Occupational Exposure to Vapor-Gas, Dust, and Fumes in a Cohort of Rural Adults in Iowa Compared with a Cohort of Urban Adults

The association of forced expiratory volume in one second with occupational exposures in a longitudinal study of adults in a rural community in Iowa

PURPOSE

The Keokuk County Rural Health Study (KCRHS) is a longitudinal population-based study conducted in rural Iowa. A prior analysis of enrollment data identified an association of airflow obstruction with occupational exposures only among cigarette smokers. The current study used spirometry data from all three rounds to investigate whether level of forced expiratory volume in one second (FEV1) and longitudinal change in FEV1 were associated with occupational vapor-gas, dust, and fumes (VGDF) exposures, and whether these associations were modified by smoking.

METHODS

This study sample comprised 1071 adult KCRHS participants with longitudinal data. A job-exposure matrix (JEM) was applied to participants' lifetime work histories to assign exposures to occupational VGDF. Mixed regression models of pre-bronchodilator FEV1 (millimeters, ml) were fit to test for associations with occupational exposures while adjusting for potential confounders.

RESULTS

Mineral dust had the most consistent association with change in FEV1, including ever/never ( - 6.3 ml/year) and nearly every level of duration, intensity, and cumulative exposure. Because 92% of participants with mineral dust also had organic dust exposure, the results for mineral dust may be due to a combination of the two. An association of FEV1 level with fumes was observed for high intensity ( - 91.4 ml) among all participants, and limited to cigarette smokers with results of  - 104.6 ml ever/never exposed,  - 170.3 ml high duration, and  - 172.4 ml high cumulative.

CONCLUSION

The current findings suggest that mineral dust, possibly in combination with organic dust, and fumes exposure, especially among cigarette smokers, were risk factors for adverse FEV1 results.

Exposure to occupational risk factors is associated with the severity and progression of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) results from a complex interaction between genes and the environment, and occupational exposures are an underappreciated risk factor. Until now, little research attention has been paid to the potential impact of occupational risk factor exposure on the COPD in China. The aim of this retrospective study was to analyze the role of occupational risk factor exposure on the severity and progression of COPD for exploring new prevention strategies for this disease. This study adopted a random cluster-sampling method. Five grade-A tertiary hospitals that met the inclusion criteria were selected as the survey sites, and patients with COPD hospitalized in these hospitals from January 1, 2019, to December 31, 2019, were selected as the research subjects. Data of the patients diagnosed with COPD met the Global Initiative for Chronic Obstructive Lung Disease (2019) criteria and were collected from the computerized medical record databases. Among 4082 investigated COPD patients, 1063 (26%) were found to have occupational risk factor exposure history. The top 3 industries with a large COPD case number and a history of occupational risk factor exposure ranked in the order of agriculture (including farming, forestry, animal husbandry, and fishery), manufacturing, and mining. Further multivariate logistic regression analysis indicated that when setting a low exposure level as a reference, medium and high exposure levels were correlated with the severity of COPD (odds ratio values were 2.837 and 6.201, respectively, P < .05). Linear regression analysis showed that cumulative exposure to occupational risk factors was negatively correlated with the forced expiratory volume in 1-second percentage of COPD patients, with a correlation coefficient of 0.68. Our results indicated that occupational risk factor exposure levels were related to the severity of COPD significantly. The incubation period of COPD in the exposure group was significantly shorter than that in the non-exposure group. To prevent worked-related COPD, special attention and control efforts should be taken to reduce the level of occupational risk factors such as organic dust, irritating chemicals, etc in the work environments, especially in the industries of agriculture, forestry, animal husbandry and fishery, manufacturing, and mining.

The association of chronic bronchitis and airflow obstruction with lifetime and current farm activities in a sample of rural adults in Iowa

OBJECTIVE

Farmers have an increased risk for chronic bronchitis and airflow obstruction. The objective of this study was to investigate the association of these health outcomes with farm activities.

METHODS

We evaluated the Keokuk County Rural Health Study (KCRHS) enrollment data for farm activities and the two health outcomes chronic bronchitis based on self-reported symptoms and airflow obstruction based on spirometry. We used logistic regression to model the health outcomes, yielding an odds ratio (OR) and 95% confidence interval (95% CI) for farm activities while adjusting for potential confounders and other risk factors.

RESULTS

Of the 1234 farmers, 104 (8.4%) had chronic bronchitis, 75 (6.1%) fulfilled the criteria for airflow obstruction, and the two outcomes overlapped by 18 participants. Chronic bronchitis without airflow obstruction (n = 86) had a statistically significant association with crop storage insecticides (OR 3.1, 95% CI 1.6, 6.1) and a low number of years (≤ 3) worked with turkeys (OR 3.3, 95% CI 1.2, 9.4). The latter result should be interpreted with caution because it is based on a small number of cases (n = 5). Airflow obstruction with or without chronic bronchitis (n = 75) was significantly associated with ever working in a hog or chicken confinement setting (OR 2.2, 95% CI 1.0, 4.5).

CONCLUSIONS

These results suggest that work with crop storage insecticides or turkeys may increase the risk for chronic bronchitis and work in hog or chicken confinement may increase the risk for airflow obstruction.

Reimagining Rural: Shifting Paradigms About Health and Well-Being in the Rural United States

Rural health disparities have attracted increased national attention, compelling an expanded focus on rural health research. In this manuscript, we deconstruct the definitions and narratives of "rural" communities and suggest that a paradigm shift is needed that centers the complexity and strength of rural places. We discuss the relevance of health equity frameworks, implementation science, and community-engaged approaches to promote rural well-being. Focusing on rural in its own right will lead to intervention innovations and reinvention with implications beyond rural areas. We conclude with suggestions for research and practice to inspire renewed interest in partnering with rural communities to promote health equity. Expected final online publication date for the Annual Review of Public Health, Volume 43 is April 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Challenges Faced by Rural Primary Care Providers When Caring for COPD Patients in the Western United States

RATIONALE

Rural chronic obstructive pulmonary disease (COPD) patients have worse outcomes and higher mortality compared with urban patients. Reasons for these disparities likely include challenges to delivery of care that have not been explored.

OBJECTIVE

To determine challenges faced by rural primary care providers when caring for COPD patients.

METHODS

Rural primary care providers in 7 primarily western states were asked about barriers they experienced when caring for COPD patients.

RESULTS

A total of 71 rural primary care medical providers completed the survey, of which 51% were physicians and 49% were advanced practice providers (APPs). A total of 61% used Global Initiative for Chronic Obstructive Lung Disease or American Thoracic Society/European Respiratory Society guidelines as an assessment and treatment resource. The presence of multiple chronic conditions and patient failure to recognize and report symptoms were the greatest barriers to diagnose COPD. A total of 89% of providers used spirometry to diagnose COPD, but only 62% were satisfied with access to spirometry. Despite recommendations, 41% of providers never test for alpha-1 antitrypsin deficiency. A total of 87% were comfortable with their ability to assess symptoms, but only 11% used a guideline-recommended assessment tool. Although most providers were satisfied with their ability to treat symptoms and exacerbations, only 66% were content with their ability to prevent exacerbations. Fewer providers were happy with their access to pulmonologists (55%) or pulmonary rehabilitation (37%). Subgroup analyses revealed differences based on provider type (APP versus physician) and location (Colorado and Kansas versus other states), but not on population or practice size.

CONCLUSIONS

Rural providers face significant challenges when caring for COPD patients that should be targeted in future interventions to improve COPD outcomes.

Integration of the preventive medicine specialty in the rural and Tribal public health workforce

The majority of the U.S. American Indian and Alaska Native (AI/AN) population live in rural areas, and are thus disproportionately affected by rural health issues. In addition, the AI/AN population has unique health characteristics resulting from a distinct cultural and sociopolitical history. A public health approach to both rural and Tribal health should include the medical specialty of preventive medicine, a unique physician specialty that combines both direct patient care and public health skills. To best prepare preventive medicine physicians for rural and Tribal practice, medical schools could recruit students from rural and Tribal areas and encourage them to pursue the specialty of preventive medicine. Additionally, preventive medicine residency training programs could establish clinical and public health practicum rotations in rural and Tribal areas, and develop curricula that address rural and Tribal health issues. Currently very few preventive medicine residency programs expressly state a mission to train physicians in rural or Tribal settings.

Association of occupational dust exposure with combined chronic obstructive pulmonary disease and pneumoconiosis: a cross-sectional study in China

OBJECTIVES

Occupational dust exposure may induce various lung diseases, including pneumoconiosis and chronic obstructive pulmonary disease (COPD). The features of combined COPD and pneumoconiosis have not been well described, and this may hamper the management. This study aimed to describe the prevalence and characteristics as well as the risk factors of the combined diseases.

DESIGN

A cross-sectional study.

SETTING AND PARTICIPANTS

758 patients with pneumoconiosis were recruited at a single-medical centre. Of these, 675 patients with pneumoconiosis, including asbestosis, silicosis, coal workers' pneumoconiosis and other pneumoconiosis, was eligible for analysis.

PRIMARY OUTCOME MEASURES

COPD was diagnosed based on clinical features and/or history of exposure to risk factors and post bronchodilator forced expiratory volume in 1 s (FEV₁)/forced vital capacity (FVC) ratio <0.7. Clinical data were collected from predesigned medical reports. The patients underwent both chest radiograph and high-resolution CT scans. Risk factors for combined COPD and pneumoconiosis were analysed using regression analysis.

RESULTS

COPD prevalence overall was 32.7% (221/675) and was the highest in silicosis (84/221) and coal workers' pneumoconiosis (100/221). COPD prevalence increased with smoking pack-years, dust exposure duration and pneumoconiosis stage. Patients with combined diseases had lower body mass index, higher smoking index and worse pulmonary function. Risk factors for combined diseases included heavy smoking, silica or coal exposure and advanced pneumoconiosis. The interaction between dust exposure and smoking in COPD was also identified. The risk of combined COPD significantly increased with heavy smoking and silica or coal exposure (OR 5.49, 95% CI 3.04 to 9.93, p<0.001).

CONCLUSIONS

COPD is highly prevalent in patients with pneumoconiosis, especially patients with silicosis and coal workers' pneumoconiosis. Occupational dust exposure as well as heavy smoking is associated with an increased risk of combined COPD and pneumoconiosis, which demands an effective preventive intervention.

The Association of Airflow Obstruction with Occupational Exposures in a Sample of Rural Adults in Iowa

A recent article reported that occupational exposure to vapor-gas, dust, and fumes (VGDF) was more common in a sample of rural adults than in a sample of adults in urban settings. In another study of the same urban adults, airflow obstruction (AO) was associated with occupational VGDF and the combination of smoking and occupational exposure. The goal of the current study was to determine if similar associations were evident in the sample of rural adults. We analyzed enrollment data from the Keokuk County Rural Health Study (KCRHS), which investigated the health of rural residents in Iowa. We used the same methods as the study of urban adults. A job-exposure matrix (JEM) assigned an occupational VGDF exposure level based on each participants' last reported job. The health outcome was AO, defined as both the forced expiratory volume in one second (FEV1) and the FEV1/forced vital capacity (FVC) ratio < lower limit of normal. Of the 1699 KCRHS participants, 436 (25.7%) had high total VGDF occupational exposure, 661 (38.9%) had ever smoked cigarettes, and 110 (6.5%) had AO. The crude frequency of AO increased across the joint categories of smoking (never, ever) and high exposure (no, yes) (p < 0.05 for linear trend). After adjusting for potential confounders, AO was associated with high total occupational VGDF exposure only among smokers (OR = 1.81, 95% CI 1.002 to 3.26). In conclusion, the association of AO with occupational exposure in the current study of rural adults was similar to what was previously observed among urban adults.

Rural Residence and Poverty Are Independent Risk Factors for Chronic Obstructive Pulmonary Disease in the United States

RATIONALE

In developing countries, poor and rural areas have a high burden of chronic obstructive pulmonary disease (COPD), and environmental pollutants and indoor burning of biomass have been implicated as potential causal exposures. Less is known about the prevalence of COPD in the United States with respect to urban-rural distribution, poverty, and factors that uniquely contribute to COPD among never-smokers.

OBJECTIVES

To understand the impact of urban-rural status, poverty, and other community factors on COPD prevalence nationwide and among never-smokers.

METHODS

We studied a nationally representative sample of adults in the National Health Interview Survey 2012-2015, with data linkage between neighborhood data from the U.S. Census's American Community Survey and the National Center for Health Statistics Urban-Rural Classification Scheme. The main outcome was COPD prevalence.

MEASUREMENTS AND MAIN RESULTS

The prevalence of COPD in poor, rural areas was almost twice that in the overall population (15.4% vs. 8.4%). In adjusted models, rural residence (odds ratio [OR], 1.23; P < 0.001) and census-level poverty (OR, 1.12; P = 0.012) were both associated with COPD prevalence, as were indicators of household wealth. Among never-smokers, rural residence was also associated with COPD (OR, 1.34; P < 0.001), as was neighborhood use of coal for heating (OR, 1.09; P < 0.001).

CONCLUSIONS

In a nationally representative sample, rural residence and poverty were risk factors for COPD, even among never-smokers. The use of coal for heating was also a risk factor for COPD among never-smokers. Future disparities research to elucidate contributors to COPD development in poor and rural areas, including assessments of heating sources and environmental pollutants, is needed.

Occupational exposure and airflow obstruction and self-reported COPD among ever-employed US adults using a COPD-job exposure matrix

INTRODUCTION

This study examined the association of spirometry-defined airflow obstruction and self-reported COPD defined as self-reported doctor diagnosed chronic bronchitis or emphysema, with occupational exposure among ever-employed US adults.

METHODS

Data were obtained from the National Health and Nutrition Examination Survey (NHANES) 2007-2008 to 2011-2012, a nationally representative study of the non-institutionalized civilian US population. Reported current and/or longest held job were used to create prevalence estimates and prevalence odds ratios (PORs) (adjusted for age, gender, race, and smoking status) for airflow obstruction and self-reported COPD by occupational exposure, determined using both NHANES participants' self-reported exposures and eight categories of COPD job exposure matrix (JEM) assigned exposures.

RESULTS

Significant PORs for airflow obstruction and self-reported COPD respectively were observed with self-reported exposure for ≥20 years to mineral dust (POR = 1.44; 95% confidence interval (CI) 1.13-1.85; POR = 1.69; 95% CI 1.17-2.43) and exhaust fumes (POR = 1.65; 95% CI 1.27-2.15; POR = 2.22; 95% CI 1.37-3.58). Airflow obstruction or self-reported COPD were also associated with COPD-JEM assigned high exposure to mineral dust, combined dust, diesel exhaust, vapor-gas, sensitizers, and overall exposure.

CONCLUSION

Airflow obstruction and self-reported COPD are associated with both self-reported and JEM-assigned exposures.

Socioeconomic variables explain rural disparities in US mortality rates: Implications for rural health research and policy

Objectives

Rural disparities in age-adjusted mortality are growing in the United States. While socioeconomic variables have been found to explain significant variation in life expectancy across US counties, previous research has not examined the role of socioeconomic variables in explaining rural mortality disparities. The purpose of this study was to quantify the rural mortality disparity after controlling for socioeconomic variables.

Methods

Recursive partitioning, or tree regression, was used to fit models predicting premature mortality across counties in the United States, adjusted for age, median income, and percent in poverty in 4 time periods (from 2004 to 2012) with and without inclusion of an urban-rural variable.

Results

We found median income and percent in poverty explained about 50% of the variation in age-adjusted premature mortality rates across US counties in each of the four time periods. After controlling for these socioeconomic variables, rural mortality disparities largely disappeared, explaining less than 2% of the variance in premature mortality.

Conclusions

Addressing poverty and other socioeconomic issues should be a priority to improve health in rural communities. Interventions designed to target social determinants of health in rural areas are needed to address the growing rural mortality disparity that is largely explained by measures of poverty and income. Researchers examining rural health disparities should routinely include socioeconomic variables in their analyses.