Costs of occupational COPD and asthma

Computer-Aided Discovery and Redesign for Respiratory Sensitization: A Tiered Mechanistic Model to Deliver Robust Performance Across a Diverse Chemical Space

Asthma is among the most common occupational diseases with considerable public health and economic costs. Chemicals that induce hypersensitivity in the airways can cause respiratory distress and comorbidities with respiratory infections such as COVID. Robust predictive models for this end point are still elusive due to the lack of an experimental benchmark and the over-reliance of existing in silico tools on structural alerts and structural (vs chemical) similarities. The Computer-Aided Discovery and REdesign (CADRE) platform is a proven strategy for providing robust computational predictions for hazard end points using a tiered hybrid system of expert rules, molecular simulations, and quantum mechanics calculations. The recently developed CADRE model for respiratory sensitization is based on a highly curated data set of structurally diverse chemicals with high-fidelity biological data. The model evaluates absorption kinetics in lung mucosa using Monte Carlo simulations, assigns reactive centers in a molecule and possible biotransformations via expert rules, and determines subsequent reactivity with cell proteins via quantum-mechanics calculations using a multi-tiered regression. The model affords an accuracy above 0.90, with a series of external validations based on literature data in the range of 0.88-0.95. The model is applicable to all low-molecular-weight organics and can inform not only chemical substitution but also chemical redesign to advance development of safer alternatives.

Work absence in patients with asthma and/or COPD: a population-based study

Chronic obstructive pulmonary disease (COPD) and asthma impact on work productivity, but their population-based burden and clinical predictors are understudied. In this observational, real-life study, work absence of 14,383 asthma and/or COPD patients present in the MAJORICA cohort (Spain) was compared with the general population. Using multivariable regression, we studied the association of work absence with demographic and clinical characteristics. Patients with asthma and/or COPD had more work absence than the general population (15.2% vs 8.9%, p < 0.0001). Patients with asthma had more often periods of work absence compared to patients with COPD (16.0% vs 12.8%, p < 0.0001). The number of days absent were, however, less in asthma than in COPD (median: 15 days [IQR: 5–51] vs 39 days [IQR: 13–134], p < 0.001). Patients with asthma–COPD overlap were in between (14.5% with absence; median: 27 days [IQR: 10–82]). Comorbid anxiety, allergic rhinitis, and sleep apnoea were independently associated with more work absence.

Costs of isocyanate-related occupational diseases: A systematic review

Although isocyanates are increasingly used in manufacturing and workplace exposure to isocyanates is widely recognized as one of the most frequent causes for occupational lung and skin diseases, little is known about the economic burden on the affected individual and the society. This study provides an overview on costs of occupational diseases related to isocyanates. We performed a systematic literature search of studies in the electronic databases of the German Institute of Medical Documentation and Information, and the Canadian Centre for Occupational Health and Safety. We extracted the key characteristics of the studies and performed a study quality assessment. We identified eight studies on the costs of illness, of which five focused on occupational lung diseases and three on occupational skin diseases. Further, eight studies calculated loss of income/compensation payments. Out of the 16 identified articles, only two reported costs directly attributable to isocyanate-induced diseases (asthma). Studies were hardly comparable because they differed substantially in their methodological approaches. Moreover, the quality assessment of the studies revealed substantial limitations. While a wide range of isocyanate-related costs was identified, consequences of isocyanate-related occupational diseases were considerable in terms of societal costs and loss of income. In most studies, indirect costs were the main cost driver. There is a need for high-quality cost of illness studies on isocyanate-induced diseases stratified by degree of severity and sex. Such studies provide valuable information to develop preventive strategies and set priorities for measures to lower the burden of professional health risks.

Occupation and task as risk factors for asthma-related outcomes among healthcare workers in New York City

BACKGROUND

Previous studies have suggested an association of asthma onset and exacerbation with cleaning and disinfecting activities in a number of industries, including healthcare. The objective of the current study was to investigate the association of asthma and related outcomes with occupations and tasks in urban healthcare workers in the United States.

METHODS

A questionnaire was implemented in a sample of workers from nine healthcare occupations in New York City. We used regression models to examine the association of post-hire asthma, current asthma, exacerbation of asthma, a symptom algorithm for bronchial hyper-responsiveness (BHR-related symptoms), a symptom-based asthma score, and the symptom wheeze with occupation and four healthcare tasks, while adjusting for other risk factors and potential confounders.

RESULTS

A total of 2030 participants completed the questionnaire. The task of cleaning fixed surfaces was significantly associated with most outcome variables, including current asthma (odds ratio (OR) = 1.84, 95% confidence interval (CI) 1.26-2.68), moderate exacerbation (OR = 3.10, 95% CI 1.25-7.67), and BHR-related symptoms (OR = 1.38, 95% CI 1.08-1.77). In comparison to nursing assistants, the occupations environmental service workers and registered nurses were at higher risk for current asthma, and licensed practical nurses were at higher risk for moderate exacerbation. Other tasks associated with outcomes were administering aerosolized medications with current asthma and moderate exacerbation, and sterilizing medical equipment with BHR-related symptoms.

CONCLUSIONS

These findings add to the growing body of evidence for the association of asthma with cleaning and other activities in healthcare. Further research is especially needed to investigate the association of asthma-related outcomes with exposure metrics based on tasks, products, and chemical exposures in healthcare.

Occupational chronic obstructive pulmonary disease: a standard of care

BACKGROUND

Consistent evidence from population studies report that 10-15% of the total burden of chronic obstructive pulmonary disease (COPD) is associated with workplace exposures. This proportion of COPD could be eliminated if harmful workplace exposures were controlled adequately.

AIMS

To produce a standard of care for clinicians, occupational health professionals, employers and employees on the identification and management of occupational COPD.

METHODS

A systematic literature review was used to identify published data on the prevention, identification and management of occupational COPD. Scottish Intercollegiate Guidance Network grading and the Royal College of General Practitioner three star grading system were used to grade the evidence.

RESULTS

There are a number of specific workplace exposures that are established causes of COPD. Taking an occupational history in patients or workers with possible or established COPD will identify these. Reduction in exposure to vapours, gases, dusts and fumes at work is likely to be the most effective method for reducing occupational COPD. Identification of workers with rapidly declining lung function, irrespective of their specific exposure, is important. Individuals can be identified at work by accurate annual measures of lung function.

CONCLUSIONS

Early identification of cases with COPD is important so that causality can be considered and action taken to reduce causative exposures thereby preventing further harm to the individual and other workers who may be similarly exposed. This can be achieved using a combination of a respiratory questionnaire, accurate lung function measurements and control of exposures in the workplace.

The attributable annual health costs of U.S. occupational lead poisoning

BACKGROUND

U.S. occupational lead standards have not changed for decades, while knowledge about lead's health effects has grown substantially.

OBJECTIVE

The objective of this analysis was twofold: to estimate the attributable annual societal costs of health damages associated with occupationally lead-exposed U.S. workers and, more broadly, to develop methods for a fuller valuation of health damages.

METHODS

I combined data voluntarily reported to NIOSH on the number of highly exposed workers with published literature on the health effects of lead in adults to estimate the potential health benefits of lowering the U.S. occupational limit. I developed simple algorithms for monetizing more fully both the direct medical and indirect (productivity) damages associated with those high lead exposures.

RESULTS

I estimated direct medical costs of $141 million (2014US$) per year for 16 categories of health endpoints, and combined direct and indirect costs of over $392 million (2014US$) per year for the 10,000 or so U.S. workers with high occupational lead exposures.

CONCLUSIONS

Reducing allowable occupational lead limits produces annual societal benefits of almost $40,000 per highly exposed worker. Given underreporting of actual exposures and the omission of important health effects, this is likely a severe underestimate.

The global impact of non-communicable diseases on macro-economic productivity: a systematic review

Non-communicable diseases (NCDs) have large economic impact at multiple levels. To systematically review the literature investigating the economic impact of NCDs [including coronary heart disease (CHD), stroke, type 2 diabetes mellitus (DM), cancer (lung, colon, cervical and breast), chronic obstructive pulmonary disease (COPD) and chronic kidney disease (CKD)] on macro-economic productivity. Systematic search, up to November 6th 2014, of medical databases (Medline, Embase and Google Scholar) without language restrictions. To identify additional publications, we searched the reference lists of retrieved studies and contacted authors in the field. Randomized controlled trials, cohort, case-control, cross-sectional, ecological studies and modelling studies carried out in adults (>18 years old) were included. Two independent reviewers performed all abstract and full text selection. Disagreements were resolved through consensus or consulting a third reviewer. Two independent reviewers extracted data using a predesigned data collection form. Main outcome measure was the impact of the selected NCDs on productivity, measured in DALYs, productivity costs, and labor market participation, including unemployment, return to work and sick leave. From 4542 references, 126 studies met the inclusion criteria, many of which focused on the impact of more than one NCD on productivity. Breast cancer was the most common (n = 45), followed by stroke (n = 31), COPD (n = 24), colon cancer (n = 24), DM (n = 22), lung cancer (n = 16), CVD (n = 15), cervical cancer (n = 7) and CKD (n = 2). Four studies were from the WHO African Region, 52 from the European Region, 53 from the Region of the Americas and 16 from the Western Pacific Region, one from the Eastern Mediterranean Region and none from South East Asia. We found large regional differences in DALYs attributable to NCDs but especially for cervical and lung cancer. Productivity losses in the USA ranged from 88 million US dollars (USD) for COPD to 20.9 billion USD for colon cancer. CHD costs the Australian economy 13.2 billion USD per year. People with DM, COPD and survivors of breast and especially lung cancer are at a higher risk of reduced labor market participation. Overall NCDs generate a large impact on macro-economic productivity in most WHO regions irrespective of continent and income. The absolute global impact in terms of dollars and DALYs remains an elusive challenge due to the wide heterogeneity in the included studies as well as limited information from low- and middle-income countries.

Occupational risk factors for COPD phenotypes in the Multi-Ethnic Study of Atherosclerosis (MESA) Lung Study

INTRODUCTION

The contribution of occupational exposure to the risk of chronic obstructive pulmonary disease COPD in population-based studies is of interest. We compared the performance of self-reported exposure to a newly developed JEM in exposure-response evaluation.

METHODS

We used cross-sectional data from Multi-Ethnic Study of Atherosclerosis (MESA), a population-based sample of 45-84 year olds free of clinical cardiovascular disease at baseline. MESA ascertained the most recent job and employment, and the MESA Lung Study measured spirometry, and occupational exposures for 3686 participants. Associations between health outcomes (spirometry defined airflow limitation and Medical Research Council-defined chronic bronchitis) and occupational exposure [self-reported occupational exposure to vapor-gas, dust, or fumes (VGDF), severity of exposure, and a job-exposure matrix (JEM)-derived score] were evaluated using logistic regression models adjusted for non-occupational risk factors.

RESULTS

The prevalence of airflow limitation was associated with self-reported exposure to vapor-gas (OR 2.6, 95%CI 1.1-2.3), severity of VGDF exposure (P-trend < 0.01), and JEM dust exposure (OR 2.4, 95%CI 1.1-5.0), and with organic dust exposure in females; these associations were generally of greater magnitude among never smokers. The prevalence of chronic bronchitis and wheeze was associated with exposure to VGDF. The association between airflow limitation and the combined effect of smoking and VGDF exposure showed an increasing trend. Self-reported vapor-gas, dust, fumes, years and severity of exposure were associated with increased prevalence of chronic bronchitis and wheeze (P < 0.001).

CONCLUSIONS

Airflow limitation was associated with self-reported VGDF exposure, its severity, and JEM-ascertained dust exposure in smokers and never-smokers in this multiethnic study.

A novel method for estimating the effects of job conditions on asthma and chronic lung disease

OBJECTIVE

This study uses 32 years of longitudinal job history to analyze the long-term effect of exposure to specific workplace conditions on the risk of contracting asthma or chronic lung disease later in life. Our approach allows for the estimation of occupational respiratory risks even in the absence of direct environmental monitoring.

METHODS

We employ a novel methodology utilizing data from the National Longitudinal Survey of Youth 1979 (NLSY79), and ratings of job exposures from the Occupational Information Network (O*NET), which are based on 70 years of empirical data compiled by the U.S. Department of Labor. A series of multivariable logistic regression analyses are performed to determine how long-term exposure to a particular occupational O*NET indicator (e.g., working in an extremely hot or cold environment) is related to asthma and COPD risk.

RESULTS

The risk of contracting COPD was significantly associated with long-term work in very hot or cold temperatures (OR = 1.50, CI: 1.07-2.10), performing physically demanding activities (OR = 1.65, CI:1.20-2.28), working outdoors exposed to weather (OR = 1.45, CI:1.06-1.99), and workplace exposure to contaminants (OR = 1.42, CI:1.05-1.96). In general, the effects of exposure were greater for COPD than for asthma. With respect to contracting asthma, only exposure to work in very hot or cold temperatures (OR = 1.35, CI:1.08-1.70) and performing physically demanding activities (OR = 1.23, CI:1.00-1.52) were statistically significant.

CONCLUSIONS

Use of O*NET job descriptors as surrogate measures of workplace exposures can provide a useful way of analyzing the risk of occupationally-related respiratory disease in situations where direct exposure measurement is not feasible.

Indirect costs in chronic obstructive pulmonary disease: a review of the economic burden on employers and individuals in the United States

Objective

To review and summarize existing literature on the indirect burden of chronic obstructive pulmonary disease (COPD) in the US.

Methods

Medline, Scopus, and OvidSP databases were searched using defined search terms to identify relevant studies. Eligible studies were published in English between January 2000 and April 2012 and calculated the indirect burden of COPD in a US population in terms of prevalence, incidence or costs of productivity loss, disability, morbidity, or mortality.

Results

Of 53 studies identified, eleven met eligibility criteria, with data years spanning 1987–2009. Estimates of workforce participation range from 56% to 69% among individuals with COPD and from 65% to 77% among individuals without COPD. Approximately 13%–18% of those with COPD are limited in the amount or type of work they can do and one-third or more experience general activity limitation. Estimates of restricted activity days range from 27–63 days per year. Estimates of mean annual sick leave and/or disability days among employed individuals with COPD range from 1.3–19.4 days. Estimates of bed confinement range from 13–32 days per year. Estimated mean annual indirect costs were $893–$2,234/person (US dollars) with COPD ($1,521–$3,348 in 2010 [US dollars]) and varied with the population studied, specific cost outcomes, and economic inputs. In studies that assessed total (direct and indirect) costs, indirect costs accounted for 27%–61% of total costs, depending on the population studied.

Conclusions

COPD is associated with substantial indirect costs. The disease places a burden on employers in terms of lost productivity and associated costs and on individuals in terms of lost income related to absenteeism, activity limitation, and disability. Consideration of indirect as well as direct costs is necessary to gain a more complete view of the societal burden of COPD.

Work-related asthma and employment status--38 states and District of Columbia, 2006-2009

OBJECTIVES

To examine differences in current employment status between persons with health professional-diagnosed work-related asthma and non-work-related asthma and to examine factors associated with unemployment in these groups.

METHODS

We analyzed the 2006-2009 Behavioral Risk Factor Surveillance System Asthma Call-back Survey for ever-employed adults (excluding those who were retired, homemakers and students at the time of the interview) with current asthma in 38 states and District of Columbia (N = 25,680). We calculated prevalence ratios (PRs) adjusted for age, sex, race/ethnicity, education and income.

RESULTS

Among adults with current asthma, individuals with work-related asthma were less likely to be currently employed for wages (PR = 0.89; 95% confidence interval [CI] = 0.84-0.95) and more likely to be unable to work (PR = 1.44; 95% CI = 1.24-1.67) than those with non-work-related asthma. Among adults with current asthma who were unemployed at the time of the interview, adults with work-related asthma did not differ from those with non-work-related asthma in naming disability as reason for unemployment (PR = 1.09; 95% CI = 0.94-1.26). However, those with work-related asthma were more likely to be unable to work for health reasons other than disability (PR = 1.46; 95% CI = 1.01-2.12) than adults with non-work-related asthma.

CONCLUSIONS

Additional studies are needed to determine what health reasons prevent individuals with work-related asthma from working and if the health reasons are asthma-related.

Medical surveillance for prevention of occupational asthma

PURPOSE OF REVIEW

Because there is sufficient knowledge of its environmental determinants, occupational asthma is a disease that ought to be largely preventable; yet its incidence in many settings remains unacceptably high. Here we review one approach to prevention: the routine use of health surveillance in exposed workforces.

RECENT FINDINGS

Health surveillance is widely practised but there is little evidence that it is used strategically to reduce disease incidence. There are several barriers to the effective use of its various components, chiefly symptoms questionnaires and spirometry. Cost-benefit analyses may help to increase the uptake of industry-wide workplace interventions.

SUMMARY

The effective use of health surveillance for occupational asthma continues to be challenging and there remains relatively little published evidence that will encourage those involved to use it more efficiently. Useful advances could be made by greater collaboration between employers, employee organizations, legislators and researchers.

Occupational asthma

Occupational asthma is the most common occupational lung disease. Work-aggravated asthma and occupational asthma are two forms of asthma causally related to the workplace, while reactive airways dysfunction syndrome is a separate entity and a subtype of occupational asthma. The diagnosis of occupational asthma is most often made on clinical grounds. The gold standard test, specific inhalation challenge, is rarely used. Low molecular weight isocyanates are the most common compounds that cause occupational asthma. Workers with occupational asthma secondary to low molecular weight agents may not have elevated specific IgE levels. The mechanisms of occupational asthma associated with these compounds are partially described. Not all patients with occupational asthma will improve after removal from the workplace.

Socioeconomic impact of work-related asthma

Work-related asthma (WRA) accounts for 10-15% of adult asthma. This review will summarize the available information related to the socioeconomic outcomes inherent to WRA. A substantial proportion of subjects suffering from WRA experience prolonged work disruption and subsequent loss of income. Moreover, recent studies have established that WRA is associated with a higher use of healthcare resources and a lower quality of life than asthma unrelated to work. The negative socioeconomic consequences are mostly influenced by professional and demographic factors, including reduced possibilities for relocation to an unexposed job within the same company, lack of effective retraining programs and low level of education. These socioeconomic considerations should be regarded as a central component in the implementation of rational management and prevention policies.

Physician-patient communication regarding asthma and work

BACKGROUND

Healthy People 2020-specific respiratory diseases objectives seek to increase the proportion of people with current asthma who receive appropriate asthma care. For adults, this includes a discussion of whether asthma is work-related.

PURPOSE

To establish a baseline measure of physician-patient communication regarding asthma and work.

METHODS

This study used data from 27,157 non-institutionalized U.S. adult respondents of the 2010 National Health Interview Survey (analyzed in 2011). Adults employed at any time in the 12 months prior to the interview with a health-professional diagnosis of current asthma who have been told by a health professional that their asthma was probably work-related or ever discussed the relatedness of asthma and work were identified. Weighted proportions and, using logistic regression analysis, prevalence ORs for factors that may have predicted communication with a health professional regarding an asthma-work relationship were calculated.

RESULTS

An estimated 6.6% (95% CI=5.1%, 8.2%) of employed adults with current asthma have been told that their asthma is work-related. Among those not so informed, 7.4% (95% CI=5.6%, 9.2%) ever discussed the topic. When responses to both questions were considered, the proportion was 13.5% (95% CI=11.3%, 15.8%). Employed adults aged ≥30 years, those reporting adverse asthma outcomes, and those of Hispanic ethnicity had higher odds of having communication with a health professional about the relation between their asthma and their work.

CONCLUSIONS

One in seven employed adults with asthma report communicating with their health professional about the role of workplace exposures in their asthma. Opportunities to increase this dialogue should be examined.

[Prevention of COPD exacerbation: a fundamental challenge]

INTRODUCTION

Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are a cause of suffering for patients and a burden for healthcare systems and society. Their prevention represents individual and collective challenge. The present article is based on the work of a group of experts who met on 5th and 6th May 2011 and seeks to highlight the importance of AECOPD.

STATE OF THE ART

In the absence of easily quantifiable criteria, the definition of AECOPD varies in the literature, making identification difficult and affecting interpretation of study results. Exacerbations increase mortality and risk of cardiovascular disease. They also increase the risk of developing further exacerbations, accelerate the decline in lung function and contribute to reduction in muscle mass. By limiting physical activity and affecting mental state (anxiety, depression), AECOPD are disabling and impair quality of life. They increase work absenteeism and are responsible for about 60% of the global cost of COPD.

PERSPECTIVES

Earlier identification with simple criteria, possibly associated to patient phenotyping, could be helpful in preventing hospitalization.

CONCLUSIONS

Given their immediate and delayed impact, AECOPD should not be trivialized or neglected. Their prevention is a fundamental issue.

Microfluidic paper-based analytical device for particulate metals

A microfluidic paper-based analytical device (μPAD) fabricated by wax printing was designed to assess occupational exposure to metal-containing aerosols. This method employs rapid digestion of particulate metals using microliters of acid added directly to a punch taken from an air sampling filter. Punches were then placed on a μPAD, and digested metals were transported to detection reservoirs upon addition of water. These reservoirs contained reagents for colorimetric detection of Fe, Cu, and Ni. Dried buffer components were used to set the optimal pH in each detection reservoir, while precomplexation agents were deposited in the channels between the sample and detection zones to minimize interferences from competing metals. Metal concentrations were quantified from color intensity images using a scanner in conjunction with image processing software. Reproducible, log-linear calibration curves were generated for each metal, with method detection limits ranging from 1.0 to 1.5 μg for each metal (i.e., total mass present on the μPAD). Finally, a standard incineration ash sample was aerosolized, collected on filters, and analyzed for the three metals of interest. Analysis of this collected aerosol sample using a μPAD showed good correlation with known amounts of the metals present in the sample. This technology can provide rapid assessment of particulate metal concentrations at or below current regulatory limits and at dramatically reduced cost.

Work-related asthma, financial barriers to asthma care, and adverse asthma outcomes: asthma call-back survey, 37 states and District of Columbia, 2006 to 2008

BACKGROUND

Proper asthma management and control depend on patients having affordable access to healthcare yet financial barriers to asthma care are common.

OBJECTIVE

To examine associations of work-related asthma (WRA) with financial barriers to asthma care and adverse asthma outcomes.

RESEARCH DESIGN

Cross-sectional, random-digit-dial survey conducted in 37 states and District of Columbia.

SUBJECTS

A total of 27,927 ever-employed adults aged ≥18 years with current asthma.

MEASURES

Prevalence ratios (PR) for the associations of WRA with financial barriers to asthma care and of WRA with adverse asthma outcomes stratified by financial barriers.

RESULTS

Persons with WRA were significantly more likely than those with non-WRA to have at least 1 financial barrier to asthma care [PR, 1.66; 95% confidence interval (CI), 1.43-1.92]. Individuals with WRA were more likely to experience adverse asthma outcomes such as asthma attack (PR, 1.31; 95% CI, 1.22-1.40), urgent treatment for worsening asthma (PR, 1.57; 95% CI, 1.39-1.78), asthma-related emergency room visit (PR, 1.69; 95% CI, 1.41-2.03), and very poorly controlled asthma (PR, 1.54; 95% CI: 1.36-1.75). After stratifying for financial barriers to asthma care, the associations did not change.

CONCLUSIONS

Financial barriers to asthma care should be considered in asthma management, and individuals with WRA are more likely to experience financial barriers. However, individuals with WRA are more likely to experience adverse asthma outcomes than individuals with non-WRA, regardless of financial barriers. Additional studies are needed to identify medical, behavioral, occupational, or environmental factors associated with adverse asthma outcomes among individuals with WRA.

Health outcomes associated with lung function decline and respiratory symptoms and disease in a community cohort

BACKGROUND

In workplace respiratory disease prevention, a thorough understanding is needed of the relative contributions of lung function loss and respiratory symptoms in predicting adverse health outcomes.

METHODS

Copenhagen City Heart Study respiratory data collected at 4 examinations (1976-2003) and morbidity and mortality data were used to investigate these relationships. With 15 or more years of follow-up for a hospital diagnosis of chronic obstructive pulmonary disease (COPD) morbidity, COPD or coronary heart disease (CHD) mortality, and all-cause mortality, risks for these outcomes were estimated in relation to asthma, chronic bronchitis, shortness of breath, and lung function level at examination 2 (1981-1983) or lung function decline established from examinations 1 (1976-1978) to 2 using 4 measures (FEV(1) slope, FEV(1) relative slope, American College of Occupational and Environmental Medicine's Longitudinal Normal Limit [LNL], or a limit of 90 milliliters per year [ml/yr]). These risks were estimated by hazard ratios (HR) and 95% confidence intervals (CI) adjusted for age, height-adjusted baseline forced expiratory volume in 1 second (FEV(1)/height(2)), and height.

RESULTS

For COPD morbidity, the increasing trend in the HR (95% CI) by quartiles of the FEV(1) slope reached a maximum of 3.77 (2.76-5.15) for males, 6.12 (4.63-8.10) for females, and 4.14 (1.57-10.90) for never-smokers. Significant increasing trends were also observed for mortality, with females at higher risk.

CONCLUSION

Lung function decline was associated with increased risk of COPD morbidity and mortality emphasizing the need to monitor lung function change over time in at-risk occupational populations.

Geographic disparities in chronic obstructive pulmonary disease (COPD) hospitalization among Medicare beneficiaries in the United States

Background:

Hospitalizations for persons with chronic obstructive pulmonary disease (COPD) result in significant health care resource use and excess expenditures. Despite well-documented sociodemographic disparities in COPD outcomes, no study has characterized geographic variations in COPD hospitalization across the US.

Methods:

Almost 3.8 million COPD hospitalization records were extracted from Medicare claims for 1995–2006, and the total population of eligible Medicare beneficiaries was extracted from the Medicare enrollment records to calculate COPD hospitalization rates by Health Service Area (HSA), (n = 949). Spatial cluster analysis and Bayesian hierarchical spatial modeling were used to characterize the geography of COPD hospitalizations.

Results:

The overall COPD hospitalization rate was 11.30 per 1,000 beneficiaries for the aggregated period 1995–2006. HSA-level COPD hospitalization rates had a median of 11.7 and a range of 3.0 (Cache, UT) to 76.3 (Pike, KY). Excessive hospitalization risk was concentrated in Appalachia, the southern Great Lakes, the Mississippi Delta, the Deep South, and west Texas. In the Bayesian spatial mixture model, 73% of variability of COPD hospitalization relative risk was attributed to unidentified regional social and physical environments shared by HSAs rather than to unique local HSA factors (27%).

Conclusion:

We discovered distinct geographic patterns in COPD hospitalization rates and risks attributed to both regionally-shared environmental risk factors and HSA-unique environmental contexts. The correlates of these geographic patterns remain to be determined. Geographic comparisons of COPD hospitalization risk provide insights for better public health practice, policies, and programs for COPD prevention.

Chronic Obstructive Pulmonary Disease and Smoking Cessation

Chronic obstructive pulmonary disease (COPD) is a major and increasing cause of morbidity and mortality. Cigarette smoking is the most important risk factor for COPD, and smoking cessation is, in most cases, the most effective way of preventing the onset and progression of COPD. The purpose of the present article was to review the current state of interventions for smokers with COPD. Because 70% of smokers visit a physician annually, primary care providers play a key role in the counseling of all patients at every visit. If smoking cessation is achieved at an early stage of disease, it is associated with a decrease in pulmonary symptoms and improves prognosis and prolonged abstinence. The health benefits of smoking cessation are immediate and substantial, and interventions provided for smokers suggest that multiple modalities are needed. Smoking cessation counseling in combination with nicotine replacement therapy (NRT) appears to be the most effective modality followed by smoking cessation in combination with an antidepressant to enhance prolonged abstinence.

Spirometry Longitudinal Data Analysis Software (SPIROLA) for Analysis of Spirometry Data in Workplace Prevention or COPD Treatment

Chronic obstructive pulmonary disease (COPD) is one of the leading causes of morbidity and mortality. Periodic spirometry is often recommended for individuals with potential occupational exposure to respiratory hazards and in medical treatment of respiratory disease, to prevent COPD or improve treatment outcome. To achieve the full potential of spirometry monitoring in preserving lung function, it is important to maintain acceptable precision of the longitudinal measurements, apply interpretive strategies that identify individuals with abnormal test results or excessive loss of lung function in a timely manner, and use the results for intervention on respiratory disease prevention or treatment modification. We describe novel, easy-to-use visual and analytical software, Spirometry Longitudinal Data Analysis software (SPIROLA), designed to assist healthcare providers in the above aspects of spirometry monitoring. Software application in ongoing workplace spirometry-based medical monitoring programs helped to identify increased spirometry data variability due to deteriorating test quality and subsequent improvement following interventions, and helped to enhance identification of individuals with excessive decline in lung function.

Occupational and work-exacerbated asthma: similarities and differences

Over the years, there have been tremendous efforts to improve the understanding of occupational asthma (OA), whereas work-exacerbated asthma (WEA) has been somewhat overlooked. The aim of this work is to review the literature, comparing the prevalence of OA and WEA, their clinical and inflammatory characteristics, as well as the work environment of those suffering from OA and WEA. We performed a PubMed search up to September 2006 using the keywords: work-related asthma, WEA, work-aggravated asthma and OA. Only studies in English were included for consideration. We found that OA and WEA are prevalent conditions. The characteristics of subjects with OA and WEA vary according to the type of studies undertaken to describe these conditions. Many sensitizing agents have been reported to cause OA, whereas exposures to irritant agents seem to be associated with the occurrence of WEA. The inflammatory profile may differ between these two conditions, but the data are too limited and sometimes too contradictory to allow a firm conclusion to be drawn. The socioeconomic outcome of these conditions seems similar. Therefore, further studies investigating the prevalence of WEA, as well as its clinical, functional and inflammatory characteristics, are needed to improve the management of the workers with WEA.

Surveillance of work-related asthma in new york state

OBJECTIVE

The objective of this paper is to determine the percent of adults with asthma attributable to work and describe characteristics of the work-related asthma population in New York State. Sociodemographic and control characteristics of those with and without work-related asthma are compared.

METHODS

Data from three population-based surveys and one case-based surveillance system were analyzed. Work-relatedness of asthma was determined by self-report for the population-based surveys and by physician report for the case-based system. Self-reported sociodemographic and control characteristics were analyzed for the population-based surveys by work-relatedness.

RESULTS

The percent of work-relatedness among adults with current asthma in New York State ranged from 10.6% to 44.5%. Significantly more adults with work-related asthma had poorly controlled asthma than those without work-related asthma. More adults with work-related asthma also tended to be employed in the manufacturing, educational services, and public administration industries than the general population. The most frequently reported exposure was dust.

CONCLUSIONS

Adults with work-related asthma have decreased control and adverse socioeconomic impacts compared to those with asthma that is not work-related. Increased recognition and physician reporting is necessary to further prevent the impact of work-related exposures.

Burden of community-acquired pneumonia in North American adults

To determine the burden of community-acquired pneumonia (CAP) affecting adults in North America, a comprehensive literature review was conducted to examine the incidence, morbidity and mortality, etiology, antibiotic resistance, and economic impact of CAP in this population. In the United States, there were approximately 4.2 million ambulatory care visits for pneumonia in 2006. Pneumonia and influenza continue to be a common cause of death in the United States (ranked eighth) and Canada (ranked seventh). In 2005, there were >60,000 deaths due to pneumonia in persons aged>or=15 years in the United States alone. The hospitalization rate for all infectious diseases increased from 1525 hospitalizations per 100 000 persons in 1998 to 1667 per 100 000 persons in 2005. Admission to an intensive care unit was required in 10% to 20% of patients hospitalized with pneumonia. The mean length of stay for pneumonia was >or=5 days and the 30-day rehospitalization rate was as high as 20%. Mortality was highest for CAP patients who were hospitalized; the 30-day mortality rate was as high as 23%. All-cause mortality for CAP patients was as high as 28% within 1 year. Streptococcus pneumoniae continues to be the most frequently identified pathogen associated with CAP, and pneumococcal resistance to antimicrobials may make treatment more difficult. The economic burden associated with CAP remains substantial at >$17 billion annually in the United States. Despite the availability and widespread adherence to recommended treatment guidelines, CAP continues to present a significant burden in adults. Furthermore, given the aging population in North America, clinicians can expect to encounter an increasing number of adult patients with CAP. Given the significance of the disease burden, the potential benefit of pneumococcal vaccination in adults is substantial.

Recognition and surveillance of occupational asthma: a preventable illness with missed opportunities

Occupational asthma is common, disabling and costly, and it is often difficult to diagnose. Incidence statistics are consequently unreliable, and there are formidable difficulties in recognizing and managing what should be a preventable illness. The opportunities have largely been missed. The author offers a personal view of what, ideally, should be done--recognizing that at present the ideal is not readily practical. Always consider the possibility of an occupational cause at the time adult-onset asthma is first recognized-the probability of this is of the order 9-15%. Do not prescribe treatment unless this possibility is remote or the asthma is life-threatening. If the possibility is not remote seek immediate advice from a specialized centre, without prescribing masking medication and without curtailing usual work practice. The specialized referral centre should place the accurate measurement of airway responsiveness at the centre of investigatory strategies. A return-to-work study, monitored by serial measurements of airway responsiveness and ventilatory function, provides adequate objective evidence for diagnosis in most cases. When a novel cause is suspected, specific inhalation provocation testing with the particular agent in the specialized centre is desirable. Regular competent surveillance is necessary in high-risk occupational environments; this should include environmental monitoring, the detection of relevant new symptoms, spirometry measurements, serum antibody studies (where available) and a robust protocol for managing inevitable failed attendances.

Prevalence of lifetime asthma and current asthma attacks in U.S. working adults: an analysis of the 1997-2004 National Health Interview Survey data

OBJECTIVE

To estimate national prevalences of lifetime asthma and asthma attacks among workers by age, sex, race, occupation and industry, and estimate population attributable fraction to employment for asthma attacks in the United States.

METHODS

The 1997-2004 National Health Interview Survey data for currently working adults aged > or = 18 years were analyzed.

RESULTS

Lifetime asthma prevalence was 9.2%; the social services religious and membership organizations industry and the health service occupation had the highest asthma prevalence. Asthma attack prevalence among workers with asthma was 35.4%; the primary metal industry and the health assessment and treating occupation had the highest attack prevalence. Approximately, 5.9% of cases reporting an asthma attack were attributed to employment when considering industries and 3.8% when considering occupations.

CONCLUSIONS

Future studies and intervention strategies should address the higher prevalence of asthma in certain industries and occupations.

Mortality from infectious pneumonia in metal workers: a comparison with deaths from asthma in occupations exposed to respiratory sensitisers

BACKGROUND

National analyses of mortality in England and Wales have repeatedly shown excess deaths from pneumonia in welders. During 1979-90 the excess was attributable largely to deaths from lobar pneumonia and pneumonias other than bronchopneumonia, limited to men of working age and apparent in other occupations with exposure to metal fumes. The findings for 1991-2000 were assessed and compared with the mortality pattern from asthma in occupations exposed to known respiratory sensitisers.

METHODS

The Office of National Statistics supplied data on deaths by underlying cause among men aged 16-74 years in England and Wales during 1991-2000, including age and last held occupation. Data were abstracted on pneumonia for occupations with exposure to metal fumes and on asthma for occupations commonly reported to surveillance schemes as at risk of occupational asthma. The expected numbers of deaths were estimated by applying age-specific proportions of deaths by cause in the population to the total deaths by age in each occupational group. Observed and expected numbers were compared for each cause of death.

RESULTS

Among men of working age in occupations with exposure to metal fumes there was excess mortality from pneumococcal and lobar pneumonia (54 deaths vs 27.3 expected) and from pneumonias other than bronchopneumonia (71 vs 52.4), but no excess from these causes at older ages or from bronchopneumonia at any age. The attributable mortality from metal fume exposure was 45.3 excess deaths compared with an estimated 62.6 deaths from occupational asthma.

CONCLUSION

Exposure to metal fumes is a material cause of occupational mortality. The hazard deserves far more attention than it presently receives.

Assessment of the Economic Burden of COPD in the U.S.: A Review and Synthesis of the Literature

The costs of chronic obstructive pulmonary disease (COPD) pose a major economic burden to the United States. Studies evaluating COPD costs have generated widely variable estimates; we summarized and critically compared recent estimates of the annual national and per-patient costs of COPD in the U.S. Thirteen articles reporting comprehensive estimates of the direct costs of COPD (costs related to the provision of medical goods and services) were identified from searches of relevant primary literature published since 1995. Few papers reported indirect costs of COPD (lost work and productivity). The National Heart, Lung, and Blood Institute (NHLBI) provides the single current estimate of the total (direct plus indirect) annual cost of COPD to the U.S., $38.8 billion in 2005 dollars. More than half of this cost ($21.8 billion) was direct, aligning with the $20-26 billion range reported by two other recent analyses of large national datasets. For per-patient direct costs (in $US 2005), studies using recent data yield attributable cost estimates (costs deemed to be related to COPD) in the range of $2,700-$5,900 annually, and excess cost estimates (total costs incurred by COPD patients minus total costs incurred by non-COPD patients) in the range of $6,100-$6,600 annually. Studies of both national and per-patient costs that use data approximately 8-10 years old or older have produced estimates that tend to deviate from these ranges. Cost-of-illness studies using recent data underscore the substantial current cost burden of COPD in the U.S.

Optimizing economic outcomes in the management of COPD

Attention to COPD is increasing worldwide because its high prevalence, morbidity, and mortality present a challenging problem for all healthcare systems. The burden of COPD, which is usually measured in terms of progressive lung function decline, impact on patients' symptoms, patient's disability, and quality of life, together with the corresponding use of health care resources, is still a major aspect of the disease. Recommendations to treat COPD according to the most accepted guidelines have expanded in recent years even though COPD still remains unacceptably under-diagnosed and under-treated worldwide. Obviously, more severe degrees of COPD receive major attention both in terms of monitoring of clinical outcomes and of assessing the economic value of therapeutic interventions. The role of different strategies against COPD should be valued on the basis of their effectiveness in outcome optimization, which primarily depends on the efficacy of prevention activities and of early diagnosis programs. It is generally agreed that the main proportion of COPD burden still depends on the clinically uncontrolled disease and on its high exacerbation rate, which frequently leads to the patient hospitalization. In COPD, the effects of guideline recommendations have been only sporadically investigated in pharmaoeconomic terms, even though symptoms and disability have declined substantially; the corresponding improvement in quality of life, and a significant decrease in both direct and indirect costs have been proved to depend on appropriate rehabilitative and pharmacological long-term treatment of the disease. At present, more precise indices and more fitting outcomes are continuously sought and found in order to assess more effective strategies for controlling COPD.

The direct medical costs of undiagnosed chronic obstructive pulmonary disease

OBJECTIVE

To estimate the costs of undiagnosed chronic obstructive pulmonary disease (COPD) by describing inpatient, outpatient, and pharmacy utilization in the years before and after the diagnosis.

METHODS

A total of 6,864 patients who were enrolled in the Lovelace Health Plan for at least 12 months during the study period (January 1, 1999 through December 31, 2004) were identified. The first date that utilization was attributed to COPD was considered the first date of diagnosis. Each COPD case was matched to up to three age- and sex-matched controls. All utilization and direct medical costs during the study period were compiled monthly and compared based on the time before and after the initial diagnosis.

RESULTS

Total costs were higher by an average of $1,182 per patient in the 2 years before the initial COPD diagnosis, and $2,489 in the 12 months just before the initial diagnosis, compared to matched controls. Most of the higher cost for undiagnosed COPD was attributable to hospitalizations. Inpatient costs did not increase after the diagnosis was made, but approximately one-third of admissions after the diagnosis were attributed to respiratory disease. Outpatient and pharmacy costs did not differ substantially between cases and matched controls until just a few months before the initial diagnosis, but remained 50% to 100% higher than for controls in the 2 years after diagnosis.

CONCLUSIONS

Undiagnosed COPD has a substantial impact on health-care costs and utilization in this integrated managed care system, particularly for hospitalizations.

Quality control chart method for analyzing PEF variability in occupational asthma

BACKGROUND

Asthma is the most common occupational respiratory disorder in the industrialized world. In this research we investigated the effectiveness of quality control chart as a method to explore the work-relatedness of asthma using peak expiratory flow (PEF) as the variable of interest.

METHOD

PEF measurements were recorded from several workers suspected of having occupational asthma. The measurements were recorded for a period of 2 weeks at work and two away from work. For each subject, average [symbol: see text] quality control chart was developed and analyzed using Shewhart methods.

RESULTS

Using the ratio of average daily PEF diurnal variation at work to the baseline average diurnal variation, quality control chart detected and characterized increased variation in PEF between the periods at workplace and away from workplace. This ratio was evaluated at 15% and 20% and compared to the results of the gold standard. A ratio of greater than 15% produced a sensitivity of 94% and specificity of 61%. These results are as good as and in some cases better than the previously published work.

CONCLUSIONS

Quality control chart is an effective and inexpensive method for early intervention to detect workers suspected for occupational asthma. Also, the findings in this article are an invitation for further research in occupational asthma using quality control chart methods for other indices of airways obstruction (FEV-1, RAW) or inflammation (NO).

Work-related asthma in the educational services industry: California, Massachusetts, Michigan, and New Jersey, 1993-2000

OBJECTIVES

To characterize work-related asthma (WRA) cases working in the educational services industry identified by state-based occupational disease surveillance systems.

METHODS

We examined 2,995 WRA cases reported from 1993 to 2000 to four states: California, Massachusetts, Michigan, and New Jersey.

RESULTS

A total of 265 (9%) WRA cases were employed in the educational services industry; 69% of cases were classified as new-onset asthma and 31% as work-aggravated asthma. New-onset asthma cases were further classified as occupational asthma (61%) or as reactive airways dysfunction syndrome (8%). The most frequently reported occupation was teachers and teachers' aides (54%). The most frequently reported agents were indoor air pollutants (28%), unspecified mold (16%), dusts (14%), and cleaning products (7%).

CONCLUSIONS

Asthma within the educational services industry is an occupational health problem. The health of school employees should also be considered when initiatives addressing asthma among schoolchildren are instituted. The identification, elimination, and/or control of respiratory hazards are important factors for the protection of staff and students alike.

Controlling occupational allergies in the workplace

OBJECTIVES

In recent years, the prevalence of work-related asthma has increased. Therefore, more attention needs to be paid to occupational allergens and their avoidance and control in workplaces. However, risk assessment of occupational allergen exposure is difficult because the relationship between exposure concentration, sensitization, and symptoms has not been fully established. This paper introduces a systematic and comprehensive approach to assessing and managing allergen risks at workplaces.

MATERIALS AND METHODS

This approach relies on the cooperation and active communication during the whole process between management, employees, and health care personnel, with the assistance of experts when needed. In addition to gathering background information, including allergic symptoms, through questionnaires addressed to the management and employees, hazard identification is also processed in the workplace through observations and measurements. The methods generally recommended to reduce allergen exposure are compared with those used in the workplace. The process is to be carefully planned and documented to allow later follow-up and re-evaluation.

RESULTS

The multi-faceted approach encompasses several risk assessment techniques, and reveals the prevalence of work-related allergic symptoms. The process effectively focuses on the potential means for controlling allergen exposure.

CONCLUSION

Based on this approach, the synopsis on the critical points that require implementation of effective control measures can be presented.

Cost-effectiveness of various diagnostic approaches for occupational asthma

BACKGROUND

Diagnosis of occupational asthma (OA) by specific inhalation challenge (SIC) can be costly and is not always available. The use of sputum testing to avoid this in some patients may be a more cost-effective alternative.

OBJECTIVES

To compare the cost-effectiveness of SIC with serial measurements of sputum cell counts (sputum testing) and peak expiratory flow (PEF) monitoring.

METHODS

Clinical data and testing costs for OA in 49 patients were collected during a previously published trial, modelled and compared using TreeAge Pro. Clinical outcome was the percentage of accurately diagnosed patients, using SIC as the gold standard. The PEF approach used the most accurate assessment of five experts who were blinded to SIC results. Differences in the proportion of eosinophils during periods on and off work were used for the sputum testing approach and in PEF/sputum for the combined approach. Unit costs were estimated from charges in Canadian hospitals. Data were analyzed by one-way and two-way analyses, and by probabilistic sensitivity analysis using a Monte Carlo simulation technique.

RESULTS

The PEF approach had an estimated accuracy of 52% and cost $365 per patient tested. Compared with PEF monitoring, sputum testing was more accurate and cost an estimated $255 for each additional OA patient correctly diagnosed. SIC costs per additional correct diagnosis were $11,032 compared with sputum testing and $6,458 compared with PEF monitoring. The combined PEF/sputum testing approach was not cost-effective in the base case analysis, but cannot be excluded according to probabilistic sensitivity analyses.

CONCLUSIONS

Although SIC remains the reference test to diagnose OA, when this test is not available, sputum testing is a cost-effective alternative to PEF for diagnosis of OA.

[Epidemiology and etiologic agents of occupational asthma]

INTRODUCTION

Occupational asthma is, by definition, a disease that can be prevented through appropriate protective strategies. Epidemiological information is required to guide these interventions, and we here examine epidemiological data on the burden, causes, and risk factors for this condition.

STATE OF THE ART

Population-based surveys indicate that approximately 15% of adult asthma is attributable to the workplace environment. The most common occupational agents implicated include flour, isocyanates, latex, and persulphate salts. The occupations in which occupational asthma has been most commonly reported are bakers, spray painters, health-care workers, hairdressers, and cleaners. The level of exposure to sensitizing agents seems to be the most relevant risk factor. Atopy is a significant risk factor only for the development of sensitization to high molecular weight agents. The role of other individual determinants, such as genetic factors, has been less consistently established. Occupational asthma is associated with a substantial adverse impact on the employment and financial status of affected workers.

PERSPECTIVES

Methodological improvements are required in order to distinguish more accurately between occupational and work-exacerbated asthma. Further investigations of the effectiveness of primary and secondary preventive interventions are also needed.

Socioeconomic outcomes in work-exacerbated asthma

PURPOSE OF REVIEW

Work-exacerbated asthma has received little attention until recent years, although it is likely that the condition has a considerable societal impact because of its high prevalence. The purpose of this review is to provide a critical analysis of recently published data pertaining to the socioeconomic outcomes of work-exacerbated asthma.

RECENT FINDINGS

Recent data have confirmed that work-exacerbated asthma is associated with a similar impact on work productivity and earning capacity as immunologically mediated occupational asthma. The specific impact of work-exacerbated asthma on these outcomes should be further distinguished from the consequences of asthma unrelated to work. There is some suggestion that work-exacerbated asthma might be associated with higher rates of symptoms and exacerbations when compared with asthma unrelated to work. The impact of work-exacerbated asthma in terms of disease severity and healthcare utilization should therefore be further characterized.

SUMMARY

The socioeconomic impact of work-exacerbated asthma should be taken into account in the management of this common, although often underestimated, condition. In addition, evaluating the economic burden of work-exacerbated asthma and its various components is a key step in implementing cost-effective prevention policies.

Extent, patterns, and burden of uncontrolled disease in severe or difficult-to-treat asthma

BACKGROUND

Characterization of uncontrolled asthma burden in a natural treatment setting can influence treatment recommendations and clinical practice. The objective was to characterize and compare the economic burden of severe or difficult-to-treat asthma in uncontrolled and controlled patients.

METHODS

Baseline patient data (age > or = 13 years; n = 3916) were obtained from The Epidemiology and Natural History of Asthma: Outcomes and Treatment Regimens study. Disease control was assessed using two approaches: (i) applying criteria for control based on the Gaining Optimal Asthma Control study, and (ii) using the Asthma Therapy Assessment Questionnaire (ATAQ) to identify the number of asthma control problems. Assessments were performed at baseline, and at months 12 and 24. Monetary values were assigned to productivity loss and medical resource use. Direct and indirect costs were aggregated over 24 months and compared using Student's t-test for continuous measures and chi-squared for categorical variables.

RESULTS

Throughout the study, most patients had uncontrolled asthma (83% uncontrolled; 16% inconsistent control; 1.3% controlled). Controlled patients experienced fewer work or school absences and less healthcare resource use than uncontrolled patients at all study time points. Using the multilevel ATAQ control score, asthma costs increased directly with the number of asthma control problems. Costs for uncontrolled patients were more than double those of controlled patients throughout the study (14,212 vs 6,452 US Dollars; adjusted to 2002 Dollars; P < 0.0001).

CONCLUSIONS

This study demonstrated that few severe or difficult-to-treat asthma patients achieved control over a 2-year period and the economic consequence of uncontrolled disease is substantial.

Doença pulmonar obstrutiva crônica ocupacional

A doença pulmonar obstrutiva crônica ocupacional, apesar de ampla discussão há quase meio século, ainda é muito pouco abordada em nosso meio. Diversos estudos, especialmente os de base populacional, revelaram a associação entre as exposições ocupacionais aos aerodispersóides e o comprometimento das vias aéreas. Este capítulo objetiva alertar para o diagnóstico da doença pulmonar obstrutiva crônica de origem ocupacional apresentando uma revisão suscinta sobre o tema que deverá ser incorporado ao projeto Global Initiative for Chronic Obstructive Lung Disease, tanto no seu escopo de fundamentação diagnóstica quanto em seu questionário específico. O detalhamento da história ocupacional e a caracterização da exposição a agentes inalatórios, de reconhecida ação deletéria para o aparelho respiratório, seguramente proporcionarão uma melhor abordagem para o reconhecimento, prognóstico e controle dessa doença.

Control chart for monitoring occupational asthma

INTRODUCTION

Work-related asthma has become the most prevalent occupational respiratory disease in the developed world. Occupational asthma is thought to affect 5%-10% of people worldwide. The first step in the diagnosis of occupational asthma is to establish work-relatedness. Although considerable research has been conducted in the area of occupational asthma, no simple, effective, and statistically sound method has been developed that can be used as an initial step to effectively identify the workers at risk for occupational asthma. The purpose of this research was to investigate whether Shewhart control chart method can be used as an effective method to detect occupational asthma.

METHOD

Forty-five workers who completed the study and provided usable peak expiratory flow (a lung function marker) recordings while at work and away from work were included in this study. Control charts were developed using Shewhart's Method. The lower control limit of at work control chart (LCL(W)) was compared to each subject's Personal Best (PB) value.

RESULTS

Reviewing the results of this comparison showed LCL(W)<60% PB to have a sensitivity of 85.71%, specificity of 87.50%, and an error rate of 13.33%. When the subjects suspected for false positive and false negative diagnoses were identified, the test produced a sensitivity of 95.24%, a specificity of 95.83% and an error rate of 4.44%.

CONCLUSIONS

Our results were as good as, and in some cases better than, published clinical guidelines.

IMPACT ON INDUSTRY

Our research showed that the control chart method is an effective, simple, and inexpensive tool for early intervention in workers suspected for occupational asthma.

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.

Characterizing the Burden of Occupational Injury and Disease

OBJECTIVES

To review the literature on the burden of occupational disease and injury and to provide a comprehensive characterization of the burden.

METHODS

The scientific and governmental literature from 1990 to the present was searched and evaluated. Thirty-eight studies illustrative of the burden of occupational disease were reviewed for findings, methodology, strengths, and limitations.

RESULTS

Recent U.S. estimates of occupational mortality and morbidity include approximately 55,000 deaths (eighth leading cause) and 3.8 million disabling injuries per year, respectively. Comprehensive estimates of U.S. costs related to these burdens range between dollar 128 billion and dollar 155 billion per year. Despite these significant indicators, occupational morbidity, mortality, and risks are not well characterized in comparative burden assessments.

CONCLUSIONS

The magnitude of occupational disease and injury burden is significant but underestimated. There is a need for an integrated approach to address these underestimates.