The Experts below are selected from a list of 6057 Experts worldwide ranked by ideXlab platform
Tord Kjellstrom - One of the best experts on this subject based on the ideXlab platform.
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0425 an Occupational Epidemiology model for climate change impact assessment
Occupational and Environmental Medicine, 2017Co-Authors: Tord Kjellstrom, Matthias Otto, Bruno Lemke, Chris Freyberg, David Briggs, Lauren LinesAbstract:Thermal physiology science shows the health threats to workers caused by exposure to heat when doing heavy physical labour. Climate change increases environmental heat levels in most of the world and it is a key issue for climate change and health research. Our model links climate and workforce data (current and predicted) and estimates work capacity loss at individual and population level and related economic loss. The model incorporates climate conditions, population estimates, workforce distributions, heat exposure estimates, exposure-response relationships, and socio-economic impact functions. The basis of the model is Occupational Epidemiology. Much of the data upon which heat stress health risk functions are based comes from thermal physiology laboratory research. While this research has provided valuable information about human function at different heat exposures, the individuals studied are generally not the same mix of ages and physical conditions of typical working populations. Very few published studies have included the quantitative Occupational Epidemiology analysis needed for climate change related health risk assessments. For example, different model settings produce annual moderate intensity work hours lost due to heat (in the shade) by the 2050s at 0.7%–1.6% for USA and 1.1%–3.0% for China. Many of these lost hours will reduce the annual GDP, estimated at 34 trillion USD in the USA and 58 trillion in China (2050). Even a small loss creates many billion USD of economic losses. Our model can identify evidence missing for reducing the uncertainties in impact estimates, which can guide decisions about climate change mitigation and adaptation.
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0412 climate change impacts on Occupational health via workplace heat
Occupational and Environmental Medicine, 2017Co-Authors: Tord Kjellstrom, David H Wegman, Lars Nybo, Andreas Fluoris, Lucka KajfezbogatajAbstract:Climate changes will markedly affect working people as increased heat and extreme weather may directly affect health and indirectly via reduced food access and spread of vector-borne diseases among outdoor workers. The effects will primarily affect low income people in tropical and sub-tropical areas, but Occupational health authorities in all countries need to consider the emerging challenges. A recent EU project (www.HEAT-SHIELD.eu) is dedicated to improving heat resilience in workers, and NIOSH/USA recently (2016) published new guidelines. Considering the theme Eliminating Occupational Disease , a widespread Occupational health threat from climate change will be excessive heat exposure causing ” workplace heat related illnesses ”. This is already a major problem in large parts of the world. A number of aspects of the Occupational health challenges will be presented during this Mini-Symposium. Translating research into action involves broadening existing research/analysis to produce improved ”heat exposure evaluation” and ”Occupational health impact assessment” related to climate change. Research needs to identify remediable conditions and solutions/interventions. This requires a major increase in Occupational Epidemiology studies (including intervention studies), focusing on hot parts of the world. The detrimental health and economic impacts should encourage global and national policies to address climate change mitigation. The Mini-Symposium will consider how to address these needs, and encourage networking among scientists in different fields for future studies. It also aims to engage young scientists in a field which has been overlooked in climate change impact analysis. The HEAT-SHIELD project welcomes cooperation in specific studies and sharing of methodologies.
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s03 1 climate change increases workplace heat stress affecting work capacity and Occupational health including kidney disease and other health outcomes related to heat and dehydration
Occupational and Environmental Medicine, 2016Co-Authors: Tord Kjellstrom, Matthias Otto, Jonathan A Patz, Bruno LemkeAbstract:Climate change leads to increasing temperatures, shifting rainfall patterns and more extreme weather events, which affect Occupational health in many ways. Heat stress at work poses health risks and reduced work capacity, presenting a new and widespread Occupational health challenge due to climate change. Human physiology limits to coping with heat stress are well known, but the links to climate change need further analysis. Occupational health effects include heat exhaustion (reducing work capacity), serious heat stroke (including deaths), dehydration effects on the kidneys, and exacerbation of chronic diseases. Cognitive performance is also affected by heat stress. Physical work significantly adds to heat stress because of internal heat production from muscles. Working people slow down or take frequent breaks (self-pacing) to compensate. As a result, reduced productivity creates economic losses. We compared population based estimates of health impacts of heat stress for selected climate models applied to the four different “Representative Concentration Pathways” of greenhouse gases established by the UN Intergovernmental Panel on Climate Change (IPCC). Serious ambient heat stress conditions currently occur 1–2% of annual daylight hours in hot tropical low altitude countries (e.„g. Nicaragua or Bangladesh), while higher altitude countries (e.„g. Ethiopia) or less hot sub-tropical countries (e.g. Greece) have less than 0.2% hours affected. The “business as usual” pathway creates heat stress risks for 10–20% of annual daylight hours in 2085 in the tropics. The climate change mitigation programs offered at the recent UN Framework Convention on Climate Change (UNFCCC) Paris summit may only halve these risks. In many low income countries the loss of work hours will create substantial reductions of annual GDP. Stricter global climate policies are needed, and Occupational Epidemiology research is essential to develop health impact assessments essential for decision-making to protect millions of working people in vulnerable countries.
David H Wegman - One of the best experts on this subject based on the ideXlab platform.
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0412 climate change impacts on Occupational health via workplace heat
Occupational and Environmental Medicine, 2017Co-Authors: Tord Kjellstrom, David H Wegman, Lars Nybo, Andreas Fluoris, Lucka KajfezbogatajAbstract:Climate changes will markedly affect working people as increased heat and extreme weather may directly affect health and indirectly via reduced food access and spread of vector-borne diseases among outdoor workers. The effects will primarily affect low income people in tropical and sub-tropical areas, but Occupational health authorities in all countries need to consider the emerging challenges. A recent EU project (www.HEAT-SHIELD.eu) is dedicated to improving heat resilience in workers, and NIOSH/USA recently (2016) published new guidelines. Considering the theme Eliminating Occupational Disease , a widespread Occupational health threat from climate change will be excessive heat exposure causing ” workplace heat related illnesses ”. This is already a major problem in large parts of the world. A number of aspects of the Occupational health challenges will be presented during this Mini-Symposium. Translating research into action involves broadening existing research/analysis to produce improved ”heat exposure evaluation” and ”Occupational health impact assessment” related to climate change. Research needs to identify remediable conditions and solutions/interventions. This requires a major increase in Occupational Epidemiology studies (including intervention studies), focusing on hot parts of the world. The detrimental health and economic impacts should encourage global and national policies to address climate change mitigation. The Mini-Symposium will consider how to address these needs, and encourage networking among scientists in different fields for future studies. It also aims to engage young scientists in a field which has been overlooked in climate change impact analysis. The HEAT-SHIELD project welcomes cooperation in specific studies and sharing of methodologies.
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0025 conducting global Occupational Epidemiology research in a changing socio political climate case study of research among shanghai china textile workers
Occupational and Environmental Medicine, 2017Co-Authors: Harvey Checkoway, David C Christiani, David H WegmanAbstract:There is a long and continuing legacy of epidemiologists from high income countries conducting Occupational health research in low and middle income countries. Opportunities to investigate Occupational hazards in relatively high exposure settings and to develop multi-country research partnerships that can lead to disease prevention globally are the main motivations for this type of research. However, it should be appreciated that changes in the cultural, economic, and political environment of the country where the research is conducted can have profound influences on the likelihood of research success. Our research groups have long histories of conducting epidemiologic investigations among textile workers in Shanghai, China. The research includes studies of multiple different cancers and parkinsonism (HC) and respiratory disorders (DCC) in relation to exposures to textile industry dusts and chemicals. Several gene/environment investigations have also been conducted. We present the historical background leading to the research, and the logistical challenges that have emerged over time as political, social, and economic conditions in Shanghai have changed. These challenges include reduced access to workplaces, reduced worker participation rates, and governmentally imposed restrictions on transporting bio-specimens outside of China. Based on our experiences, we can offer some recommendations that Occupational epidemiologists in high and low/middle income countries might consider to facilitate collaborative research: being cognizant of national and regional political, social, and economic policy changes; maintaining flexibility in research protocols and budgetary allocations during the course of study conduct; and, keeping lines of communication open throughout the research design and implementation.
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challenges for Occupational Epidemiology in the 21st century observations and opportunities
Occupational and Environmental Medicine, 2014Co-Authors: David H WegmanAbstract:The 2014 International Epidemiology in Occupational Health (EPICOH) meeting in Chicago, USA, focused on the theme: ‘Challenges for Occupational Epidemiology in the 21st Century’. These are exciting times and with them come no end to challenges faced by Occupational Epidemiology. And participants eagerly engaged in vigorous discussion on a number of current concerns with both wisdom and wit. Ultimately each individual must decide what challenges are most important and how best to address those selected for first order attention. Nonetheless, some overview of challenges could prove worthwhile and so six general areas are provided as a focus for consideration. We always run the risk of studying what we know how to study rather than investigating important problems. We must try our best to tackle broad issues and not restrict ourselves to narrow expressions or concerns. To paraphrase Walter Holland1: Overall the number of conditions and environments studied by Occupational epidemiologists needs to be expanded and we must not hesitate to press for resources to investigate and control conditions of little concern to political or commercial interests, but which are of importance to our workers and our societies. Funding for our studies is increasingly difficult but the more important the problem the more likely we can gain the attention of potential funders. It is likely that each of us has a somewhat different view of what are the important problems. One that deserves priority attention is the impact of climate change on the global workforce. There is a remarkably diverse mix of Occupational sectors that will bear the consequences of climate change.2 The numbers of workers potentially affected certainly is in the millions, …
Bruno Lemke - One of the best experts on this subject based on the ideXlab platform.
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0425 an Occupational Epidemiology model for climate change impact assessment
Occupational and Environmental Medicine, 2017Co-Authors: Tord Kjellstrom, Matthias Otto, Bruno Lemke, Chris Freyberg, David Briggs, Lauren LinesAbstract:Thermal physiology science shows the health threats to workers caused by exposure to heat when doing heavy physical labour. Climate change increases environmental heat levels in most of the world and it is a key issue for climate change and health research. Our model links climate and workforce data (current and predicted) and estimates work capacity loss at individual and population level and related economic loss. The model incorporates climate conditions, population estimates, workforce distributions, heat exposure estimates, exposure-response relationships, and socio-economic impact functions. The basis of the model is Occupational Epidemiology. Much of the data upon which heat stress health risk functions are based comes from thermal physiology laboratory research. While this research has provided valuable information about human function at different heat exposures, the individuals studied are generally not the same mix of ages and physical conditions of typical working populations. Very few published studies have included the quantitative Occupational Epidemiology analysis needed for climate change related health risk assessments. For example, different model settings produce annual moderate intensity work hours lost due to heat (in the shade) by the 2050s at 0.7%–1.6% for USA and 1.1%–3.0% for China. Many of these lost hours will reduce the annual GDP, estimated at 34 trillion USD in the USA and 58 trillion in China (2050). Even a small loss creates many billion USD of economic losses. Our model can identify evidence missing for reducing the uncertainties in impact estimates, which can guide decisions about climate change mitigation and adaptation.
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s03 1 climate change increases workplace heat stress affecting work capacity and Occupational health including kidney disease and other health outcomes related to heat and dehydration
Occupational and Environmental Medicine, 2016Co-Authors: Tord Kjellstrom, Matthias Otto, Jonathan A Patz, Bruno LemkeAbstract:Climate change leads to increasing temperatures, shifting rainfall patterns and more extreme weather events, which affect Occupational health in many ways. Heat stress at work poses health risks and reduced work capacity, presenting a new and widespread Occupational health challenge due to climate change. Human physiology limits to coping with heat stress are well known, but the links to climate change need further analysis. Occupational health effects include heat exhaustion (reducing work capacity), serious heat stroke (including deaths), dehydration effects on the kidneys, and exacerbation of chronic diseases. Cognitive performance is also affected by heat stress. Physical work significantly adds to heat stress because of internal heat production from muscles. Working people slow down or take frequent breaks (self-pacing) to compensate. As a result, reduced productivity creates economic losses. We compared population based estimates of health impacts of heat stress for selected climate models applied to the four different “Representative Concentration Pathways” of greenhouse gases established by the UN Intergovernmental Panel on Climate Change (IPCC). Serious ambient heat stress conditions currently occur 1–2% of annual daylight hours in hot tropical low altitude countries (e.„g. Nicaragua or Bangladesh), while higher altitude countries (e.„g. Ethiopia) or less hot sub-tropical countries (e.g. Greece) have less than 0.2% hours affected. The “business as usual” pathway creates heat stress risks for 10–20% of annual daylight hours in 2085 in the tropics. The climate change mitigation programs offered at the recent UN Framework Convention on Climate Change (UNFCCC) Paris summit may only halve these risks. In many low income countries the loss of work hours will create substantial reductions of annual GDP. Stricter global climate policies are needed, and Occupational Epidemiology research is essential to develop health impact assessments essential for decision-making to protect millions of working people in vulnerable countries.
Harvey Checkoway - One of the best experts on this subject based on the ideXlab platform.
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occupation and parkinson disease in women s health initiative observational study
bioRxiv, 2019Co-Authors: Igor Burstyn, Andrea Z Lacroix, Irene Litvan, Robert B Wallace, Harvey CheckowayAbstract:Introduction: There is a lack of consistency in associations between workplace factors and risk of Parkinson disease (PD), and paucity of such data on women. We took a classic Occupational Epidemiology approach that assesses associations with Occupational groups in order to derive insights about potential occupation-specific exposures that may be causal. Methods: The Women9s Health Initiative (WHI-OS) is a prospective cohort that enrolled 91,627 postmenopausal women, 50 to 79 years of age from 10/01/93 to 12/31/98, at 40 clinical centers across the US with average follow-up of 11 years, who reported up to three paid jobs held the longest since age 18; these jobs were coded and duration of employment calculated. We defined the case by self-report of doctor-diagnosed PD (at baseline or follow-up), death attributed to PD, or medication consistent with PD. Results: Among 2,590 cases, we report evidence of excess risk among "counselors, social workers, and other community and social service specialists". There was a suggestion of increase in risk among post-secondary teachers, and "building and grounds cleaning and maintenance". There was also evidence of deficit in risk among women who worked in sales. Results with ever-employed and duration were similar, except for evidence of excess of risk among "health technologists and technicians" with more than 20 years of employment. Longer duration of life on a farm was associated with higher risk. Conclusion: Our findings paint a largely reassuring picture of Occupational risks for PD among US women, especially for trades largely unaffected by recent technological advances.
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0025 conducting global Occupational Epidemiology research in a changing socio political climate case study of research among shanghai china textile workers
Occupational and Environmental Medicine, 2017Co-Authors: Harvey Checkoway, David C Christiani, David H WegmanAbstract:There is a long and continuing legacy of epidemiologists from high income countries conducting Occupational health research in low and middle income countries. Opportunities to investigate Occupational hazards in relatively high exposure settings and to develop multi-country research partnerships that can lead to disease prevention globally are the main motivations for this type of research. However, it should be appreciated that changes in the cultural, economic, and political environment of the country where the research is conducted can have profound influences on the likelihood of research success. Our research groups have long histories of conducting epidemiologic investigations among textile workers in Shanghai, China. The research includes studies of multiple different cancers and parkinsonism (HC) and respiratory disorders (DCC) in relation to exposures to textile industry dusts and chemicals. Several gene/environment investigations have also been conducted. We present the historical background leading to the research, and the logistical challenges that have emerged over time as political, social, and economic conditions in Shanghai have changed. These challenges include reduced access to workplaces, reduced worker participation rates, and governmentally imposed restrictions on transporting bio-specimens outside of China. Based on our experiences, we can offer some recommendations that Occupational epidemiologists in high and low/middle income countries might consider to facilitate collaborative research: being cognizant of national and regional political, social, and economic policy changes; maintaining flexibility in research protocols and budgetary allocations during the course of study conduct; and, keeping lines of communication open throughout the research design and implementation.
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0137 exposure lag response in Occupational Epidemiology application of distributed non linear lag models in a cohort of diatomaceous earth workers exposed to crystalline silica
Occupational and Environmental Medicine, 2017Co-Authors: Andreas M Neophytou, Harvey Checkoway, Ellen A Eisen, Daniel M Brown, Sally Picciotto, Sadie CostelloAbstract:Occupational exposures extending over a long working life can have complex relationships with health outcomes, as timing, duration, and intensity of exposure are all potentially relevant. Simple measures of cumulative, or average intensity of exposure typically considered in Occupational studies may not fully capture these relationships. We applied distributed non-linear lag models to examine the association of crystalline silica exposures with mortality from lung cancer and non-malignant respiratory disease. We fitted Cox proportional hazard models for each cause of interest to data from a cohort study of 2342 California diatomaceous earth workers exposed to crystalline silica. Our models combined various functions for exposure-response and lag-response including linear, piece-wise constant and spline functions. Models with a spline function for exposure-response and a constant term for the lag-response appeared to have the best fit for lung cancer, while models with spline functions for both exposure-response and lag-response had the best fit for non-malignant respiratory disease. Hazard ratios (HR) from these best fitting models corresponding to average daily exposures of 275 µg/m3 during lag years 11–40 prior to the age of observed cases were 1.96 (95% confidence interval (CI) 0.95–4.06) and 2.01 (95% CI: 1.02–3.97) for the two outcomes respectively. HRs from simple models with linear exposure-response and constant lag-response terms for the same exposure scenario were 1.15 (95% CI: 0.88–1.49) and 1.21 (95% CI: 1.01–1.44) respectively. Occupational studies of longitudinal cohorts with detailed exposure histories could benefit from methods allowing for non-linearities and the disentanglement of intensity, duration and timing of exposure.
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future needs of Occupational Epidemiology of extremely low frequency electric and magnetic fields review and recommendations
Occupational and Environmental Medicine, 2008Co-Authors: Leeka Kheifets, Harvey Checkoway, Joseph D Bowman, Maria Feychting, John Harrington, Robert Kavet, Gary M Marsh, Gabor Mezei, David Renew, E Van WijngaardenAbstract:The Occupational epidemiological literature on extremely low frequency electric and magnetic fields (EMF) and health encompasses a large number of studies of varying design and quality that have addressed many health outcomes, including various cancers, cardiovascular disease, depression and suicide, and neurodegenerative diseases, such as Alzheimer disease and amyotrophic lateral sclerosis (ALS). At a 2006 workshop we reviewed studies of Occupational EMF exposure with an emphasis on methodological weaknesses, and proposed analytical ways to address some of these. We also developed research priorities that we hope will address remaining uncertainties. Broadly speaking, extensive epidemiological research conducted during the past 20 years on Occupational EMF exposure does not indicate strong or consistent associations with cancer or any other health outcomes. Inconsistent results for many of the outcomes may be attributable to numerous shortcomings in the studies, most notably in exposure assessment. There is, however, no obvious correlation between exposure assessment quality and observed associations. Nevertheless, for future research, the highest priorities emerge in both the areas of exposure assessment and investigation of ALS. To better assess exposure, we call for the development of a more complete job-exposure matrix that combines job title, work environment and task, and an index of exposure to electric fields, magnetic fields, spark discharge, contact current, and other chemical and physical agents. For ALS, we propose an international collaborative study capable of illuminating a reported association with electrical occupations by disentangling the potential roles of electric shocks, magnetic fields and bias. Such a study will potentially lead to evidence-based measures to protect public health.
Ellen A Eisen - One of the best experts on this subject based on the ideXlab platform.
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0137 exposure lag response in Occupational Epidemiology application of distributed non linear lag models in a cohort of diatomaceous earth workers exposed to crystalline silica
Occupational and Environmental Medicine, 2017Co-Authors: Andreas M Neophytou, Harvey Checkoway, Ellen A Eisen, Daniel M Brown, Sally Picciotto, Sadie CostelloAbstract:Occupational exposures extending over a long working life can have complex relationships with health outcomes, as timing, duration, and intensity of exposure are all potentially relevant. Simple measures of cumulative, or average intensity of exposure typically considered in Occupational studies may not fully capture these relationships. We applied distributed non-linear lag models to examine the association of crystalline silica exposures with mortality from lung cancer and non-malignant respiratory disease. We fitted Cox proportional hazard models for each cause of interest to data from a cohort study of 2342 California diatomaceous earth workers exposed to crystalline silica. Our models combined various functions for exposure-response and lag-response including linear, piece-wise constant and spline functions. Models with a spline function for exposure-response and a constant term for the lag-response appeared to have the best fit for lung cancer, while models with spline functions for both exposure-response and lag-response had the best fit for non-malignant respiratory disease. Hazard ratios (HR) from these best fitting models corresponding to average daily exposures of 275 µg/m3 during lag years 11–40 prior to the age of observed cases were 1.96 (95% confidence interval (CI) 0.95–4.06) and 2.01 (95% CI: 1.02–3.97) for the two outcomes respectively. HRs from simple models with linear exposure-response and constant lag-response terms for the same exposure scenario were 1.15 (95% CI: 0.88–1.49) and 1.21 (95% CI: 1.01–1.44) respectively. Occupational studies of longitudinal cohorts with detailed exposure histories could benefit from methods allowing for non-linearities and the disentanglement of intensity, duration and timing of exposure.
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marginal structural models in Occupational Epidemiology application in a study of ischemic heart disease incidence and pm2 5 in the us aluminum industry
American Journal of Epidemiology, 2014Co-Authors: Andreas M Neophytou, Mark R Cullen, Sadie Costello, Elizabeth M Noth, Daniel M Brown, Sally Picciotto, Katharine S Hammond, Ellen A EisenAbstract:Marginal structural models (MSMs) and inverse probability weighting can be used to estimate risk in a cohort of active workers if there is a time-varying confounder (e.g., health status) affected by prior exposure-a feature of the healthy worker survivor effect. We applied Cox MSMs in a study of incident ischemic heart disease and exposure to particulate matter with aerodynamic diameter of 2.5 μm or less (PM2.5) in a cohort of 12,949 actively employed aluminum workers in the United States. The cohort was stratified by work process into workers in smelting facilities, herein referred to as "smelters" and workers in fabrication facilities, herein referred to as "fabricators." The outcome was assessed by using medical claims data from 1998 to 2012. A composite risk score based on insurance claims was treated as a time-varying measure of health status. Binary PM2.5 exposure was defined by the 10th-percentile cutoff for each work process. Health status was associated with past exposure and predicted the outcome and subsequent exposure in smelters but not in fabricators. In smelters, the Cox MSM hazard ratio comparing those always exposed above the cutoff with those always exposed below the cutoff was 1.98 (95% confidence interval: 1.18, 3.32). In fabricators, the hazard ratio from a traditional Cox model was 1.34 (95% confidence interval: 0.98, 1.83). Results suggest that Occupational PM2.5 exposure increases the risk of incident ischemic heart disease in workers in both aluminum smelting and fabrication facilities.
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0223 marginal structural models in Occupational Epidemiology an application in the us aluminium industry
Occupational and Environmental Medicine, 2014Co-Authors: Andreas M Neophytou, Mark R Cullen, Sadie Costello, Elizabeth M Noth, Katharine Hammond, Daniel S Brown, Ellen A EisenAbstract:Objectives To apply Marginal Structural Models (MSM) to address healthy workers survivor effect in a cohort study of active workers when time varying variables on health status and exposure are measured. Method We used Cox MSMs and inverse probability weighting to assess the effect of PM 2.5 exposure on incident ischaemic heart disease (IHD) in an active cohort of 11 966 US aluminium workers. The outcome was assessed using medical claims data from 1998 to 2012. Quantitative exposure metrics of current exposure to PM 2.5 were dichotomized using different cutoffs and effects were assessed separately for smelters and fabrication. Risk score based on insurance claims was available as a time varying health status variable. Results Defining binary PM2.5 exposure by the 10th percentile cut-off, health status was affected by past exposure and predicted subsequent exposure in smelters, but not in fabrication. A Traditional cox model was appropriate for fabricators; the hazard ratio was 1.51(95% CI: 1.12 – 2.06) and was attenuated when considering higher exposure cutoffs. In smelters, Cox MSM Hazard Ratios for IHD comparing the effect of exposure in a population had everyone always been exposed to everyone always unexposed, using the 10 th percentile exposure cutoff was 1.83 (95% CI: 1.14 – 2.94). Higher exposure cutoffs also resulted in attenuated effects. Conclusions Marginal Structural Models can be used in active employment Occupational cohorts to address time varying confounding. Results from the current study suggest that Occupational exposure to PM 2.5 in the aluminium industry increases the risk of IHD in both smelters and fabrication.
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smoothing in survival models an application to workers exposed to metalworking fluids
Epidemiology, 2002Co-Authors: Sally W Thurston, Ellen A Eisen, Joel SchwartzAbstract:Background. In Occupational Epidemiology it is typically assumed that the relation between exposure, possibly transformed, and the risk of an adverse health outcome is linear in the parameters. Alternatively, exposure is transformed into a categorical variable.Methods. We used nonparametric regressi
