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Lifetime physical activity and risk of breast cancer in pre-and post-menopausal women

Abstract To investigate the association between different types of physical activity (PA) and breast cancer. A case–control study of breast cancer was conducted in Western Australia from 2009 to 2011, in which 1205 women with breast cancer and 1789 frequency age-matched breast cancer-free control women were recruited. A self-administered questionnaire was used to collect information about lifetime and age-period recreational, household, occupational and transport physical activities. Detailed questions about demographic characteristics, and relevant reproductive, medical and lifestyle factors were also included. Logistic regression and restrictive cubic spline analyses were applied to investigate the association and dose–response relationship between PA and breast cancer risk. Subgroup analysis was performed regarding menopausal status. We found non-linear dose–response associations between PA and risk of breast cancer. Overall, 95–130 MET-hours/week of total lifetime PA was associated with the lowest breast cancer risk. The effects were stronger among post-menopausal women. We also found that the medium amounts of recreational PA (up to 21 MET-hours/week) were associated with lower breast cancer risk among post-menopausal women. Further analysis on the intensity of recreational PA demonstrated different dose–response associations between moderate- and vigorous-intensity recreational PA and breast cancer risk. We found that PA was associated with a reduced risk of breast cancer among post-menopausal women, but not in a linear fashion. Recreational PA of different intensities may have different dose–response associations with risk of breast cancer.

The future excess fraction of occupational cancer among those exposed to carcinogens at work in Australia in 2012

BACKGROUND Studies in other countries have generally found approximately 4% of current cancers to be attributable to past occupational exposures. This study aimed to estimate the future burden of cancer resulting from current occupational exposures in Australia. METHODS The future excess fraction method was used to estimate the future burden of occupational cancer (2012-2094) among the proportion of the Australian working population who were exposed to occupational carcinogens in 2012. Calculations were conducted for 19 cancer types and 53 cancer-exposure pairings, assuming historical trends and current patterns continued to 2094. RESULTS The cohort of 14.6 million Australians of working age in 2012 will develop an estimated 4.8 million cancers during their lifetime, of which 68,500 (1.4%) are attributable to occupational exposure in those exposed in 2012. The majority of these will be lung cancers (n=26,000), leukaemias (n=8000), and malignant mesotheliomas (n=7500). CONCLUSIONS A significant proportion of future cancers will result from occupational exposures. This estimate is lower than previous estimates in the literature; however, our estimate is not directly comparable to past estimates of the occupational cancer burden because they describe different quantities - future cancers in currently exposed versus current cancers due to past exposures. The results of this study allow us to determine which current occupational exposures are most important, and where to target exposure prevention.

Prevalence of occupational exposure to asthmagens derived from animals, fish and/or shellfish among Australian workers

Objective Several animal, fish and/or shellfish derived substances encountered in the workplace can initiate or exacerbate asthma. The aims of this study were: to produce a population-based estimate of the current prevalence of occupational exposure to animal, fish and/or shellfish derived asthmagens, to identify the main circumstances of exposures and to identify occupations with the highest proportions of exposed respondents. Methods We used data from the Australian Work Exposure Study-Asthma, a national telephone survey that investigated the current prevalence of occupational exposure to asthmagens among Australian workers. A web-based tool was used to collect job task information and assign exposure to asthmagens, including animal, fish and/or shellfish derived asthmagens. Prevalence ratios to determine risk factors for exposure were estimated using modified Poisson regression. Results Of the 4878 respondents, 12.4% were exposed to asthmagens derived from animals, fish and/or shellfish. Exposure to these asthmagens was significantly higher in workers residing in regional and remote areas, compared with major cities. The main circumstance of exposure to animal derived asthmagens was through cleaning up rat/mice infestations, while the main circumstance of exposure to fish and/or shellfish derived asthmagens was through preparing and cooking salmon. Occupational groups with the highest proportion of exposure to animal or fish and/or shellfish derived asthmagens were farmers/animal workers and food workers, respectively. Conclusions This is the first study investigating occupational exposure to animal, fish and/or shellfish derived asthmagens in a nationwide working population. The results of this study can be used to inform the direction of occupational interventions and policies to reduce work-related asthma.

Association between shiftwork and the risk of colorectal cancer in females: a population-based case–control study

Objective Research indicates that shiftwork may be associated with increased risks of adverse health outcomes, including some cancers. However, the evidence of an association between shiftwork and colorectal cancer risk is limited and inconclusive. Further, while several possible pathways through which shiftwork might result in cancer have been proposed, few studies have taken these factors into account. We investigated the association between two types of shiftwork (graveyard shiftwork and early-morning shiftwork) and six mechanistic shiftwork variables (including light at night and phase shift) and the risk of colorectal cancer among females in an Australian population-based case–control study. Graveyard shiftwork was the primary exposure of interest. Methods Participants (350 cases and 410 controls) completed a lifetime occupational history, and exposure to each of the eight shiftwork variables was assigned to participants through a job exposure matrix. We used logistic regression to calculate odds ratios (OR) and corresponding 95% confidence intervals (CI) for the association between different shiftwork variables and the risk of colorectal cancer, adjusting for potential demographic, lifestyle and medical confounders. Results Working in an occupation involving long-term exposure (>7.5 years) to graveyard shiftwork was not associated with colorectal cancer risk (adjusted OR 0.95, 95% CI 0.57 to 1.58). Similarly, no increased risks of colorectal cancer were seen for any of the other seven shiftwork variables examined. Conclusions No evidence of an increased risk of colorectal cancer among females who had worked in occupations involving shiftwork was observed in this study.

Latex glove use among healthcare workers in Australia

HighlightsLatex gloves were used by 22% of Australian workers.Occupations with the highest use of latex gloves included carers and hairdressers.63% of healthcare workers used latex gloves, and 26% wore powdered latex gloves.Latex gloves were more commonly used by healthcare workers in micro companies.Latex exposure in healthcare workers contributed 3% of the asthma‐related burden. Background: Exposure to natural rubber latex, primarily through the use of gloves, is a well‐recognized cause of occupational asthma. We investigated latex glove use among Australian workers and estimated the resultant burden of occupational asthma among healthcare workers (HCWs). Methods: Data were collected in 2014 as part of the Australian Work Exposures Study‐Asthma, a telephone survey investigating the prevalence of current occupational exposure to asthmagens, including latex. We estimated adjusted prevalence ratios (aPRs) to determine variables associated with the use of latex gloves among HCWs and calculated the asthma‐related disability‐adjusted life years due to latex exposure among HCWs. Results: Latex gloves were used by 22% of respondents. Almost two‐thirds (63%) of HCWs reported wearing latex gloves, with 26% using powdered latex gloves. The use of latex gloves was more common among those employed in micro companies (less than 5 employees) than large companies (200+ employees) (aPR = 1.5, 95% confidence interval 1.1‐2.0). Latex exposure in HCWs was estimated to contribute 3% of the total asthma‐related burden. Discussion: Latex gloves are widely used by Australian workers and by HCWs in particular. Conclusions: This is the first estimate of the burden of asthma attributable to occupational exposure to latex among HCWs. These results can be used to guide decisions regarding the control of occupational exposure to latex.

Occupational exposure to carcinogens in Australian road transport workers.

BACKGROUND Road transport workers (RTWs) are at high risk of exposure to several occupational carcinogens. However, there are gaps in knowledge regarding the extent and the circumstances of exposure. As a sub-study of the Australian Work Exposures Study, this study investigated the prevalence of occupational exposure in Australian RTWs. METHODS A random sample of Australian working population was invited to a telephone interview regarding their current jobs. An automated expert-assessment procedure was applied to self-reported job-related tasks using a web-based application. 162 RTWs were included in this study. RESULTS RTWs were exposed to diesel exhaust (97%), solar ultraviolet radiation (78%), environmental tobacco smoke (55%), benzene (29%), silica (15%), and asbestos (10%) at work. Besides driving on roads, vehicle maintenance-related tasks were the major source of carcinogen exposures among RTWs. DISCUSSION Most RTWs are exposed to at least one carcinogen at work. We have identified tasks where the use of control measures could potentially reduce exposures.

Isocyanates in Australia: Current exposure to an old hazard

ABSTRACT Exposure to isocyanates has consistently been reported as the most common cause of occupational asthma. The objectives of this study were to assess how many Australian workers are currently exposed to isocyanates, identify the occupations with highest proportion of exposed workers and identify the main circumstances of exposures. Data comes from the Australian Workplace Exposure Study-Asthma, a national telephone survey which explored the prevalence of current occupational exposure to 227 asthmagens, grouped into 27 groups, among current Australian workers aged 18–65 years. A web-based tool, OccIDEAS, was used to collect job task information and to assign exposure to asthmagens, including isocyanates. Of the 4,878 eligible participants, 2.5% of them were deemed to be probably exposed to isocyanates at work in their current job (extrapolated to 3.0% of the Australian working population). The majority of those exposed were males (90.8%). The most common tasks undertaken that led to these exposures were using expanding foam fillers/sprays and isocyanate and/or polyurethane paints. Exposure occurred mainly among construction workers, wood workers, and painters or printers. This study investigating occupational exposure to isocyanates in a national working population provides information that can be used to inform the direction of occupational interventions and policies to decrease occupational asthma.

Prevalence and Outcomes of Undiagnosed Peripheral Arterial Disease Among High Risk Patients in Australia: An Australian REACH Sub-Study

BACKGROUND Compared with other manifestations of cardiovascular disease, peripheral arterial disease (PAD) is under-diagnosed. This study aims to investigate the prevalence, risk profile and cardiovascular outcomes of undiagnosed PAD in Australian general practices. METHOD A sub-study of the Australian Reduction of Atherothrombosis for Continued Health (REACH) Registry, a prospective cohort study of patients at high risk of atherothrombosis recruited from Australian general practices. Eligible patients for this study had no previous clinical diagnosis of PAD and had an ankle-brachial index (ABI) ≤1.4 at recruitment. RESULTS Peripheral arterial disease was undiagnosed in 34% Australian REACH participants, 28% patients had low ABI (ABI<0.9) and 11% had intermittent claudication (IC) based on responses to the Edinburgh Claudication Questionnaire (ECQ). We found no significant differences in risk factor control between patient with or without PAD. Intermittent claudication patients had higher risks of non-fatal cardiovascular events and PAD interventions at one year, whereas all-cause mortality rate was higher among patients with ABI<0.9, especially in those who also reported IC. Finally, an ABI<0.9, together with poorly controlled risk factors were independent predictors of incident IC at one year. CONCLUSIONS This study suggests a high rate of undiagnosed PAD among high risk patients in Australian primary health care. These patients are at high risk of events and therefore would potentially benefit from better secondary prevention measures.

Variations in mesothelioma mortality rates among migrants to Australia and Australian-born

ABSTRACT Background: Australia’s use and consumption of asbestos occurred at the same time as its immigration boom. Our objective was to investigate mesothelioma death rates among migrants and Australian-born between 1981 and 2012. Methods: Australian national mesothelioma deaths from 1981 to 2002 and 2006 to 2012 together with national censuses from 1981 to 2011 were extracted and combined. Directly standardised rates and negative binomial regression were applied examining differences in mesothelioma death rates with regard to country of birth. Results: Migrants from the UK and Ireland, Italy and Germany had significantly higher mesothelioma death rates than Australian-born; lower rates were observed among migrants from other countries. Conclusions: Our findings suggest there may have been differences in occupational health and safety between foreign and Australian-born. Because of changes in the demographics of migrants to Australia since the 1970s and changes in occupational circumstances over time, further comparisons of occupational-related health outcomes between foreign and Australian-born could identify potential occupational inequalities that may still exist today.

The prevalence of exposure to high molecular weight asthmagens derived from plants among workers in Australia

BACKGROUND Limited information is available on exposure to high molecular weight (HMW) asthmagens derived from plants and on the main occupations and tasks that result in such exposure among workers. METHODS Data were collected as part of the Australian Work Exposures Study-Asthma. We estimated adjusted prevalence ratios (aPR) using modified Poisson regression models to determine which factors were associated with exposure. RESULTS A 12.8% of 4878 workers were exposed to HMW asthmagens derived from plants. The highest prevalence of exposure was found among farmers/animal workers, education workers, and food processing workers. The main circumstances of exposure were through handling flour, freesias, or through raising livestock. Exposure was more common among female workers (aPR = 1.26, 1.10-1.43) than males, while it was lower among workers born overseas (aPR = 0.70, 0.57-0.86) than those born in Australia. CONCLUSION Prevention of exposure to HMW asthmagens derived from plants requires a broad strategy targeting different tasks and occupations.