Occupation as socioeconomic status or environmental exposure? A survey of practice among population-based cardiovascular studies in the United States

Occupational inequalities in mortality from cardiovascular disease, 2020-2021

BACKGROUND

In recent years previous declines in cardiovascular disease (CVD) have stalled. There are occupational risk factors for CVD mortality. This study seeks to examine inequalities in CVD mortality for working-age adults in the United States by occupation.

METHODS

Death certificate data for CVD deaths were obtained from the National Center for Health Statistics. Occupation data from these death certificates were coded to major occupation groups. Using information about the number of workers employed in these occupations obtained from the American Community Survey, we calculated mortality rates and rate ratios (RRs), adjusted for covariates associated with CVD mortality.

RESULTS

After adjusting for age, sex, race/ethnicity, and educational attainment, workers in 11 occupations had significantly elevated RRs: food preparation and serving; construction and extraction; arts, design, entertainment, sports, and media; life, physical, and social science; farming, fishing, and forestry; legal; protective services; building and grounds cleaning and maintenance; healthcare practitioners and technical; personal care and service; and community and social services.

CONCLUSIONS

Occupation appears to be a significant predictor of CVD mortality. Further research is needed to assess how occupational risk factors contribute to changing trends for CVD mortality. Interventions are needed to address workplace risk factors for CVD.

Assessing the role of social determinants of health in health disparities: The need for data on work

BACKGROUND

Work is a key social determinant of health. Without the collection of work-related information in public health data systems, the role of social determinants in creating and reinforcing health disparities cannot be fully assessed.

METHODS

The Centers for Disease Control and Prevention (CDC) maintains or supports a number of public health surveillance and health monitoring systems, including surveys, case-based disease and exposure systems, vital status records, and administrative data systems. We evaluated a convenience sample of these systems for inclusion of information in three work-related domains: employment status, industry and occupation, and working conditions.

RESULTS

While 12 of 39 data systems were identified as collecting work-related data, this information was often minimal (e.g., only employment status), restricted to a subset of respondents, or only gathered periodically. Information on working conditions was particularly sparse.

CONCLUSION

Historically, the limited and inconsistent collection of work-related information in public health data systems has hindered understanding of the role work plays in health disparities. Current CDC data modernization efforts present opportunities to enhance the identification and mitigation of health disparities by prioritizing inclusion of an expanded set of work-related data elements.

Perceived health inequalities: are the UK and US public aware of occupation-related health inequality, and do they wish to see it reduced?

BACKGROUND

One underexamined factor in the study of lay views of socioeconomic health inequalities is occupation-related health. Examining health by occupational social class has a long history in the UK but has been comparatively overlooked in US public health literatures, where the relationship between health and work has attended more to hazard exposure.

METHODS

Representative samples of the UK and US indicated the perceived and ideal lifespan of people working in "higher managerial/professional" and "routine" occupations. We examine perceptions of inequality and desires for equality across occupation groups as a function of country and key socio-demographic variables.

RESULTS

67.8% of UK and 53.7% of US participants identified that professionals live longer than routine workers. Multivariate models indicated that US participants were markedly less likely to be aware of occupation-related inequalities after controlling for age, gender, and education. Awareness was negatively related to age (in the US) and recent voting behaviours (both samples). Desiring equal life expectancy was less likely in the US sample, and less likely across both samples among older participants and those with lower levels of education.

CONCLUSION

Employing a novel approach to measuring perceived and ideal life expectancy inequality, this is the first study to examine perceptions of lifespan inequality by occupational groups. It reports widespread understanding of the occupation-related gradient in lifespan and a desire that these inequalities be eliminated in the UK, but considerably less awareness and desire for equality in the US. Greater tolerance for social status inequalities in the US than other similar countries appear to also extend to differences in life expectancy.

Socioeconomic Status, Occupational Disease, and Psychological Well-Being: Evidence from People with Pneumoconiosis in China

Background: Pneumoconiosis is one of the most prevalent occupational diseases in China. The present study aims to examine the status, needs, and challenges of people with pneumoconiosis from a socioeconomic perspective and to reveal the mechanisms by which the disease is linked to their psychological well-being. This study also examines the association of the social security subsidy to such mechanism. Methods: A questionnaire survey of 1134 respondents from seven cities or districts in China was conducted from 2014 to 2016. Generalized Structural Equation Modeling (GSEM) was employed to complete the analysis using Stata 16. Results: Respondents with poor socioeconomic status engaged longer in dusty work and had higher stages of pneumoconiosis, complications, and aggravation. These, in turn, were linked to their socioeconomic status due to high treatment expenditure and loss of the ability to work, which were negatively associated with their psychological well-being. Social security assistance and subsidies could help improve their socioeconomic status. Conclusions: This study provides evidence for the mechanism of social factors linking to physical health and further to psychological well-being among people with pneumoconiosis. Social security assistance and subsidies should be urgently provided for them to improve their socioeconomic status and their psychological well-being.

Socioeconomic disparities in asthma health care utilization, exacerbations, and mortality: A systematic review and meta-analysis

BACKGROUND

Prior studies investigating the effect of socioeconomic status (SES) on asthma health care outcomes have been heterogeneous in the populations studied and methodologies used.

OBJECTIVE

We sought to systematically synthesize evidence investigating the impact of SES on asthma health care utilization, exacerbations, and mortality.

METHODS

We searched Embase, Medline, and Web of Science for studies reporting differences in primary care attendance, exacerbations, emergency department attendance, hospitalization, ventilation/intubation, readmission, and asthma mortality by SES. Study quality was assessed using the Newcastle Ottawa Scale, and meta-analyses were conducted using random-effects models. We conducted several prespecified subgroup analyses, including by health care system (insurance based vs universal government funded) and time period (before vs after 2010).

RESULTS

A total of 61 studies, comprising 1,145,704 patients, were included. Lower SES was consistently associated with increased secondary health care utilization including emergency department attendance (odds ratio [OR], 1.61; 95% confidence interval [CI], 1.40-1.84), hospitalization (OR, 1.63; 95% CI, 1.34-1.99), and readmission (OR, 1.31; 95% CI, 1.19-1.44). Substantial associations were also found between SES and ventilation/intubation (OR, 1.76; 95% CI, 1.13-2.73), although there was no association with primary care attendances (OR, 0.79; 95% CI, 0.51-1.24). We found evidence of borderline significance for increased exacerbations (OR, 1.18; 95% CI, 0.98-1.42) and mortality (OR, 1.12; 95% CI, 0.92-1.37) among more deprived groups. There was no convincing evidence that disparities were associated with country-level health care funding models or that disparities have narrowed over time.

CONCLUSIONS

Patients with a lower SES have substantially increased secondary care health care utilization. We found evidence suggestive of increased exacerbations and mortality risk, although CIs were wide. These disparities have been consistently reported worldwide, including within countries offering universally funded health care systems. Systematic review registration: CRD42020173544.

Occupation Coding of Job Titles: Iterative Development of an Automated Coding Algorithm for the Canadian National Occupation Classification (ACA-NOC)

Background

In many research studies, the identification of social determinants is an important activity, in particular, information about occupations is frequently added to existing patient data. Such information is usually solicited during interviews with open-ended questions such as “What is your job?” and “What industry sector do you work in?” Before being able to use this information for further analysis, the responses need to be categorized using a coding system, such as the Canadian National Occupational Classification (NOC). Manual coding is the usual method, which is a time-consuming and error-prone activity, suitable for automation.

Objective

This study aims to facilitate automated coding by introducing a rigorous algorithm that will be able to identify the NOC (2016) codes using only job title and industry information as input. Using manually coded data sets, we sought to benchmark and iteratively improve the performance of the algorithm.

Methods

We developed the ACA-NOC algorithm based on the NOC (2016), which allowed users to match NOC codes with job and industry titles. We employed several different search strategies in the ACA-NOC algorithm to find the best match, including exact search, minor exact search, like search, near (same order) search, near (different order) search, any search, and weak match search. In addition, a filtering step based on the hierarchical structure of the NOC data was applied to the algorithm to select the best matching codes.

Results

The ACA-NOC was applied to over 500 manually coded job and industry titles. The accuracy rate at the four-digit NOC code level was 58.7% (332/566) and improved when broader job categories were considered (65.0% at the three-digit NOC code level, 72.3% at the two-digit NOC code level, and 81.6% at the one-digit NOC code level).

Conclusions

The ACA-NOC is a rigorous algorithm for automatically coding the Canadian NOC system and has been evaluated using real-world data. It allows researchers to code moderate-sized data sets with occupation in a timely and cost-efficient manner such that further analytics are possible. Initial assessments indicate that it has state-of-the-art performance and is readily extensible upon further benchmarking on larger data sets.

Occupied with classification: Which occupational classification scheme better predicts health outcomes?

Health inequalities continue to grow despite continuous policy intervention. Work, one domain of health inequalities, is often included as a component of social class rather than as a determinant in its own right. Many social class classifications are derived from occupation types, but there are other components within them that mean they may not be useful as proxies for occupation. This paper develops the exposome, a life-course exposure model developed by Wild (2005), into the worksome, allowing for the explicit consideration of both physical and psychosocial exposures and effects derived from work and working conditions. The interactions between and within temporal and geographical scales are strongly emphasised, and the interwoven nature of both psychosocial and physical exposures is highlighted. Individuals within an occupational type can be both affected by and effect upon occupation level characteristics and health measures. By using the worksome, occupation types are separated from value-laden social classifications. This paper will empirically examine whether occupation better predicts health measures from the European Working Conditions Survey (EWCS). Logistic regression models using Bayesian MCMC estimation were run for each classification system, for each health measure. Health measures included, for example, whether the respondent felt their work affected their health, their self-rated health, pain in upper or lower limbs, and headaches. Using the Deviance Information Criterion (DIC), a measure of predictive accuracy penalised for model complexity, the models were assessed against one another. The DIC shows empirically which classification system is most suitable for use in modelling. The 2-digit International Standard Classification of Occupations showed the best predictive accuracy for all measures. Therefore, examining the relationship between health and work should be done with classifications specific to occupation or industry rather than socio-economic class classifications. This justifies the worksome, allowing for a conceptual framework to link many forms of work-health research.

Participation in a US community-based cardiovascular health study: investigating nonrandom selection effects related to employment, perceived stress, work-related stress, and family caregiving

PURPOSE

Participation in health studies may be inversely associated with employment and stress. We investigated whether employment, perceived stress, work-related stress, and family caregiving were related to participation in a longitudinal US community-based health study of black and white men and women aged ≥45 years.

METHODS

Prevalence ratios and confidence intervals were estimated for completion of the second stage (S2) of a two-stage enrollment process by employment (status, type), and stress (perceived stress, work-related stress, caregiving), adjusting for age, sex, race, region, income, and education. Eligibility and consent for a follow-up occupational survey were similarly evaluated.

RESULTS

Wage- but not self-employed participants were less likely than the unemployed to complete S2. Among the employed, S2 completion did not vary by stress; however, family caregivers with a short time burden of care (<2 hour/d) were more likely to complete S2, compared to noncaregivers. Eligibility and participation in the follow-up occupational survey were higher among those employed (vs. unemployed) at enrollment but were not associated with enrollment stress levels.

CONCLUSIONS

Limited evidence of selection bias was seen by employment and stress within a large US community-based cohort, but findings suggest the need for enrollment procedures to consider possible barriers to participation among wage-employed individuals.

Occupational Distribution of Campylobacteriosis and Salmonellosis Cases - Maryland, Ohio, and Virginia, 2014

Campylobacter and Salmonella are leading causes of bacterial gastroenteritis in the United States and are estimated to cause >1 million episodes of domestically acquired illness annually (1). Campylobacter and Salmonella are primarily transmitted through contaminated food, but animal-to-human and human-to-human transmission can also occur (2,3). Although occupationally acquired infections have been reported, occupational risk factors have rarely been studied. In 2015, the Occupational Safety and Health Administration (OSHA) identified 63 suspected or confirmed cases of Campylobacter infection over 3.5 years at a poultry-processing plant (Kathleen Fagan, OSHA, personal communication, December 2015); most involved new workers handling chickens in the "live hang" area where bacterial contamination is likely to be the highest. These findings were similar to those of a previous study of Campylobacter infections among workers at another poultry-processing plant (4). The investigation led to discussions among OSHA, state health departments, and CDC's National Institute for Occupational Safety and Health (NIOSH); and a surveillance study was initiated to further explore the disease incidence in poultry-processing plant workers and identify any additional occupations at increased risk for common enteric infections. Deidentified reports of campylobacteriosis and salmonellosis among Maryland, Ohio, and Virginia residents aged ≥16 years were obtained and reviewed. Each employed patient was classified into one of 23 major occupational groups using the 2010 Standard Occupational Classification (SOC) system.* Risk ratios (RR) and 95% confidence intervals (CI) for associations between each occupational group and each disease were calculated to identify occupations potentially at increased risk, contrasting each group with all other occupations. In 2014, a total of 2,977 campylobacteriosis and 2,259 salmonellosis cases were reported. Among the 1,772 (60%) campylobacteriosis and 1,516 (67%) salmonellosis cases in patients for whom occupational information was available, 1,064 (60%) and 847 (56%), respectively, were employed. Persons in farming, fishing, and forestry as well as health care and technical occupations were at significantly increased risk for both campylobacteriosis and salmonellosis compared with all other occupations. Targeting education and prevention strategies could help reduce disease, and improving the systematic collection of occupational information in disease surveillance systems could provide a better understanding of the extent of occupationally acquired diseases.

Cardiovascular Disease Burden and Socioeconomic Correlates: Findings From the Jackson Heart Study

BACKGROUND

Black persons have an excess burden of cardiovascular disease (CVD) compared with white persons. This burden persists after adjustment for socioeconomic status and other known CVD risk factors. This study evaluated the CVD burden and the socioeconomic gradient of CVD among black participants in the JHS (Jackson Heart Study).

METHODS AND RESULTS

CVD burden was evaluated by comparing the observed prevalence of myocardial infarction, stroke, and hypertension in the JHS at baseline (2000-2004) with the expected prevalence according to US national surveys during a similar time period. The socioeconomic gradient of CVD was evaluated using logistic regression models. Compared with the national data, the JHS age- and sex-standardized prevalence ratios for myocardial infarction, stroke, and hypertension were 1.07 (95% CI, 0.90-1.27), 1.46 (95% CI, 1.18-1.78), and 1.51 (95% CI, 1.42-1.60), respectively, in men and 1.50 (95% CI, 1.27-1.76), 1.33 (95% CI, 1.12-1.57), and 1.43 (95% CI, 1.37-1.50), respectively, in women. A significant and inverse relationship was observed between socioeconomic status and CVD within the JHS cohort. The strongest and most consistent socioeconomic correlate after adjusting for age and sex was income for myocardial infarction (odds ratio: 3.53; 95% CI, 2.31-5.40) and stroke (odds ratio: 3.73; 95% CI, 2.32-5.97), comparing the poor and affluent income categories.

CONCLUSIONS

Except for myocardial infarction in men, CVD burden in the JHS cohort was higher than expected. A strong inverse socioeconomic gradient of CVD was also observed within the JHS cohort.

In-Work Poverty and Self-Rated Health in a Cohort of Working Germans: A Hybrid Approach for Decomposing Within-Person and Between-Persons Estimates of In-Work Poverty Status

In this study, we investigated whether self-rated health (SRH) can be predicted by in-work poverty and how between-persons and within-person differences in the poverty status of people who are working contribute to this relationship. We used a logistic random-effects model designed to test within-person and between-persons differences with data from a nationally representative German sample with 19 waves of data collection (1995-2013) to estimate effects of between-persons and within-person differences in working poverty status on poor SRH. Interactions by age and sex were tested, and models controlled for sociodemographic, socioeconomic, and work-related characteristics. We found significant differences in SRH between individuals with different working poverty status but no evidence that within-person differences in working poverty status are associated with poor SRH. The association between in-work poverty and SRH was significantly stronger for women but did not differ significantly by age. All findings were robust when including sociodemographic, socioeconomic, and working characteristics. In this sample of German adults, we found a polarization of poor SRH between the working nonpoor and the working poor but no causal association of within-person differences in working poverty status with SRH.

Offspring Socioeconomic Status and Parent Mortality Within a Historical Population

Considering a network approach to health determinants, we test the hypothesis that benefits of high socioeconomic status (SES) may be transmitted up the generational ladder from offspring to parents. Studies that examine own SES and own health outcomes, or SES of parents and outcomes of young or adolescent children, are common. Those that investigate SES of offspring and their association with parental health are rare. Employing data from a historical population of individuals extracted from a comprehensive population database that links demographic and vital records across generations, this study tests the hypothesis that higher offspring SES associates with lower parental mortality after controlling for parental SES. The sample includes 29,972 individuals born between 1864 and 1883 whose offspring were born between 1886 and 1920. SES is operationalized using Nam-Powers occupational status scores divided into quartiles and a category for farmers. Models assess mortality risk after age 40. Included is a test for whether effects are proportional across parents who died younger and older. Estimated life expectancies across categories of offspring SES conditioned on parental SES are calculated to illustrate specifically how differences in SES relate to differences in years lived. Results indicate a longevity penalty for those whose offspring have low SES and a longevity dividend for those with high-SES offspring. The influence of offspring attributes on well-being of parents points to fluid and myriad linkages between generations.

Commentary on the contributions and future role of occupational exposure science in a vision and strategy for the discipline of exposure science

Exposure science is a holistic concept without prejudice to exposure source. Traditionally, measurements aimed at mitigating environmental exposures have not included exposures in the workplace, instead considering such exposures to be an internal affair between workers and their employers. Similarly, occupational (or industrial) hygiene has not typically accounted for environmental contributions to poor health at work. Many persons spend a significant amount of their lifetime in the workplace, where they maybe exposed to more numerous chemicals at higher levels than elsewhere in their environment. In addition, workplace chemical exposures and other exogenous stressors may increase epigenetic and germline modifications that are passed on to future generations. We provide a brief history of the development of exposure science from its roots in the assessment of workplace exposures, including an appendix where we detail current resources for education and training in exposure science offered through occupational hygiene organizations. We describe existing successful collaborations between occupational and environmental practitioners in the field of exposure science, which may serve as a model for future interactions. Finally, we provide an integrated vision for the field of exposure science, emphasizing interagency collaboration, the need for complete exposure information in epidemiological studies, and the importance of integrating occupational, environmental, and residential assessments. Our goal is to encourage communication and spur additional collaboration between the fields of occupational and environmental exposure assessment. Providing a more comprehensive approach to exposure science is critical to the study of the "exposome", which conceptualizes the totality of exposures throughout a person's life, not only chemical, but also from diet, stress, drugs, infection, and so on, and the individual response.

Investing in prospective cohorts for etiologic study of occupational exposures

Prospective cohorts have played a major role in understanding the contribution of diet, physical activity, medical conditions, and genes to the development of many diseases, but have not been widely used for occupational exposures. Studies in agriculture are an exception. We draw upon our experience using this design to study agricultural workers to identify conditions that might foster use of prospective cohorts to study other occupational settings. Prospective cohort studies are perceived by many as the strongest epidemiologic design. It allows updating of information on exposure and other factors, collection of biologic samples before disease diagnosis for biomarker studies, assessment of effect modification by genes, lifestyle, and other occupational exposures, and evaluation of a wide range of health outcomes. Increased use of prospective cohorts would be beneficial in identifying hazardous exposures in the workplace. Occupational epidemiologists should seek opportunities to initiate prospective cohorts to investigate high priority, occupational exposures.

Examining occupational health and safety disparities using national data: a cause for continuing concern

BACKGROUND

Occupational status, a core component of socioeconomic status, plays a critical role in the well-being of U.S. workers. Identifying work-related disparities can help target prevention efforts.

METHODS

Bureau of Labor Statistics workplace data were used to characterize high-risk occupations and examine relationships between demographic and work-related variables and fatality.

RESULTS

Employment in high-injury/illness occupations was independently associated with being male, Black, ≤high school degree, foreign-birth, and low-wages. Adjusted fatal occupational injury rate ratios for 2005-2009 were elevated for males, older workers, and several industries and occupations. Agriculture/forestry/fishing and mining industries and transportation and materials moving occupations had the highest rate ratios. Homicide rate ratios were elevated for Black, American Indian/Alaska Native/Asian/Pacific Islanders, and foreign-born workers.

CONCLUSIONS

These findings highlight the importance of understanding patterns of disparities of workplace injuries, illnesses and fatalities. Results can improve intervention efforts by developing programs that better meet the needs of the increasingly diverse U.S. workforce.

Methods and feasibility of collecting occupational data for a large population-based cohort study in the United States: the reasons for geographic and racial differences in stroke study

BACKGROUND

Coronary heart disease and stroke are major contributors to preventable mortality. Evidence links work conditions to these diseases; however, occupational data are perceived to be difficult to collect for large population-based cohorts. We report methodological details and the feasibility of conducting an occupational ancillary study for a large U.S. prospective cohort being followed longitudinally for cardiovascular disease and stroke.

METHODS

Current and historical occupational information were collected from active participants of the REasons for Geographic And Racial Differences in Stroke (REGARDS) Study. A survey was designed to gather quality occupational data among this national cohort of black and white men and women aged 45 years and older (enrolled 2003-2007). Trained staff conducted Computer-Assisted Telephone Interviews (CATI). After a brief pilot period, interviewers received additional training in the collection of narrative industry and occupation data before administering the survey to remaining cohort members. Trained coders used a computer-assisted coding system to assign U.S. Census codes for industry and occupation. All data were double coded; discrepant codes were independently resolved.

RESULTS

Over a 2-year period, 17,648 participants provided consent and completed the occupational survey (87% response rate). A total of 20,427 jobs were assigned Census codes. Inter-rater reliability was 80% for industry and 74% for occupation. Less than 0.5% of the industry and occupation data were uncodable, compared with 12% during the pilot period. Concordance between the current and longest-held jobs was moderately high. The median time to collect employment status plus narrative and descriptive job information by CATI was 1.6 to 2.3 minutes per job. Median time to assign Census codes was 1.3 minutes per rater.

CONCLUSIONS

The feasibility of conducting high-quality occupational data collection and coding for a large heterogeneous population-based sample was demonstrated. We found that training for interview staff was important in ensuring that narrative responses for industry and occupation were adequately specified for coding. Estimates of survey administration time and coding from digital records provide an objective basis for planning future studies. The social and environmental conditions of work are important understudied risk factors that can be feasibly integrated into large population-based health studies.

The contribution of stress to the social patterning of clinical and subclinical CVD risk factors in African Americans: the Jackson Heart Study

It is often hypothesized that psychosocial stress may contribute to associations of socioeconomic position (SEP) with risk factors for cardiovascular disease (CVD). However, few studies have investigated this hypothesis among African Americans, who may be more frequently exposed to stressors due to social and economic circumstances. Cross-sectional data from the Jackson Heart Study (JHS), a large population-based cohort of African Americans, were used to examine the contributions of stressors to the association of SEP with selected cardiovascular (CVD) risk factors and subclinical atherosclerotic disease. Among women, higher income was associated with lower prevalence of hypertension, obesity, diabetes and carotid plaque and lower levels of stress. Higher stress levels were also weakly, albeit positively, associated with hypertension, diabetes, and obesity, but not with plaque. Adjustment for the stress measures reduced the associations of income with hypertension, diabetes and obesity by a small amount that was comparable to, or larger, than the reduction observed after adjustment for behavioral risk factors. In men, high income was associated with lower prevalence of diabetes and stressors were not consistently associated with any of the outcomes examined. Overall, modest mediation effects of stressors were observed for diabetes (15.9%), hypertension (9.7%), and obesity (5.1%) among women but only results for diabetes were statistically significant. No mediation effects of stressors were observed in men. Our results suggest that stressors may partially contribute to associations of SEP with diabetes and possibly hypertension and obesity in African American women. Further research with appropriate study designs and data is needed to understand the dynamic and interacting effects of stressors and behaviors on CVD outcomes as well as sex differences in these effects.

What does "occupation" represent as an indicator of socioeconomic status?: exploring occupational prestige and health

The association between socioeconomic status (SES) and health has been widely documented. However, the role of occupation in this association is not clear because occupation is less often used than income and education as an indicator of SES, especially in the United States. This may be caused by the ambiguity in what occupation represents: both health-enhancing resources (e.g., self-affirmation) and health-damaging hazards (e.g., job stress). SES has two aspects: resources and status. While income and education represent resources and imply status, occupational prestige is an explicit indicator of the social status afforded by one's occupation. Using data from the US General Social Survey in 2002 and 2006 (n = 3151), we examine whether occupational prestige has a significant association with self-rated health independent from other SES indicators (income, education), occupational categories (e.g., managerial, professional, technical, service), and previously established work-related health determinants (job strain, work place social support, job satisfaction). After all covariates were included in the multiple logistic regression model, higher occupational prestige was associated with lower odds of reporting poor/fair self-rated health. We discuss potential mechanisms through which occupational prestige may impact health. Our findings not only suggest multiple ways that occupation is associated with health, but also highlight the utility of occupational prestige as an SES indicator that explicitly represents social standing.

Influence of life-course socioeconomic position on incident heart failure in blacks and whites: the Atherosclerosis Risk in Communities Study

The influence of early-life socioeconomic position (SEP) on incident heart failure in blacks and whites is unknown. The authors examined the relation between early-life SEP and incident, hospitalized heart failure among middle-aged US participants (2,503 black and 8,519 white) in the Atherosclerosis Risk in Communities (ARIC) Study. Early-life SEP indicators assessed included parental education, occupation, and home ownership. From 1987 to 2004, 221 and 537 incident heart failure events were identified in blacks and whites, respectively. In Cox proportional hazards regression, early-life SEP was inversely related to incident heart failure after adjustment for age, gender, and study center (for blacks, hazard ratio (HR) = 1.39, 95% confidence interval (CI): 1.00, 1.95; for whites, HR = 1.32, 95% CI: 1.06, 1.64). Additional adjustment for young and mid-to-older adulthood SEP and established heart failure risk factors attenuated this association towards the null in both blacks and whites. Of the SEP measures, mid-to-older adulthood SEP showed the strongest association with incident heart failure in both blacks (HR = 1.32, 95% CI: 0.90, 1.96) and whites (HR = 1.39, 95% CI: 1.11, 1.75). SEP over the life course is related to the risk of incident heart failure, with SEP later in adulthood having a more prominent role than earlier SEP.

Socioeconomic status and smoking among thai adults: results of the National Thai Food Consumption Survey

The authors examined the relationship between socioeconomic status and smoking in Thai adults. A nationally representative sample of 7858 Thais adults (18 years and older) was surveyed during 2004 to 2005. Four demographic/socioeconomic indicators were examined in logistic models: gender, education, occupational status, and annual household income. Overall, 22.2% of the participants were smokers. Men were more likely to be smokers across all age groups and regions. Compared with nonsmokers, current smokers were less educated, more likely to be employed, but had lower household income. When stratified by gender, education and job levels were strongly associated with smoking prevalence among males. A significant relationship was found between annual household income and smoking. Those who lived under the poverty line were more likely to smoke than persons who lived above the poverty line in both genders. The present study demonstrated that socioeconomic factors, especially education level and occupational class, have a strong influence on smoking behavior in Thai adults.

Shift work and risk factors for cardiovascular disease: a study at age 45 years in the 1958 British birth cohort

This study examined associations between exposure to shift-work and risk factors for cardiovascular disease (CVD) and whether the associations are explained by socio-economic circumstances, occupational factors or health behaviours. Biological risk factors for CVD were measured in 7,839 participants of the 1958 British birth cohort at age 45 years who were in paid employment. Regular (>or=1/week) shift-workers included 46% working evenings (1800-2200), 28% weekends, 13% nights (2200-0400) and 14% early mornings (0400-0700). Adverse levels of several CVD risk factors were found in association with increasing participation in any shift-work. Men regularly working all four shift-work types had increased CVD risk factors of approximately 0.1-0.2 standard deviations (e.g. 0.8 kg/m(2) for body mass index; 1.2 cm for waist circumference) than those not regularly working shifts; for women, there was a positive linear trend for triglyceride levels, but a negative trend for diastolic blood pressure. Separate analyses of shift-work types showed associations primarily for night/morning working rather than evening/weekend working. Men had adverse levels of all CVD risk factors except blood pressure and total-cholesterol in association with night or early morning work and women had adverse triglyceride levels. Adjustment for socioeconomic, occupational factors and health behaviours explained most associations except for adiposity and C-reactive protein. Our results highlight night and early morning working associations with an adverse profile of CVD risk factors, which are partly explained by socioeconomic, other occupational factors and health behaviours.

Surveillance of occupational health disparities: challenges and opportunities

Increasingly, the occupational health community is turning its attention to the effects of work on previously underserved populations, and researchers have identified many examples of disparities in occupational health outcomes. However, the occupational health status of some underserved worker populations is not described due to limitations in existing surveillance systems. As such, the occupational health community has identified the need to enhance and improve occupational health surveillance to describe the nature and extent of disparities in occupational illnesses and injuries (including fatalities), identify priorities for research and intervention, and evaluate trends. This report summarizes the data sources and methods discussed at an April 2008 workshop organized by NIOSH on the topic of improving surveillance for occupational health disparities. We discuss the capability of existing occupational health surveillance systems to document occupational health disparities and to provide surveillance data on minority and other underserved communities. Use of administrative data, secondary data analysis, and the development of targeted surveillance systems for occupational health surveillance are also discussed. Identifying and reducing occupational health disparities is one of NIOSH's priority areas under the National Occupational Research Agenda (NORA).

Work and its role in shaping the social gradient in health

Adults with better jobs enjoy better health: job title was, in fact, the social gradient metric first used to study the relationship between social class and chronic disease etiology, a core finding now replicated in most developed countries. What has been less well proved is whether this correlation is causal, and if so, through what mechanisms. During the past decade, much research has been directed at these issues. Best evidence in 2009 suggests that occupation does affect health. Most recent research on the relationship has been directed at disentangling the pathways through which lower-status work leads to adverse health outcomes. This review focuses on six areas of recent progress: (1) the role of status in a hierarchical occupational system; (2) the roles of psychosocial job stressors; (3) effects of workplace physical and chemical hazard exposures; (4) evidence that work organization matters as a contextual factor; (5) implications for the gradient of new forms of nonstandard or "precarious" employment such as contract and shift work; and (6) emerging evidence that women may be impacted differently by adverse working conditions, and possibly more strongly, than men.

Assessing the contribution of working conditions to socioeconomic disparities in health: a commentary

INTRODUCTION

Occupational health researchers can play a pivotal role in increasing our understanding of the role of physical and psychosocial working conditions in producing socioeconomic health disparities and trends of increasing socioeconomic health disparities, contributing to interventions to reduce such disparities, and helping to improve public education materials on this subject. However, a number of methodological challenges in this field need to be considered.

METHODS

Commentary, including a review of selected studies.

RESULTS/CONCLUSION

Research needs to be guided by models of the associations between social (socioeconomic position (SEP), race/ethnicity, immigration status, and gender) and occupational variables and health, to avoid inappropriate control for confounding, and to specify causal pathways (mediation) and interaction effects. Different approaches to the theory and measurement of SEP also need to be tested.

Do early life exposures explain associations in mid-adulthood between workplace factors and risk factors for cardiovascular disease?

BACKGROUND

Workplace factors (night work, long working hours, psychosocial work stress) have been reported to be associated with increased risk of cardiovascular disease (CVD). We investigated whether (i) workplace factors are associated with CVD risk factors independently of each other, (ii) workplace factors interact, thereby modifying associations and (iii) associations are explained by early life exposures.

METHODS

A total of 7916 employed participants in the 1958 British birth cohort underwent a clinical assessment at age 45 years. Regression analysis was used to examine associations between workplace factors and CVD risk factor levels with adjustment for early life exposures.

RESULTS

Night work was associated with adverse levels of most CVD risk factors. Working > or =48 h/week was positively associated with body mass index (BMI) and waist circumference (WC). Low job control was positively associated with glycosylated haemoglobin (HbA1c) and inflammatory factors, and inversely associated with high-density lipoprotein (HDL)-cholesterol. Low demands were positively associated with systolic blood pressure (SBP), triglycerides and inflammatory factors and inversely associated with HDL-cholesterol. Several associations were weakened when workplace factors were adjusted for each other. Night workers in low-demand jobs had higher BMI [0.78 kg/m(2); 95% confidence interval (CI) 0.35, 1.21], WC (1.49 cm; 0.45, 2.52) and SBP (1.38 mmHg; -0.04, 2.81). HDL was lower for low control plus night work (-0.04 mmol/l; -0.08, -0.01) or long hours (-0.12; -0.18, -0.69). Adjustment for early life exposures explained 30-50% of most associations, e.g. night work/low demands associations reduced by 50% for BMI and WC, and by 39% for SBP.

CONCLUSIONS

Associations between workplace factors and CVD risk factors in mid-adulthood arise in part from social and health disadvantage originating earlier in life.

Invited commentary: the search for preventable causes of cardiovascular disease--whither work?

The incidence and mortality of the major cardiovascular disorders vary sharply by occupation, but this is usually attributed to broad socioeconomic factors; the contributions of physical and psychosocial stressors at work remain obscure or controversial. Review of the ongoing studies of cardiovascular disease in the United States in this issue of the Journal demonstrates that few have either collected sufficient occupational data or used these data in published analyses to address this issue. There are compelling reasons to study this issue, starting with the sheer magnitude of the occupational gradient and disease prevalence. If only 5%-15% prove causally linked to preventable factors, an enormous disease-control opportunity would present itself. Moreover, the most suspect work factors-job stress, fine particulate dust, heat, noise, and shiftwork-are highly prevalent in the US workforce. Thankfully, there is evidence that many of the large ongoing studies are moving toward enhancing their occupational data and using what they have already collected. However, because of the complexity of studying these relations, the better solution is not retrofitting but designing studies in the future that combine de novo the conceptual frameworks and technical skills of occupational and social epidemiologists with those of more biologically focused investigators.