Occupational contribution to the burden of chronic obstructive pulmonary disease

Asthma, chronic obstructive pulmonary disease, and asthma-COPD overlap among US working adults

BACKGROUND

Asthma-COPD overlap (ACO) is a respiratory condition with more severe respiratory symptoms, poorer quality of life, and increased hospital admissions compared with asthma or COPD alone.

OBJECTIVES

Estimate asthma, chronic obstructive pulmonary disease (COPD), and ACO prevalence among workers by industry and occupation and assess physical and mental health status, healthcare utilization, among workers with ACO.

METHODS

The 2014-2018 National Health Interview Survey (NHIS) data for working adults aged ≥18 years employed (sample n = 99,424) in the 12 months prior to the survey were analyzed. Age-adjusted ACO, COPD and asthma prevalence and prevalence ratios adjusted for age, sex, race and smoking status were estimated.

RESULTS

During 2014-2018, of the estimated 166 million (annual average) US workers, age-adjusted asthma, COPD, and ACO prevalence was 6.9%, 4.0%, and 1.1%, respectively. ACO prevalence was highest among workers aged ≥65 years (2.0%), females (1.6%), current smokers (1.9%), those living below the federal poverty level (2.3%), and workers in the accommodation and food services (1.6%) industry and personal care and service (2.3%) occupations. Workers with ACO had more frequent (p < 0.05) physician office visits, emergency department visits; and were more likely to be in poorer mental health, obese, have more lost workdays, more bed days, and comorbidities compared to workers with asthma alone and workers with COPD alone.Conclusion: Higher ACO prevalence among worker groups and increased healthcare utilization underscores the need for early identification of asthma and COPD, assessment of potential workplace exposures, and implementation of tailored interventions to reduce ACO among working adults.

Impact of Previous Occupational Exposure on Outcomes of Chronic Obstructive Pulmonary Disease

Occupational exposures have been regarded as a risk factor for the development of chronic obstructive pulmonary disease (COPD). However, there is little knowledge regarding the effect of occupational exposure on the treatment outcomes of COPD. Therefore, the aim of this study was to evaluate the question of whether occupational exposure can have a potential impact on COPD outcomes. Methods: Information regarding self-reported occupational exposure for 312 patients with COPD from the Korean Obstructive Lung Disease (KOLD) Cohort were included. A comparison of the rate of acute exacerbation, annual lung function change, and quality of life according to the presence or absence of occupational exposure was performed. Results: Seventy-six patients (24.4%) had experienced occupational exposure; chemical materials were most common. At enrollment, a higher COPD-specific version of the St. George Respiratory Questionnaire total score (39.7 ± 18.8 vs. 33.1 ± 17.6, p = 0.005) and a higher exacerbation history in the past year (30.3% vs. 17.5%, p = 0.017) were observed for patients with occupational exposure compared to those without occupational exposure. Furthermore, in the follow-up period, after adjusting for potential confounders, a higher frequency of acute exacerbation (odd ratio, 1.418; 95% confidence interval, 1.027–1.956; p = 0.033) and a more rapid decline in forced expiratory volume in 1 s (p = 0.009) was observed for COPD patients with occupational exposure compared to those without occupational exposure. Conclusions: In the KOLD cohort, worse outcomes in terms of exacerbation rate and change in lung function were observed for COPD patients with occupational exposure compared to those without occupational exposure. These findings suggest that occupational exposure not only is a risk factor for COPD but also might have a prognostic impact on COPD.

COPD risk among older construction workers-Updated analyses 2020

BACKGROUND

A 2010 study of construction workers participating in medical screening programs at the Department of Energy (DOE) nuclear facilities demonstrated increased chronic obstructive pulmonary disease (COPD) risk. The current study of a larger worker cohort allowed for a more nuanced analysis of COPD risk, including for employment beginning after the mid-1990s.

METHODS

Study participants included 17,941 workers with demographic and smoking data and spirometry with a minimum of three recorded expiratory efforts and reproducibility of forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV₁ ) of 0.2 L or less. COPD was defined as a FEV₁ /FVC ratio below the lower limit of normal using established prediction equations without use of bronchodilation. Stratified analyses explored COPD prevalence by demographic variables and trade. Logistic regression analyses assessed risks by trade and time periods of trade and DOE site work, controlling for age, gender, race/ethnicity, body mass index, and smoking.

RESULTS

Overall COPD prevalence was 13.4% and 67.4% of cases were classified as moderate to severe. Compared to nonconstruction workers, construction trade workers were at significantly increased risk of all COPD (OR = 1.34, 95% CI = 1.29-1.79) and even more so for severe COPD (OR = 1.61, 95% CI = 1.32-1.96). The highest risk trades were cement masons/bricklayers (OR = 2.36; 95% CI = 1.71-3.26) and roofers (OR = 2.22; 95% CI = 1.48-3.32). Risk among workers employed after 1995 was elevated but not statistically significant.

CONCLUSIONS

Construction workers are at increased COPD risk. Results support the prevention of both smoking and occupational exposures to reduce these risks. While the number of participants employed after 1995 was small, patterns of risk were consistent with findings in the overall cohort.

Insights from Twitter About Public Perceptions of Asthma, COPD, and Exposures

OBJECTIVE

The aim of this study was to analyze tweets concerning asthma and chronic obstructive pulmonary disease (COPD).

METHODS

Approximately 40,000 tweets containing asthma or COPD were analyzed. Lexical analysis ranked terms and domains of interest, compared COPD with asthma tweets, evaluated co-occurrence of terms within tweets, and assessed differences by source (personal, institutional, or retweet). The frequency of indicator terms relevant to occupational health was determined.

RESULTS

Many tweets address community pollution and effects on children, but there is much less interest in work-related factors and occupational regulatory agencies. Environment is considered much more relevant for asthma than COPD.

CONCLUSION

Although epidemiologic studies demonstrate a major burden of occupational factors upon both diseases, significantly improved outreach is needed to overcome inadequate public interest. Social media represent a valuable resource for assessing perceptions about work-related disease and potentially discovering new associations.

Estimation of an Exposure Threshold Value for Compensation of Silica-Induced COPD Based on Longitudinal Changes in Pulmonary Function

(1) Background: To estimate the cumulative exposure to respirable crystalline silica (RCS) that reduces lung function to an extent corresponding with airway obstruction equivalent to chronic obstructive pulmonary disease (COPD). (2) Methods: The study is based on a miners' cohort with longitudinal data on lung function and RCS exposure. Random-effects linear regression models, allowing for a possible threshold concerning the exposure concentration were used to analyze the impact of RCS on the ratio of forced expiratory volume in 1 s and forced vital capacity (FEV₁/FVC). The proposed threshold is the amount of RCS resulting in a decrease in FEV₁/FVC from the expected value to the lower limit of normal. (3) Results: The analysis shows that a threshold model fits the data significantly better than the usual linear model. The estimated threshold value for the exposure concentration is 0.089 mg/m³. Using this threshold, the estimate for the corresponding reference dose for RCS is 2.33 mg/m³·y. (4) Conclusions: The analysis confirmed that RCS has a negative impact on lung function. The effect is primarily due to exposure above a concentration threshold of 0.1 mg/m³. It is recommended that COPD should be compensated as an occupational disease if cumulative exposure was at least 2 mg/m³·y above this threshold.

Occupational exposure to inhaled pollutants and risk of airflow obstruction: a large UK population-based UK Biobank cohort

Background

Although around 10% to 15% of COPD burden can be attributed to workplace exposures, little is known about the role of different airborne occupational pollutants (AOP). The main aim of the study was to assess the effect size of the relationship between various AOP, their level and duration of exposure with airflow obstruction (AFO).

Methods

A cross-sectional analysis was conducted in 228 614 participants from the UK Biobank study who were assigned occupational exposure using a job exposure matrix blinded to health outcome. Adjusted prevalence ratios (PRs) and 95% CI for the risk of AFO for ever and years of exposure to AOPs were estimated using robust Poisson model. Sensitivity analyses were conducted for never-smokers, non-asthmatic and bi-pollutant model.

Results

Of 228 614 participants, 77 027 (33.7%) were exposed to at least one AOP form. 35.5% of the AFO cases were exposed to vapours, gases, dusts or fumes (VGDF) and 28.3% to dusts. High exposure to vapours increased the risk of occupational AFO by 26%. Exposure to dusts (adjusted PR=1.05; 95% CI 1.01 to 1.08), biological dusts (1.05; 1.01 to 1.10) and VGDF (1.04; 1.01 to 1.07) showed a significantly increased risk of AFO, however, statistically not significant following multiple testing. There was no significant increase in risk of AFO by duration (years) of exposure in current job. The results were null when restricted to never-smokers and when a bi-pollutant model was used. However, when data was analysed based on the level of exposure (low, medium and high) compared with no exposure, directionally there was increase in risk for those with high exposure to vapours, gases, fumes, mists and VGDF but statistically significant only for vapours.

Conclusion

High exposure (in current job) to airborne occupational pollutants was suggestive of higher risk of AFO. Future studies should investigate the relationship between lifetime occupational exposures and COPD.

Prevalence of COPD among workers with work-related asthma

Objective: Concurrent asthma and chronic obstructive pulmonary disease (COPD) diagnoses occur in 15%-20% of patients, and have been associated with worse health outcomes than asthma or COPD alone. Work-related asthma (WRA), asthma that is caused or made worse by exposures in the workplace, is characterized by poorly controlled asthma. The objective of this study was to assess the proportion of ever-employed adults (≥18 years) with current asthma who have been diagnosed with COPD, by WRA status.Methods: Data from 23 137 respondents to the 2012-2014 Behavioral Risk Factor Surveillance System Asthma Call-back Survey from 31 states and the District of Columbia were examined. Logistic regression was used to calculate adjusted prevalence ratios (PRs), examining six disjoint categories of WRA-COPD overlap with non-WRA/no COPD as the referent category.Results: An estimated 51.9% of adults with WRA and 25.6% of adults with non-WRA had ever been diagnosed with COPD. Adults with WRA/COPD were more likely than those with non-WRA/no COPD to have an asthma attack (PR = 1.77), urgent treatment for worsening asthma (PR = 2.85), an asthma-related emergency room visit (PR = 4.21), overnight stay in a hospital because of asthma (PR = 6.57), an activity limitation on 1-13 days (PR = 2.01) or ≥14 days (PR = 5.02), and very poorly controlled asthma (PR = 3.22).Conclusions: COPD was more frequently diagnosed among adults with WRA than those with non-WRA, and adults diagnosed with both WRA and COPD appear to have more severe adverse asthma outcomes than those with non-WRA and no COPD.

Self-reported intake of fruit and vegetables and risk of chronic obstructive pulmonary disease: A nation-wide twin study

BACKGROUND

Although smoking is the major risk factor for chronic obstructive pulmonary disease (COPD) many patients with obstructive lung function suggesting COPD are never-smokers. Therefore, other lifestyle factors have been suggested as risk factors.

AIMS

i) To examine the association between self-reported intake of fruit and vegetables and risk of COPD and ii) to examine whether the association between these traits are due to underlying genetic factors.

METHODS

12,449 twins, aged 40-80, from the Danish Twin Registry were recruited. The participants completed a questionnaire on medical history and lifestyle factors and participated in clinical examination. COPD was defined according to ATS/ERS recommendations. Multivariate logistic regressions were used to estimate the risk of COPD in individuals with a low intake of fruit and vegetables. Co-twin control analyses were performed to examine whether the association between fruit and vegetables and COPD is explained by genetic factors. Self-reported physician-diagnosed asthmatic individuals were excluded.

RESULTS

Of the 11,458 individuals were included in the analyses, 48% of the participants were males. Mean age was 58.9 (years)±SD 9.6, mean BMI (kg/m²)26.6 ± SD 4.4. A multivariate logistic regression, including sex, age and BMI showed that both smoking, no and heavy drinking and physical inactivity were independent predictors of COPD. There was a significant frequency-pendent association between intake of fruit and vegetables and increased risk of COPD. Conditional logistic regression analyses showed that the association might be controlled by genetic factors.

CONCLUSIONS

This study shows that low intake of fruit and vegetables is associated with an increased risk of COPD and the association might be under influence of genetic factors.

Defining and targeting health disparities in chronic obstructive pulmonary disease

The global burden of chronic obstructive pulmonary disease (COPD) continues to grow in part due to better outcomes in other major diseases and in part because a substantial portion of the worldwide population continues to be exposed to inhalant toxins. However, a disproportionate burden of COPD occurs in people of low socioeconomic status (SES) due to differences in health behaviors, sociopolitical factors, and social and structural environmental exposures. Tobacco use, occupations with exposure to inhalant toxins, and indoor biomass fuel (BF) exposure are more common in low SES populations. Not only does SES affect the risk of developing COPD and etiologies, it is also associated with worsened COPD health outcomes. Effective interventions in these people are needed to decrease these disparities. Efforts that may help lessen these health inequities in low SES include 1) better surveillance targeting diagnosed and undiagnosed COPD in disadvantaged people, 2) educating the public and those involved in health care provision about the disease, 3) improving access to cost-effective and affordable health care, and 4) markedly increasing the efforts to prevent disease through smoking cessation, minimizing use and exposure to BF, and decreasing occupational exposures. COPD is considered to be one the most preventable major causes of death from a chronic disease in the world; therefore, effective interventions could have a major impact on reducing the global burden of the disease, especially in socioeconomically disadvantaged populations.

Chronic bronchitis incidence in the extended cohort of Mayak workers first employed during 1948-1982

OBJECTIVES

This paper describes findings from the study of chronic bronchitis (CB) incidence after occupational exposure to ionising radiation among workers employed at Russian Mayak Production Association (PA) during 1948 and 1982 and followed up until 2008 based on 'Mayak Worker Dosimetry System 2008'.

METHODS

Analyses were based on 2135 verified cases among 21 417 workers. Rate ratios (RR) were estimated by categorical analysis for non-radiation and radiation factors. Excess rate ratios per Gy (ERR/Gy) of external or internal exposures with adjustments via stratification on other factors were calculated.

RESULTS

The interesting finding in relation to non-radiation factors was a sharp increase in the RR for CB incidence before 1960, which could be caused by a number of factors. Analyses restricted to the follow-up after 1960 revealed statistically significant associations of the CB incidence and external γ-ray radiation, ERR/Gy=0.14 (95% CI 0.02 to 0.28) having adjusted for sex, attained age, calendar period, plant, smoking status and lung α-particle dose, and internal α-particle radiation, ERR/Gy=1.14 (95% CI 0.41 to 2.18) having adjusted for sex, attained age, calendar period, plant, smoking status and lung γ-ray dose and ERR/Gy=1.19 (95% CI 0.32 to 2.53) having additionally adjusted for pre-employment occupational hazards and smoking index instead of smoking status.

CONCLUSIONS

Analyses of CB incidence in the study cohort identified positive significant association with occupational exposure to radiation: however, there are no similar studies of CB incidence in relation to radiation in other cohorts to date with which a meaningful comparison of the results could be made.

Household Air Pollution Exposure and Influence of Lifestyle on Respiratory Health and Lung Function in Belizean Adults and Children: A Field Study

Household air pollution (HAP) contributes to the global burden of disease. Our primary purpose was to determine whether HAP exposure was associated with reduced lung function and respiratory and non-respiratory symptoms in Belizean adults and children. Our secondary purpose was to investigate whether lifestyle (physical activity (PA) and fruit and vegetable consumption (FV)) is associated with reported symptoms. Belizean adults (n = 67, 19 Male) and children (n = 23, 6 Male) from San Ignacio Belize and surrounding areas participated in this cross-sectional study. Data collection took place at free walk-in clinics. Investigators performed initial screenings and administered questionnaires on (1) sources of HAP exposure; (2) reported respiratory and non-respiratory symptoms and (3) validated lifestyle questionnaires. Participants then performed pulmonary function tests (PFTs) and exhaled breath carbon monoxide (CO). There were no significant associations between HAP exposure and pulmonary function in adults. Increased exhaled CO was associated with a significantly lower forced expiratory volume in 1-s divided by forced vital capacity (FEV₁/FVC) in children. Exposed adults experienced headaches, burning eyes, wheezing and phlegm production more frequently than unexposed adults. Adults who met PA guidelines were less likely to experience tightness and pressure in the chest compared to those not meeting guidelines. In conclusion, adults exposed to HAP experienced greater respiratory and non-respiratory symptoms, which may be attenuated by lifestyle modifications.

A case-control study of airways obstruction among construction workers

BACKGROUND

While smoking is the major cause of chronic obstructive pulmonary disease (COPD), occupational exposures to vapors, gases, dusts, and fumes (VGDF) increase COPD risk. This case-control study estimated the risk of COPD attributable to occupational exposures among construction workers.

METHODS

The study population included 834 cases and 1243 controls participating in a national medical screening program for older construction workers between 1997 and 2013. Qualitative exposure indices were developed based on lifetime work and exposure histories.

RESULTS

Approximately 18% (95% CI = 2-24%) of COPD risk can be attributed to construction-related exposures, which are additive to the risk contributed by smoking. A measure of all VGDF exposures combined was a strong predictor of COPD risk.

CONCLUSIONS

Construction workers are at increased risk of COPD as a result of broad and complex effects of many exposures acting independently or interactively. Control methods should be implemented to prevent worker exposures, and smoking cessation should be promoted.

The association between blood cadmium level and airflow obstruction in Korean men

BACKGROUND

Most humans are exposed to environmental contaminants via inhalation. Various toxic inhalants cause lung damage with pathologic changes to the airway system. Lung function decline is an important cause of morbidity and mortality worldwide.

AIM

To consider the potential burden of cadmium on pulmonary disease, this study examined the relationship between blood cadmium levels and airflow obstruction in a Korean general population.

SUBJECTS AND METHODS

Data from the Korean National Health and Nutrition Examination Surveys from 2008-2011 were used. Male participants were selected who were older than 40 years, who had completed a reliable pulmonary function test and for who measurements of blood cadmium levels were available (n = 1974). The pulmonary function tests were undertaken and airflow obstruction was defined when forced vital capacity/forced expiratory volume in 1 second ratio < 0.7.

RESULTS

In an age-adjusted logistic regression model, blood cadmium levels correlated with the risk of obstructive airflow pattern in total participants as well as in smokers or never smokers. Further adjustment for BMI, current occupation and educational level did not attenuate these associations among total participants, smokers and never smokers (OR = 2.53, 95% CI = 1.83-3.50 in total; OR = 2.17, 95% CI = 1.55-3.02 in smokers; OR = 3.71, 95% CI = 1.48-9.33 in never smokers).

CONCLUSIONS

In conclusion, blood cadmium level was associated with airflow obstruction independently of smoking history and that association was still significant in never smokers. Careful attention is needed for the general population who are potentially exposed to cadmium.

Risks of a lifetime in construction. Part II: Chronic occupational diseases

BACKGROUND

We developed working-life estimates of risk for dust-related occupational lung disease, COPD, and hearing loss based on the experience of the Building Trades National Medical Screening Program in order to (1) demonstrate the value of estimates of lifetime risk, and (2) make lifetime risk estimates for common conditions among construction workers.

METHODS

Estimates of lifetime risk were performed based on 12,742 radiographic evaluations, 12,679 spirometry tests, and 11,793 audiograms.

RESULTS

Over a 45-year working life, 16% of construction workers developed COPD, 11% developed parenchymal radiological abnormality, and 73.8% developed hearing loss. The risk for occupationally related disease over a lifetime in a construction trade was 2-6 times greater than the risk in non-construction workers.

CONCLUSIONS

When compared with estimates from annualized cross-sectional data, lifetime risk estimates are highly useful for risk expression, and should help to inform stakeholders in the construction industry as well as policy-makers about magnitudes of risk.

Welding fume exposure and chronic obstructive pulmonary disease in welders

BACKGROUND

Occupational exposure is estimated to contribute 15% to the burden of chronic obstructive pulmonary disease (COPD). Welding fumes are suspected to accelerate the decline of lung function and development of COPD.

AIMS

To examine the relationship between welding fume exposure and COPD in Korean shipyard welders.

METHODS

The study involved a group of male welders working at two shipyards who underwent an annual health examination in 2010. Subjects completed a questionnaire about smoking habits and occupational history and a pulmonary function test (PFT) was carried out with strict quality control measures. Welding fume exposure concentrations were estimated using 884 measurements taken between 2002 and 2009 in one of the shipyards. Multiple linear and logistic regression was employed to evaluate the association between cumulative fume exposure and lung function parameters, controlling for age, height and cigarette smoking.

RESULTS

Two hundred and forty subjects participated, with a mean age of 48 and mean work duration of 15 years. The mean cumulative fume exposure was 7.7mg/m(3). The prevalence of COPD was 15%. FEV1 and FVC showed non-significant negative correlations with cumulative fume exposure. Odds ratios of COPD were significantly elevated for the middle (3.9; 95% CI 1.4-13.3) and high exposure groups (3.8; 95% CI 1.03-16.2) compared with the low fume exposure group.

CONCLUSIONS

Our findings support an association between welding fume exposure and increased risk of COPD. Further prospective study is needed to investigate whether this is a causal relationship.

Chronic obstructive pulmonary disease prevalence among nonsmokers by occupation in the United States

OBJECTIVE

To examine the prevalence of chronic obstructive pulmonary disease (COPD) among nonsmokers by occupation in the United States.

METHODS

The 1997 to 2004 National Health Interview Survey data for working adults aged 25 years or more were used to estimate the COPD prevalence and to examine change in COPD prevalence between 1997 to 2000 and 2001 to 2004 by occupational groups.

RESULTS

During 1997 to 2004, COPD prevalence was 2.8%. The COPD prevalence was highest in financial records processing (4.6%) occupations. There was a slight increase in COPD prevalence during the two survey periods from 2.8% during 1997 to 2000 compared with 2.9% during 2001 to 2004.

CONCLUSIONS

No significant changes in the COPD prevalence between the two periods were found. Nevertheless, the elevated COPD prevalence in certain occupational groups suggests that other risk factors play a role in developing COPD.

Biopersistent granular dust and chronic obstructive pulmonary disease: a systematic review and meta-analysis

Objective

Applying a systematic review to identify studies eligible for meta-analysis of the association between occupational exposure to inorganic dust and the development of chronic obstructive pulmonary disease (COPD), and conducting a meta-analysis.

Data Sources

Searches of PubMed and Embase for the time period 1970–2010 yielded 257 cross-sectional and longitudinal studies on people exposed to inorganic dust at the workplace with data on lung function. These studies were independently abstracted and evaluated by two authors; any disagreement was resolved by a third reviewer. Of 55 publications accepted for meta-analysis, 27 investigated the effects of occupational exposure to biopersistent granular dust (bg-dust).

Methods

A random effects meta-analysis allowed us to provide an estimate of the average exposure effect on spirometric parameters presented in forest plots. Between-study heterogeneity was assessed by using I² statistics, with I²>25% indicating significant heterogeneity. Publication bias was investigated by visual inspection of funnel plots. The influence of individual studies was assessed by dropping the respective study before pooling study-specific estimates.

Results

The mean FEV1 of workers exposed to bg-dust was 160 ml lower or 5.7% less than predicted compared to workers with no/low exposure. The risk of an obstructive airway disease—defined as FEV1/FVC < 70%—increased by 7% per 1 mg· m^-3 respirable bg-dust.

Conclusion

Occupational inhalative exposure to bg-dust was associated with a statistically significant decreased FEV1 and FEV1/FVC revealing airway obstruction consistent with COPD.

Obstructive pulmonary function impairment among Korean male workers exposed to organic solvents, iron oxide dust, and welding fumes

We evaluated spirometric obstructive pulmonary function impairment among workers who were occupationally exposed to organic solvents, iron oxide dust, or welding fumes. Data were collected from records of periodic health examinations of workers. In total, 448 Korean male workers were enrolled and classified into three exposure groups: exposure to organic solvents, iron oxide dust, or welding fumes. Logistic regression analysis was performed to evaluate the association between occupational exposure and pulmonary function. Compared to exposure to organic solvents, exposure to iron oxide dust was significantly associated with obstructive pulmonary function impairment (odds ratio [OR], 9.61; 95% confidence interval [CI], 2.20-41.97). The group exposed to welding fumes did not show a significantly higher OR compare to those exposed to organic solvents (OR, 2.83; 95% CI, 0.74-10.8). These results suggest that exposure to iron oxide dust has a greater association with obstructive pulmonary function impairment than exposure to organic solvents or welding fumes.

Occupational chronic obstructive pulmonary disease: an update

Chronic obstructive pulmonary disease represents a major cause of morbidity and mortality in industrialized and nonindustrialized countries. Although tobacco use remains the main factor associated with development of the disease, occupational risk factors represent an important and preventable cause. The most common occupationally related factors include exposure to organic dusts, metallic fumes, and a variety of other mineral gases and/or vapors. This article summarizes the literature on the subject and provides an update of the most recent advances in the field.

Occupational diesel exhaust exposure as a risk factor for chronic obstructive pulmonary disease

PURPOSE OF REVIEW

Chronic obstructive pulmonary disease (COPD) is a major source of morbidity and mortality worldwide. Although cigarette smoking is the major cause of COPD, occupational exposures have emerged as an important risk factor, especially in nonsmokers. In this review, we assess the state of the literature on the association of COPD with a specific occupational exposure, diesel exhaust.

RECENT FINDINGS

A large body of literature links general occupational exposures to dust and fumes with an increased risk of COPD, particularly in nonsmokers. Few studies, however, have explicitly examined the role of occupational diesel exhaust exposures to COPD risk. Suggestive recent findings link occupational diesel exposures to an increased risk of COPD.

SUMMARY

The available literature directly examining the effects of occupational diesel exhaust on risk of COPD is quite small, but does suggest that increasing exposures are associated with increasing risk. Additional research, with more advanced exposure metrics, is needed to fully elucidate this association.

Diagnosis and management of environmental thoracic emergencies

Physiologic sequelae from increasing ambient pressure in underwater activities, decreasing ambient pressure while at altitude, or the consequences of drowning present a unique set of challenges to emergency physicians. In addition, several environmental toxins cause significant respiratory morbidity, whether they be pulmonary irritants, simple asphyxiants, or systemic toxins. It is important for emergency physicians to understand the pathophysiology of these illnesses as well as to apply this knowledge to the clinical arena either in the prehospital setting or in the emergency department. Current treatment paradigms and controversies within these regimens are discussed.

Occupation and COPD: a brief review

BACKGROUND AND AIMS

This review summarizes the scientific literature relevant to occupational risk factors for chronic obstructive pulmonary disease (COPD).

MATERIAL AND METHODS

This review emphasizes recent work in the field, while placing this in the context of two previous systematic reviews of the subject.

RESULTS

Both the earlier summaries of the literature estimated that the population attributable risk percent (PAR%) of COPD linked to occupational exposures is approximately 15%. More recent studies also strongly support the association between workplace exposures and COPD. Among never smokers, the PAR% for work-related factors may approach 40%. Emerging data also indicate that occupational exposures, at a minimum, are additive to smoking-associated risk of COPD.

CONCLUSIONS

The PAR% for work-related COPD is at least 15%. Scientific significance. The consistency, strength, and plausibility of these data support a causal relationship between occupational exposures and COPD.

Airways obstruction among older construction and trade workers at Department of Energy nuclear sites

BACKGROUND

A study of chronic obstructive pulmonary disease (COPD) among 7,579 current and former workers participating in medical screening programs at Department of Energy (DOE) nuclear weapons facilities through September 2008 was undertaken.

METHODS

Participants provided a detailed work and exposure history and underwent a respiratory examination that included a respiratory history, respiratory symptoms, a posterior-anterior (P-A) chest radiograph classified by International Labour Office (ILO) criteria, and spirometry. Statistical models were developed to generate group-level exposure estimates that were used in multivariate logistic regression analyses to explore the risk of COPD in relation to exposures to asbestos, silica, cement dust, welding, paints, solvents, and dusts/fumes from paint removal. Risk for COPD in the study population was compared to risk for COPD in the general US population as determined in National Health and Nutrition Examination Survey (NHANES III).

RESULTS

The age-standardized prevalence ratio of COPD among DOE workers compared to all NHANES III data was 1.3. Internal analyses found the odds ratio of COPD to range from 1.6 to 3.1 by trade after adjustment for age, race, sex, smoking, and duration of DOE employment. Statistically significant associations were observed for COPD and exposures to asbestos, silica, welding, cement dusts, and some tasks associated with exposures to paints, solvents, and removal of paints.

CONCLUSIONS

Our study of construction workers employed at DOE sites demonstrated increased COPD risk due to occupational exposures and was able to identify specific exposures increasing risk. This study provides additional support for prevention of both smoking and occupational exposures to reduce the burden of COPD among construction workers.

Prevalence of chronic obstructive pulmonary disease in the U.S. working population: an analysis of data from the 1997-2004 National Health Interview Survey

To estimate the prevalence and the population attributable fraction of chronic obstructive pulmonary disease (COPD) in the U.S. adult workers, we analyzed data obtained from the National Health Interview Surveys for the period 1997-2004. The overall COPD prevalence was 4.0% (95% confidence interval [CI] 3.9-4.1%). The prevalence was higher in females (5.4%, 95% CI 5.3-5.6%) than in males (2.8%, 95% CI 2.7-2.9%); in Whites (4.2%, 95% CI 4.1-4.3%) than in Blacks (3.4%, 95% CI 3.1-3.7%) and other races (2.4%, 95% CI 2.1-2.8%). Compared with insurance, real estate and other finance industry, the top three industries associated with significantly higher prevalence odds ratios (PORs) (adjusted for age, sex, race, and smoking) were other educational services (POR = 1.5, 95% CI 1.0-2.3); transportation equipment (POR = 1.4, 95% CI 1.1-1.8); and social services, religious and membership organizations (POR = 1.4, 95% CI 1.1-1.7). Compared with managers and administrators, except public administration occupation, the top three occupations with significantly higher PORs were health service (1.8, 95% CI 1.5-2.1), other protective service (POR = 1.6, 95% CI 1.2-2.2), and material moving equipment operators (POR = 1.6, 95% CI 1.1-2.3). The overall population attributable fraction for association of COPD with employment was 12.2% for industry and 17.4% for occupation. Further studies are needed to determine specific risk factors associated with COPD in industries and occupations with elevated prevalence and POR.

Vapor, dust, and smoke exposure in relation to adult-onset asthma and chronic respiratory symptoms: the Singapore Chinese Health Study

Occupational factors contribute to a significant fraction of respiratory disease and symptoms. The authors evaluated the role of occupational exposures in asthma, chronic bronchitis, and respiratory symptoms in the Singapore Chinese Health Study, a population-based cohort of adults aged 45-74 years at enrollment in 1993-1998. Information on occupations and occupational exposures was collected at enrollment for 52,325 subjects for whom respiratory outcomes were obtained via follow-up interviews in 1999-2004. Exposure to dusts from cotton, wood, metal, minerals, and/or asbestos was associated with nonchronic cough and/or phlegm (odds ratio (OR) = 1.19, 95% confidence interval (CI): 1.08, 1.30), chronic bronchitis (OR = 1.26, 95% CI: 1.01, 1.57), and adult-onset asthma (OR = 1.14, 95% CI: 1.00, 1.30). Cotton dust was the major contributor to respiratory symptoms. Vapor exposure from chemical solvents, dyes, cooling oils, paints, wood preservatives, and/or pesticides was associated with nonchronic cough or phlegm (OR = 1.14, 95% CI: 1.03, 1.27), chronic dry cough (OR = 1.55, 95% CI: 1.19, 2.01), and adult-onset asthma (OR = 1.34, 95% CI: 1.15, 1.56). Chemical solvents, cooling oils, and pesticides were the major contributors to respiratory symptoms. These data support the role of occupational exposures in the etiology of respiratory illness in a population-based cohort in Singapore with a low prevalence of atopic illness.

Chronic Obstructive Pulmonary Disease in Patients Under Age 65: Utilization and Costs From a Managed Care Sample

OBJECTIVES

Chronic obstructive pulmonary disease (COPD) affects all adult age groups, not just elderly males. We assessed the health care utilization and cost impact of COPD in different age groups.

METHODS

We compared burden of illness, utilization, and charges for younger versus older COPD patients and versus age- and gender-matched controls.

RESULTS

A total of 16.9% of patients with COPD were under age 65. Patients with COPD (n=19,338) had higher comorbidity than age-matched controls (n=94,384) across all age groups. Younger patients with COPD had lower comorbidity scores and fewer hospitalizations but more COPD-related emergency services than older patients with COPD. Average COPD-related charges were higher for younger patients. Facility-based care was the cost driver across all age groups.

CONCLUSIONS

COPD is a burden to younger individuals in the workforce, who are likely to be enrolled in a commercial health plan.