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

Narrative review of occupational exposures and noncommunicable diseases

OBJECTIVE

Within the scope of the Exposome Project for Health and Occupational Research on applying the exposome concept to working life health, we aimed to provide a broad overview of the status of knowledge on occupational exposures and associated health effects across multiple noncommunicable diseases (NCDs) to help inform research priorities.

METHODS

We conducted a narrative review of occupational risk factors that can be considered to have "consistent evidence for an association," or where there is "limited/inadequate evidence for an association" for 6 NCD groups: nonmalignant respiratory diseases; neurodegenerative diseases; cardiovascular/metabolic diseases; mental disorders; musculoskeletal diseases; and cancer. The assessment was done in expert sessions, primarily based on systematic reviews, supplemented with narrative reviews, reports, and original studies. Subsequently, knowledge gaps were identified, e.g. based on missing information on exposure-response relationships, gender differences, critical time-windows, interactions, and inadequate study quality.

RESULTS

We identified over 200 occupational exposures with consistent or limited/inadequate evidence for associations with one or more of 60+ NCDs. Various exposures were identified as possible risk factors for multiple outcomes. Examples are diesel engine exhaust and cadmium, with consistent evidence for lung cancer, but limited/inadequate evidence for other cancer sites, respiratory, neurodegenerative, and cardiovascular diseases. Other examples are physically heavy work, shift work, and decision latitude/job control. For associations with limited/inadequate evidence, new studies are needed to confirm the association. For risk factors with consistent evidence, improvements in study design, exposure assessment, and case definition could lead to a better understanding of the association and help inform health-based threshold levels.

CONCLUSIONS

By providing an overview of knowledge gaps in the associations between occupational exposures and their health effects, our narrative review will help setting priorities in occupational health research. Future epidemiological studies should prioritize to include large sample sizes, assess exposures prior to disease onset, and quantify exposures. Potential sources of biases and confounding need to be identified and accounted for in both original studies and systematic reviews.

Issue 3-The occupational burden of respiratory diseases, an update

INTRODUCTION AND AIMS

Workplace exposures are widely known to cause specific occupational diseases such as silicosis and asbestosis, but they also can contribute substantially to causation of common respiratory diseases. In 2019, the American Thoracic Society (ATS) and the European Respiratory Society (ERS) published a joint statement on the occupational burden of respiratory diseases. Our aim on this narrative review is to summarise the most recent evidence published after the ATS/ERS statement as well as to provide information on traditional occupational lung diseases that can be useful for clinicians and researchers.

RESULTS

Newer publications confirm the findings of the ATS/ERS statement on the role of workplace exposure in contributing to the aetiology of the respiratory diseases considered in this review (asthma, COPD, chronic bronchitis, idiopathic pulmonary fibrosis, hypersensitivity pneumonitis, infectious pneumonia). Except for COPD, chronic bronchitis and infectious pneumonia, the number of publications in the last 5 years for the other diseases is limited. For traditional occupational lung diseases such as silicosis and asbestosis, there are old as well as novel sources of exposure and their burden continues to be relevant, especially in developing countries.

CONCLUSIONS

Occupational exposure remains an important risk factor for airways and interstitial lung diseases, causing occupational lung diseases and contributing substantially in the aetiology of common respiratory diseases. This information is critical for public health professionals formulating effective preventive strategies but also for clinicians in patient care. Effective action requires shared knowledge among clinicians, researchers, public health professionals, and policy makers.

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.

Awareness of COPD and Its Risk Factors Among the Adult Population of the Aseer Region, Saudi Arabia

Introduction

Epidemiological studies are urgently needed to assess the prevalence of COPD in the region to determine the baseline, against which the future trends in the risk factor levels can be assessed and preventive strategies be planned to promote health among the population. Therefore, this study was undertaken to assess the awareness of COPD and its risk factors in Saudi Arabia.

Materials and Methods

The cross-sectional study was conducted among the general adult population aged 18 years and above living in the Aseer region. A minimum sample of 385 was targeted, using the Raosoft sample size calculator. An online questionnaire was prepared in both English and Arabic language using Google forms and distributed among participants through social media.

Results

It was observed that less than one-third (116, 30.12%) of the study population had ever heard about COPD. Nearly one-third spent time with smokers. Among all, 223 (57.3%) respondents had never heard and 46 (11.9%) respondents did not know anything about COPD. The majority correctly knew that the lungs are the primary organ affected by COPD (92, 79.3%). Age, sex, marital status, income, and occupation showed a significant association with COPD awareness. Nearly 41.4% knew that COPD progresses exclusively with age, COPD is more expensive for society than lung cancer (49.0%), cigarette smoking affects COPD (34.5%), COPD is fully recoverable with short-term antibiotics (35.0%), COPD lasts more than 18 months (48.1%), COPD can worsen with smoke exposure (37.4%), lead to disability (46.7%) and quitting smoking has an important role in preventing COPD (34.0%).

Conclusion

The awareness regarding the disease was low among the respondents. Only one-third correctly knew that quitting smoking has an important role in preventing COPD. This study projects an urgent need of improving awareness of COPD and its risk factors in the general population.

Occupational COPD-The most under-recognized occupational lung disease?

Chronic obstructive pulmonary disease (COPD) is caused by exposure to noxious particles and gases. Smoking is the main risk factor, but other factors are also associated with COPD. Occupational exposure to vapours, gases, dusts and fumes contributes to the development and progression of COPD, accounting for a population attributable fraction of 14%. Workplace pollutants, in particular inorganic dust, can initiate airway damage and inflammation, which are the hallmarks of COPD pathogenesis. Occupational COPD is still underdiagnosed, mainly due to the challenges of assessing the occupational component of the disease in clinical settings, especially if other risk factors are present. There is a need for specific education and training for clinicians, and research with a focus on evaluating the role of occupational exposure in causing COPD. Early diagnosis and identification of occupational causes is very important to prevent further decline in lung function and to reduce the health and socio-economic burden of COPD. Establishing details of the occupational history by general practitioners or respiratory physicians could help to define the occupational burden of COPD for individual patients, providing the first useful interventions (smoking cessation, best therapeutic management, etc.). Once patients are diagnosed with occupational COPD, there is a wide international variation in access to specialist occupational medicine and public health services, along with limitations in workplace and income support. Therefore, a strong collaboration between primary care physicians, respiratory physicians and occupational medicine specialists is desirable to help manage COPD patients' health and social issues.

Associations Between Physical Activity, Smoking Status, and Airflow Obstruction and Self-Reported COPD: A Population-Based Study

Background

Chronic obstructive pulmonary disease (COPD) is a preventable and treatable disease with an increased mortality rate in recent years, mainly caused by exposure to tobacco smoke. Regular physical activity is thought to diminish the risk of COPD exacerbation, while very few studies investigate the interaction between smoking and physical activity on COPD development. This study aims to investigate the association between smoking status, physical activity and prevalent COPD.

Methods

This study analyzed data of adults 20 to 79 years old from the National Health and Nutrition Examination Survey (NHANES) 2007–2012.

Results

A total of 6404 participants aged 20–79 were included and divided into four groups by their physical activity levels and smoking status. Amongst, 2819 (43.7%) were physically active non-smokers, 957 (14.8%) were physically inactive non-smokers, 1952 (30.3%) were physically active smokers, and 717 (11.1%) were physically inactive smokers. Prevalence of airflow obstruction were 5.7%, 7.1%, 17.7% and 18.6%, respectively. After adjustment, physically active smokers (aOR=2.71, 95% CI=1.94–3.80) and physically inactive smokers (aOR=2.70, 95% CI=1.78–4.09) but not physically active non-smokers were more likely to have airflow obstruction than physically active non-smokers. These associations were similar among most subgroups by age, sex, or BMI. Among smokers, being physically inactive was not significantly associated with a greater chance for prevalent airflow obstruction than being physically active.

Conclusion

Smokers, regardless of their physical activity level, are more likely to have airflow obstruction as compared with physically active non-smokers. Within smokers, being physically inactive poses no excess chance to be airflow obstructed. The findings indicate that physical activity level seem not altering the relationship between smoking and airflow obstruction.

Prevalence and severity of abnormal lung function among US former coal miners with and without radiographic coal workers' pneumoconiosis

OBJECTIVES

Examination of lung function abnormalities among coal miners has historically focused on actively working miners. This likely underestimates the true burden of chronic respiratory disease. The objective of this study was to characterise patterns and severity of lung function impairment among a population of former coal miners.

METHODS

Cross-sectional data from 2568 former coal miners evaluated at eight US Black Lung clinics in a 12-month period were retrospectively analysed for patterns of prebronchodilator spirometric abnormality and severity of lung function impairment. Spirometry data from a subset of former miners with chest radiographs were analysed based on the presence and severity of coal workers' pneumoconiosis (CWP).

RESULTS

Abnormal spirometry was identified in 56.6% of subjects. The age-standardised prevalence of airflow obstruction among miners aged ≥45 years was 18.9% overall and 12.2% among never smokers. Among 1624 subjects who underwent chest radiography, the prevalence and severity of abnormal spirometry increased with worsening radiographic category for pneumoconiosis. Of never-smoking former miners without radiographic CWP, 39.0% had abnormal spirometry; 25.1% had abnormally low forced expiratory volume in 1 s (FEV₁), and 17.1% had moderate to severe FEV₁ impairment.

CONCLUSIONS

Abnormal spirometry is common among former coal miners. While ever-smoking former miners had higher rates of airflow obstruction, never-smoking former miners also demonstrated clinically significant airflow obstruction, including those without radiographic pneumoconiosis. These findings demonstrate the importance of recognising physiological as well as imaging manifestations of coal mine dust lung diseases in former miners.

Association between chronic obstructive pulmonary disease (COPD) and occupational exposures: A hospital based quantitative cross-sectional study among the Bangladeshi population

The association between chronic obstructive pulmonary disease (COPD) and occupational exposures are less studied in Bangladeshi context, despite the fact that occupational exposures are serious public health concerns in Bangladesh. Therefore, this study aimed to evaluate this association considering demographic, health and smoking characteristics of Bangladeshi population. This was a hospital-based quantitative study including 373 participants who were assessed for COPD through spirometry testing. Assessment of occupational exposures was based on both self-reporting by respondents and ALOHA based job exposure matrix (JEM). Here, among the self-reported exposed group (n = 189), 104 participants (55%) were found with COPD compared to 23 participants (12.5%) in unexposed group (n = 184) that differed significantly (p = 0.00). Similarly, among the JEM measured low (n = 103) and high exposed group (n = 236), 23.3% and 41.5% of the participants were found with COPD respectively; compared to unexposed group (14.7%; n = 34), that differed significantly also (p = 0.00). Likewise, participants with longer self-reported occupational exposures (>8 years) showed significantly (p = 0.00) higher proportions of COPD (79.5%) compared to 40.4% in shorter exposure group (1-8 years). Similarly, significant (p = 0.00) higher cases of COPD were observed among the longer cumulative exposure years (>9 years) group than the shorter cumulative exposure years (1-9 years) group in JEM. While combining smoking and occupational exposure, the chance of developing COPD among the current, former and non-smokers of exposed group were 7.4, 7.2 and 12.7 times higher respectively than unexposed group. Furthermore, logistic analysis revealed that after adjustments for confounding risk factors, the chance of developing COPD among the self-reported exposure group was 6.3 times higher (ORs: 6.3, p = 0.00) than unexposed group; and JEM exposure group has odds of 2.8 and 1.1 respectively (p<0.05) for high and low exposures. Further studies are needed to reinforce this association between COPD and occupational exposure in Bangladesh.

Prevalence of spirometry-defined airflow obstruction in never-smoking working US coal miners by pneumoconiosis status

INTRODUCTION

This study estimated the prevalence of spirometry-defined airflow obstruction and coal workers' pneumoconiosis (CWP) among never-smoking coal miners participating in the National Institute for Occupational Safety and Health (NIOSH) Coal Workers' Health Surveillance Program (CWHSP).

METHODS

Data were from working miners screened by a CWHSP mobile unit who had valid spirometry and chest radiography results. Spirometry-defined airflow obstruction was determined when the ratio of forced expiratory volume in the first second to forced vital capacity is less than the lower limit of normal. Chest radiographs were classified according to the International Labour Office system to identify pneumoconiosis, including the most severe form of pneumoconiosis, progressive massive fibrosis (PMF).

RESULTS

Prevalence of airflow obstruction among never-smoking coal miners in this sample was 7.7% overall, 16.4% among miners with CWP and 32.3% among miners with PMF. Airflow obstruction was significantly associated with CWP and PMF.

CONCLUSIONS

There was a higher prevalence of airflow obstruction among never-smoking coal miners with pneumoconiosis compared with those without pneumoconiosis. These findings support prior research on airflow obstruction and smoking and show pneumoconiosis might present with an obstructive pattern regardless of smoking status.