible risk factors.

RESULTS

By occupation, elevated risks were observed in farming and farm management (OR=1.37, 95% CI 1.02-1.84), armed forces (OR=1.33, 95% CI 1.06-1.65) and legal work (OR=2.58, 95% CI 1.05-6.35). Elevated risks were also observed in office work (OR=1.20, 95% CI 1.00-1.43) and plumbing (OR=1.77, 95% CI 1.07-2.93) and with ≥10 years duration of employment. Decreased risks were observed in senior management (OR=0.65, 95% CI 0.46-0.91), construction management (OR=0.69, 95% CI 0.50-0.94) and travel work (OR=0.37, 95% CI 0.16-0.88). Industry results were similar to occupation results, except for an elevated risk in forestry/logging (OR=1.54, 95% CI 1.06-2.25) and a decreased risk in primary metal products (OR=0.70, 95% CI 0.51-0.96).

CONCLUSION

This study presents associations between occupation, industry and prostate cancer, while accounting for individual level factors. Further research is needed on potential job-specific exposures and screening behaviours.

Screening for common occupational health diseases among long distance professional drivers in sagamu, ogun state, Nigeria

BACKGROUND

Long term exposure to hazards at the work place is injurious to health and usually leads to diseased conditions. The objective of this study was to determine the occupational health problems associated with driving among the professional drivers in Sagamu, Ogun state, Nigeria.

METHODS

This study is a cross-sectional study. Total sample of all the consenting professional drivers in the five interstate motor parks, including the cement factory [WAPCO] in the local government area, were recruited into the study. An interviewer administered structured questionnaire was administered by trained health workers and respondents were screen for common occupational health problems.

RESULTS

A total of 400 professional drivers were interviewed, all [100%] of them were males with age range from 21 to 59 yrs and nearly half [42%] were non indigenes. Only half, 208 [52%] of them were married with majority, 232 [58.0%] working for about 12 hrs daily and 46% of them had been working for 5 yrs or more. Most, 382 [95.5%] had been educated on HIV/AIDS before and 313 [78.3%] of them had multiple sexual partners. Only 241 [60.3%] used condom at the last sexual act and 55 [13.5%] had ever been tested for HIV/AIDS. Common occupational health diseases were renal tubular acidosis (RTA) 52 [13%] in the last one year and most of them currently have myalgia 352 [88.0%], upper respiratory tract infections (URTI) 20 [5.0%], sexually transmitted diseases (STD) 15 [3.8%], short sightedness 41 [10.3%], and Hypertension 90 [22.5%].

CONCLUSIONS

The study shows that common occupational diseases among long distance professional drivers in Western Nigeria were myalgia, upper respiratory tract infection, hypertension, short sightedness, sexually transmitted diseases, and RTA. Prevention and control of these common diseases among the drivers will lead to reduction of road traffic accidents in Western Nigeria and other low income countries.

Quality of online physical activity information for long-haul truck drivers

Purpose

– Most long-haul truck drivers are physically inactive. Despite being identified as a source of health information, online physical activity and exercise information has not been evaluated for this population. The purpose of this paper is to evaluate the accessibility, accuracy, technical and theoretical quality, and readability of online physical activity, exercise, and sport information for long-haul truck drivers.

Design/methodology/approach

– A standardized protocol was followed to identify and evaluate web sites. Web sites were included in the review if they met the following criteria: first, presented information on physical activity, exercise, or sport; second, provided information for long-haul truck drivers; and finally, provided information in English. Each web site was evaluated independently by the two study authors. After evaluating the web sites independently, the authors then met to discuss each construct for each web site.

Findings

– Overall, 44 web sites were reviewed. Nine web sites provided information based on physical activity guidelines. Most web sites scored poorly on technical and theoretical quality. In total, 28 web sites provided information that was written above the recommended grade 8 reading level.

Research limitations/implications

– Research has shown that theoretically designed physical activity and exercise interventions are more successful than those with no theoretical underpinnings. Creating web sites or online applications using behavioral theory and improving the readability of online health information may help increase levels of physical activity and improve overall health for this population.

Originality/value

– No previous research has examined the quality of online physical activity, exercise, or sport information for long-haul truck drivers. This is the first study to examine how online health information for this population can be improved.

Trends in compensation for deaths from occupational cancer in Canada: a descriptive study

BACKGROUND

Occupational cancer is the leading cause of work-related deaths, yet it is often unrecognized and under reported, and associated claims for compensation go unfiled. We sought to examine trends in deaths from occupational cancer, high-risk industries and exposures, and commonly compensated categories of occupational cancers. In addition, we compared deaths from occupational lung cancer for which compensation had been given with total deaths from lung cancer.

METHODS

We used data from the Association of Workers' Compensation Boards of Canada pertaining to the nature and source of the injury or disease and the industry in which it occurred (by jurisdiction) to describe trends in compensated claims for deaths from occupational cancer in Canada for the period 1997-2010. We used data published by the Canadian Cancer Society in Canadian Cancer Statistics to compare compensated occupational lung cancer deaths with total estimated lung cancer deaths for the period between 2006 and 2010.

RESULTS

Compensated claims for deaths from occupational cancer have increased in recent years and surpassed those for traumatic injuries and disorders in Canada, particularly in Ontario. Between 1997 and 2010, one-half of all compensated deaths from occupational cancer in Canada were from Ontario. High-risk industries for occupational cancer include manufacturing, construction, mining and, more recently, government services. Deaths from lung cancer and mesothelioma comprise most of the compensated claims for deaths from occupational cancer in Ontario and Canada. These diseases are usually the result of asbestos exposure. The burden of other occupational carcinogens is not reflected in claims data.

INTERPRETATION

Although the number of accepted claims for deaths from occupational cancers has increased in recent years, these claims likely only represent a fraction of the true burden of this problem. Increased education of patients, workers at high risk of exposure and health care providers is needed to ensure that people with work-related cancer are identified and file a claim for compensation.

Prevalence of undiagnosed diabetes mellitus and cardiovascular risk factors in Hong Kong professional drivers

AIMS

To investigate the prevalence of undiagnosed diabetes mellitus (DM) and cardiovascular risk factors among professional drivers in Hong Kong.

METHODS

Chinese professional drivers with no history of DM were invited to complete a questionnaire on their health status, followed by taking their body measurements, fasting blood glucose (FG) and lipids. 75g OGTT were performed when FG≥5.6 to <7.0mmol/L.

RESULTS

Of these 3376 drivers (male 92.6%, mean age 50.9±7.6 years), the prevalence of undiagnosed DM, prediabetes, and metabolic syndrome was 8.1% (272/3376, 95% CI 7.1-9.0%), 10.0% (337/3376, 95% CI 9.0-11.0%) and 26.8% (904/3376, 95% CI 25.3-28.3%) respectively, while the corresponding WHO Standard Population age-standardized prevalence was 7.8%, 9.0% and 24.7% respectively. Many of them were obese (51.2%), had hypertension (57.0%) and high cholesterol (58.7%), and a third had hypertriglyceridaemia (34.9%) and low HDL-cholesterol (29.3%). Their median working hours were 60.0 (IQR 14)h. Majority had exercise <1h/week (56.0%) and ate out ≥6times/week (54.9%).

CONCLUSIONS

Hong Kong professional drivers have higher prevalence of undiagnosed DM, cardiovascular risk factors and metabolic syndrome than the general population. Therefore, health care measures targeting against them should be taken to prevent and detect DM and cardiovascular diseases.

Elevated serum liver enzymes and fatty liver changes associated with long driving among taxi drivers

BACKGROUND

Previous studies suggested increased morbidities and mortalities of liver diseases in drivers.

METHODS

To examine whether driving (monthly driving distance; tenure) is associated with elevated alanine aminotransferase (ALT), aspartate aminotransferase (AST), or chronic fatty liver (FL) changes, we performed a cross-sectional, secondary analysis of the Taxi Drivers' Health Study (n = 1,355), adjusting for clinical, demographic, and lifestyle factors.

RESULTS

Prevalence of elevated ALT, elevated AST, and fatty liver changes were 22.0%, 5.1%, and 9.3%, respectively. Driving distance had a positive association with elevated ALT with a prevalence ratio of 1.35 (95% CI: 0.98, 1.89) comparing the highest versus lowest driving quartile. This association differed by alcohol use, with a corresponding prevalence ratio of 2.08 (95% CI: 1.30, 3.33) among "past/current" drinkers but no association among "never" drinkers. Similar patterns were found for AST, but estimates were less stable. We found a curvilinear response pattern for fatty liver changes; prevalence first increased with years as a taxi driver and then receded in the highest ranges of driving tenure, regardless of the alcohol history.

CONCLUSIONS

Our results provide evidence that long driving is associated with both short-term and chronic liver insults, although alcohol use appears to modify this putative effect.

Avoidable mortality for causes amenable to medical care, by occupation in Canada, 1991-2001

OBJECTIVE

To describe the incidence of avoidable mortality for causes amenable to medical care among occupation groups in Canada.

METHOD

A cohort study over an 11-year period among a representative 15% sample of the non-institutionalized population of Canada aged 30-69 at cohort inception. Age-standardized mortality rates for causes amenable to medical care and all other causes of death were calculated for occupationally-active men and women in five categories of skill level and 80 specific occupational groups as well as for persons not occupationally active.

RESULTS

Age-standardized mortality rates per 100,000 person-years at risk for causes amenable to medical care and for all other causes were 132.3 and 218.6, respectively, for occupationally-active women, and 216.6 and 449.3 for occupationally-active men. For causes amenable to medical care and for all other causes, for both sexes, there was a gradient in mortality relative to the five-level ranking by occupational skill level, but the gradient was less strong for women than for men. Across the 80 occupation minor groups, for both men and women, there was a linear relationship between the rates for causes amenable to medical care and the rates for all other causes.

CONCLUSIONS

For occupationally-active adults, this study found similar gradients in mortality for causes amenable to medical care and for all other causes of mortality over the period 1991-2001. Avoidable mortality is a valuable indicator of population health, providing information on outcomes pertinent to the organization and delivery of health care services.

Occupational demands and health effects for bricklayers and construction supervisors: A systematic review

BACKGROUND

knowledge was gathered on occupational demands and health effects of two occupations in the construction industry, bricklayers and supervisors, in order to design a job-specific workers' health surveillance (WHS) for construction workers.

METHODS

we systematically searched MEDLINE, EMBASE, PsycINFO, HSELINE, NIOSHTIC-2, and Picarta up to December 2008.

RESULTS

a total of 60 articles were included. Evidence was found for the following demands for bricklayers: energetic load (exceeding 25% heart rate reserve), load on the lower back (exceeding the NIOSH-threshold value of 3.4 kN), repetitive force exertions of the upper extremities, frequent bending with trunk flexion exceeding 60° and working with the arms more than 60° elevated. Environmental demands include: dust and quartz exposure (exceeding the limit values of 3.0 and 0.05 mg/m(3), respectively), vibration and noise (exceeding the limit value of 80 dBA). Bricklayers are at increased risk of lung cancer, low back pain, complaints of arms and legs and getting injuries. Among construction supervisors are walking and standing common physically demanding activities. Psychosocial demands with evidence for supervisors were mental demands, workload, time pressure, working long hours, and social-organizational factors. Supervisors are at increased risk of lung cancer and injuries.

CONCLUSIONS

for bricklayers evidence was found for physical demands and risk on low back pain and complaints of arms and legs, for construction supervisors on psychosocial demands. Both occupations are at increased risk of lung cancer and injuries. Job-specific demands and health effects should be incorporated in WHS for construction workers.

Worksite-induced morbidities among truck drivers in the United States

A critical review was conducted of social, psychological, and health science literature on the array of health risks and morbidities of truckers. Multilevel worksite-induced strains (e.g., long work hours and fatigue, shift work and sleep deprivation, postural fatigue and exposure to noise and vibration, sedentary lifestyle and unhealthy diet, exposure to diesel exhaust fumes, and other occupational stressors) were categorized into six primary morbidities for truckers: (1) psychological and psychiatric disorders; (2) detriments resulting from disrupted biological cycles; (3) musculoskeletal disorders; (4) cancer and respiratory morbidities; (5) cardiovascular disease; and (6) risk-laden substance use and sexual practices. Elevated morbidity risks suggest the need for the design and implementation of systematic epidemiological research and environmental interventions in the transport sector.

Worksite-Induced Morbidities among Truck Drivers in the United States

A critical review was conducted of social, psychological, and health science literature on the array of health risks and morbidities of truckers. Multilevel worksite-induced strains (e.g., long work hours and fatigue, shift work and sleep deprivation, postural fatigue and exposure to noise and vibration, sedentary lifestyle and unhealthy diet, exposure to diesel exhaust fumes, and other occupational stressors) were categorized into six primary morbidities for truckers: (1) psychological and psychiatric disorders; (2) detriments resulting from disrupted biological cycles; (3) musculoskeletal disorders; (4) cancer and respiratory morbidities; (5) cardiovascular disease; and (6) risk-laden substance use and sexual practices. Elevated morbidity risks suggest the need for the design and implementation of systematic epidemiological research and environmental interventions in the transport sector.

Suicide mortality by occupation in Canada, 1991-2001

OBJECTIVE

To describe the association between occupation and risk of suicide among working-age men and women in Canada.

METHOD

This study of suicide mortality over an 11-year period is based on a broadly representative 15% sample of the noninstitutionalized population of Canada aged 30 to 69 years at cohort inception. Age-standardized mortality rates (ASMRs) and rate ratios were calculated for men and women in 5 categories of skill level and 80 specific occupational groups, as well as for people not occupationally active.

RESULTS

The suicide mortality rate was 20.1/100 000 person years for occupationally active men (during 9 600 000 person years of follow-up) and 5.3/100 000 person years for occupationally active women (during 8 100 000 person years of follow-up). Among occupationally active men, elevated rates of suicide mortality were observed for 9 occupational groups and protective effects were observed for 6 occupational groups. Among women, elevated rates of suicide were observed in 4 occupational groups and no protective effects were observed. For men and women, ASMRs for suicide were inversely related to skill level.

CONCLUSIONS

The limited number of associations between occupational groups and suicide risk observed in this study suggests that, with few exceptions, the characteristics of specific occupations do not substantially influence the risk for suicide. There was a moderate gradient in suicide mortality risk relative to occupational skill level. Suicide prevention strategies in occupational settings should continue to emphasize efforts to restrict and limit access to lethal means, one of the few suicide prevention policies with proven effectiveness.

Lung cancer and occupation in a population-based case-control study

The authors examined the relation between occupation and lung cancer in the large, population-based Environment And Genetics in Lung cancer Etiology (EAGLE) case-control study. In 2002-2005 in the Lombardy region of northern Italy, 2,100 incident lung cancer cases and 2,120 randomly selected population controls were enrolled. Lifetime occupational histories (industry and job title) were coded by using standard international classifications and were translated into occupations known (list A) or suspected (list B) to be associated with lung cancer. Smoking-adjusted odds ratios and 95% confidence intervals were calculated with logistic regression. For men, an increased risk was found for list A (177 exposed cases and 100 controls; odds ratio = 1.74, 95% confidence interval: 1.27, 2.38) and most occupations therein. No overall excess was found for list B with the exception of filling station attendants and bus and truck drivers (men) and launderers and dry cleaners (women). The authors estimated that 4.9% (95% confidence interval: 2.0, 7.8) of lung cancers in men were attributable to occupation. Among those in other occupations, risk excesses were found for metal workers, barbers and hairdressers, and other motor vehicle drivers. These results indicate that past exposure to occupational carcinogens remains an important determinant of lung cancer occurrence.

Review of the etiology of breast cancer with special attention to organochlorines as potential endocrine disruptors

Breast cancer is the most frequently diagnosed cancer among Canadian women, accounting for about 30% of all new cancer cases each year. Although the incidence of breast cancer has increased over the past 50 years, the cause of this rise is unknown. Risk factors for breast cancer may be classified into four broad categories: (1) genetic/familial, (2) reproductive/hormonal, (3) lifestyle, and (4) environmental. Established risk factors for breast cancer include older age, later age at first full-term pregnancy, no full-term pregnancies, postmenopausal obesity, and genetic factors. However, these known risk factors cannot account for the majority of cases. In the early 1990s, it was suggested that exposure to some environmental chemicals such as organochlorine compounds may play a causal role in the etiology of breast cancer through estrogen-related pathways. The relationship between organochlorines and breast cancer risk has been studied extensively in the past decade and more, and at this point there is no clear evidence to support a causal role of most organochlorine pesticides in the etiology of human breast cancer, but more evidence is needed to assess risk associated with polychlorinated biphenyls (PCBs). Future studies need to consider the combined effects of exposures, concentrate on vulnerable groups such as those with higher levels of exposure, only consider exposures occurring during the most etiologically relevant time periods, and more thoroughly consider gene-environment interactions.

The Italian surveillance system for occupational cancers: characteristics, initial results, and future prospects

BACKGROUND

Occupational cancer monitoring is important for cancer prevention and public health protection. A surveillance system for identifying occupational cancer risks and cancer cases in Italy that are likely to be of occupational origin using information available in the Italian Social Security archives was created and assessed. Persons employed in the private sector, the employing company, its industrial sector, and years of employment are available in these archives.

METHODS

A method to find known occupational hazards was first tested using a case-control approach. Cases were from six Italian cancer registries (CRs) and controls were sampled from source populations and as "exposure" the economic sector of the employing company was used. The potential of using hospital discharge records as case sources was subsequently assessed: these cover larger populations and are available more quickly than CR case series.

RESULTS

In the CR-based study many known occupational cancer risks related to specific industrial sectors were identified. By using cases from hospital discharge records many industries at risk were identified, as well as cases of recent diagnosis likely to be of occupational origin. However, for some industrial sectors (e.g., the chemical industry) the approach was unable to detect any excess risk. Furthermore, information on employees in important areas like agriculture, self-employment, and the public sector is not available in the Social Security archives.

CONCLUSIONS

This approach appears to be a promising low-cost method for occupational cancer surveillance, at least for some industries, and can be easily implemented in other countries.

Occupation related pesticide exposure and cancer of the prostate: a meta-analysis

AIMS

To summarise recent literature on the risk of prostate cancer in pesticide related occupations, to calculate the meta-rate ratio, and to compare it to data from meta-analyses previously published.

METHODS

A meta-analysis of 22 epidemiological studies, published between 1995 and 2001, was conducted in order to pool their rate ratio estimates. Studies were summarised and evaluated for homogeneity and publication bias.

RESULTS

The meta-rate ratio estimate, based on 25 estimators of relative risk from 22 studies, was 1.13 (95% CI 1.04 to 1.22). Significant heterogeneity of rate ratios existed among the different studies. Therefore, a stratified analysis was carried out. Major sources of heterogeneity identified were geographic location, study design, and healthy worker effect. Overall, pooled risk estimates for studies derived from Europe were lower than those derived from the USA/Canada. A significant increase in rate ratio was observed for the occupation category of pesticide applicators, whereas no significant increase was observed for farmers. There was no evidence of publication bias.

CONCLUSION

This increased meta-rate ratio for prostate cancer in different pesticide related occupations, including farmers, is very similar to three, previously published, meta-rate ratios for prostate cancer in farmers calculated from studies published before 1995. Although the underlying data do not identify pesticide exposure as an independent cause for prostate cancer, the fact that an increased meta-rate ratio is again obtained points to occupational exposure to pesticides as a possible factor. Future epidemiological studies should focus, as far as possible, on reliable methods to estimate actual exposure.

Hospital admissions among male drivers in Denmark

OBJECTIVES

To facilitate decisions about interventions and to establish baseline values for future evaluation of preventive efforts, the aim of the present study was to elucidate the disease pattern among male professional drivers in Denmark. The study differentiated between drivers of goods vehicles and drivers of passenger transport.

METHODS

Cohorts of all 20-59 year old Danish male professional drivers in the years 1981, 1986, 1991, and 1994 were formed, to calculate age standardised hospital admission ratios (SHRs) and time trends (1981-97) for many diagnostic aggregations.

RESULTS

SHRs for diseases in practically all systems and organs of the body were higher among professional drivers than they were in the male working population at large. Also drivers of passenger transport, compared with drivers of goods vehicles, had significantly high SHRs due to infectious and parasitic diseases, diseases of the circulatory system, and diseases of the respiratory system, and significantly lower rates of injury. For both driver groups, the SHRs for acute myocardial infarction increased with time whereas the SHR for acute gastritis decreased, and for drivers of passenger transport an increasing SHR for chronic obstructive pulmonary disease, was found over time.

CONCLUSION

Drivers of passenger transport and drivers of goods vehicles differ in their disease patterns. The results support the hypothesis that preventive efforts are needed in both groups, but underline that different strategies are required for different categories of drivers.

Cancer mortality among males in relation to exposures assessed through a job-exposure matrix

To identify potential associations between workplace exposures and cancer mortality risks, job titles collected from 1965 to 1971 for 58,678 men (a subset of a large representative sample of the Canadian workforce) were transformed into probable chemical exposures using a job-exposure matrix developed in Montreal. Mortality follow-up was determined through computerized record linkage with the National Mortality Database in Canada for 1965-1991. Cancer mortality risk was evaluated at two levels of exposure, any and substantial, using Poisson regression controlling for age, calendar period, and social class. Among the 58,678 men, 3,160 died of cancer. Using a liberal reporting criterion, relative risk (RR) >1.0, five or more exposed cancer deaths, p < or = 0.100, several potential associations were identified, including: lung cancer and any exposure to abrasives dust (RR = 2.84), prostate cancer and any exposure to calcium carbonate (RR = 2.46), and prostate cancer and substantial exposure to metallic dust (RR = 2.13).