Occupational asthma: review of assessment, treatment, and compensation

Smart Devices Are Poised to Revolutionize the Usefulness of Respiratory Sounds

The association between breathing sounds and respiratory health or disease has been exceptionally useful in the practice of medicine since the advent of the stethoscope. Remote patient monitoring technology and artificial intelligence offer the potential to develop practical means of assessing respiratory function or dysfunction through continuous assessment of breathing sounds when patients are at home, at work, or even asleep. Automated reports such as cough counts or the percentage of the breathing cycles containing wheezes can be delivered to a practitioner via secure electronic means or returned to the clinical office at the first opportunity. This has not previously been possible. The four respiratory sounds that most lend themselves to this technology are wheezes, to detect breakthrough asthma at night and even occupational asthma when a patient is at work; snoring as an indicator of OSA or adequacy of CPAP settings; cough in which long-term recording can objectively assess treatment adequacy; and crackles, which, although subtle and often overlooked, can contain important clinical information when appearing in a home recording. In recent years, a flurry of publications in the engineering literature described construction, usage, and testing outcomes of such devices. Little of this has appeared in the medical literature. The potential value of this technology for pulmonary medicine is compelling. We expect that these tiny, smart devices soon will allow us to address clinical questions that occur away from the clinic.

Parental occupational exposures prior to conception and offspring wheeze and eczema during first year of life

PURPOSE

Parental exposures prior to conception might influence asthma and allergy risk in offspring. As occupational exposures are established risk factors for asthma and allergies, we investigated if parental occupational exposures prior to conception cause wheeze and eczema in offspring during the first year of life.

METHODS

We analysed data of 436 families from an offspring cohort based on a follow-up study of German participants of the International Study of Asthma and Allergies in Childhood (ISAAC). Offspring cohort data was collected between 2009 and 2019. Occupational exposures were based on participants' work histories and measured by a Job-Exposure-Matrix. We used Bayesian logistic regression models for analysis. Inference and confounder selection were based on directed acyclic graphs.

RESULTS

In mothers, for both allergic and irritative occupational exposures prior to conception suggestive effects on offspring eczema during the first year of life were found (allergens: odds ratio (OR) 1.22, 95% compatibility interval (CI) 0.92-1.57; irritants: OR 1.36, 95% CI 0.99-1.77), while no relation with wheeze was suggested.

CONCLUSIONS

Our results suggest that reduction of asthma-related occupational exposures might not only reduce the burden of disease for occupationally induced or aggravated asthma and allergies in employees but also in their children.

Trajectories of asthma and allergy symptoms from childhood to adulthood

BACKGROUND

Phenotypes of asthma and allergic diseases are mainly studied separately for children and adults. To explore the role of adolescence and young adulthood, we investigated symptom trajectories at the transition from childhood into adulthood.

METHODS

Latent class analysis (LCA) was conducted in a population initially recruited for the German arm of Phase II of the International Study of Asthma and Allergies in Childhood and followed-up three times until their early 30s (N=2267). Indicators included in LCA were 12-month prevalences of symptoms of wheeze, rhinoconjunctivitis, and eczema. Latent classes were further characterised regarding important traits such as skin prick tests. Logistic regression models were used to investigate associations with environmental determinants such as smoking and occupational exposures.

RESULTS

Six latent classes were identified: an asymptomatic one as well as three with single and two with co-occurring symptoms. All trajectories essentially established between baseline assessment at around 10 years and the first follow-up at around 17 years. Probabilities for symptoms increased from childhood to adolescence, especially for wheeze-related latent classes, while they remained constant in adulthood. Wheeze-related latent classes were also positively associated with exposures during adolescence (e.g. active smoking).

CONCLUSION

Distinct trajectories of asthma and allergy symptoms establish from childhood through adolescence and stabilize during early adulthood. This pattern was most notable in wheeze-related latent classes which also showed the strongest positive associations with environmental exposures in adolescence/young adulthood. Therefore, not only childhood but also adolescence is relevant for disease development and offers considerable potential for prevention and health promotion.

Occupational chronic obstructive pulmonary disorder: prevalence and prevention

INTRODUCTION

Occupational chronic obstructive pulmonary disorder, i.e. work-related asthma (WRA) and occupational chronic obstructive pulmonary disease (COPD), are the most common occupational lung diseases in the last decades worldwide. As in the case of the other occupational disorders, these diseases may be prevented.

AREAS COVERED

WRA is a heterogeneous entity that includes three subtypes, immunologic occupational asthma (OA), irritant-induced asthma (IIA), and work-exacerbated asthma (WEA), depending on the role of occupational exposures as a causing or aggravating factor of the disease. In addition, there is consistent evidence that a substantial proportion of COPD cases can be explained by exposure to noxious particles and gases other than tobacco smoke, such as workplace dusts, gases, fumes, and vapors. The articles cited in this paper were searched by keywords in several databases in the period up to May-July 2021.

EXPERT OPINION

The development of occupational chronic obstructive disorder is a matter of prevention. WRA and occupational COPD contribute significantly to the overall burden of asthma and COPD. Activities and measures targeted to elimination or reduction of harmful workplace exposures, as well as to early detection and early intervention in the course of the lung damage, can significantly reduce the burden caused by these diseases.

Assessment of obstructive and restrictive patterns of lung function among the workers of brick kilns

This article aims to measure the obstructive and restrictive patterns of lung function of 506 consented workers aged between 18 and 60 years and having at least 1 year of work experience in brick kilns. A questionnaire was completed by workers and also lung functions were measured using a spirometer. It was observed that 81% of workers had abnormal lung function, with 33% obstructive and 67% restrictive impairments. Further severe obstructive impairment was seen in 56% of workers, 41% having moderate obstructive impairment and only 3% with mild obstructive impairment. Forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1) were significantly reduced (p < 0.05) for both restrictive and obstructive impairments while the FEV1/FVC ratio was non-significant for unhealthy workers with restrictive impairments as compared to obstructive impairments. The pulmonary abnormalities of workers were linked to increased occupational exposure to dust and smoke of brick kilns.

Occupational lung disease: A narrative review of lung conditions from the workplace

Occupational lung diseases are lung conditions caused or made worse by materials when a person is exposed to a workplace. The diagnosis of an occupational disease is important for workers' decision to continue work and for their eligibility under compensation programmes. We revisit the existing lung diseases that are closely associated with the occupation at the workplace namely occupational asthma, silicosis, black lung disease, farmers' lung disease, asbestos-linked disease, and hypersensitivity pneumonitis. Occupational lung diseases contribute toward global health and economic impacts. Prevention and control of occupational lung diseases require a collaborative effort among employers, workers, occupational physicians, pulmonary physicians, industrial hygienists, and members from other disciplines.

Progress in Occupational Asthma

Occupational asthma (OA) represents one of the major public health problems due to its high prevalence, important social and economic burden. The aim of this review is to summarize current data about clinical phenotypes, biomarkers, diagnosis and management of OA, a subtype of work-related asthma. Most studies have identified two phenotypes of OA. One is sensitizer-induced asthma, occuring after a latency period and caused by hypersensitivity to high- or low-molecular weight agents. The other is irritant-induced asthma, which can occur after one or more exposures to high concentrations of irritants without latency period. More than 400 agents causing OA have been identified and its list is growing fast. The best diagnostic approach for OA is a combination of clinical history and objective tests. An important tool is a specific inhalation challenge. Additional tests include assessments of bronchial hyperresponsiveness to methacholine/histamine in patients without airflow limitations, monitoring peak expiratory flow at- and off-work, sputum eosinophil count, exhaled nitric oxide measurement, skin prick tests with occupational allergens and serum specific IgE. Treatment of OA implies avoidance of exposure, pharmacotherapy and education. OA is a heterogeneous disease. Mechanisms of its different phenotypes, their diagnosis, role of new biomarkers and treatment require further investigation.

Occupational Lung Disease

Occupational exposures are a major cause of lung disease and disability worldwide. This article reviews the broad range of types of occupational lung diseases, including airways disease, pneumoconioses, and cancer. Common causes of occupational lung disease are reviewed with specific examples and clinical features. Emphasis on the importance of a detailed history to make an accurate diagnosis of an occupational lung disease is discussed.

Low dose of chlorine exposure exacerbates nasal and pulmonary allergic inflammation in mice

Work-exacerbated asthma (WEA) is defined as preexisting asthma that worsens with exposure to irritants [e.g., chlorine (Cl₂) derivatives] in the workplace. The maximum allowable concentration in the workplace of Cl₂ exposure is 3 mg/ m³ (described in OSHA). We investigated in an experimental asthma model in mice the effects of a single exposure to a sodium hypochlorite dose with this allowed chlorine concentration and a tenfold higher dose. Acute chlorine exposure at 3.3 mg/m³ in the OVA-sensitized group increased eosinophils in the peribronquial infiltrate, cytokine production, nasal mucus production and the number of iNOS positive cells in the distal lung compared to only sensitized mice. The exposure to a higher dose of 33.3 mg/m³ in the OVA-sensitized group resulted in an increase in respiratory system elastance, in the total and differential numbers of inflammatory cells in bronchoalveolar lavage fluid, IL-4, IL-5, and IL-17 in the lungs, eosinophils in peribronquial infiltrate and mucus content in nasal compared to non-exposed and sensitized animals. In this asthma model, chorine exposures at an allowable dose, contributed to the potentiation of Th2 responses. The functional alterations were associated with increased iNOS and ROCK-2 activation in the distal lung.

[Guidelines for methacholine provocation testing]

Bronchial challenge with the direct bronchoconstrictor agent methacholine is commonly used for the diagnosis of asthma. The "Lung Function" thematic group of the French Pulmonology Society (SPLF) elaborated a series of guidelines for the performance and the interpretation of methacholine challenge testing, based on French clinical guideline methodology. Specifically, guidelines are provided with regard to the choice of judgment criteria, the management of deep inspirations, and the role of methacholine bronchial challenge in the care of asthma, exercise-induced asthma, and professional asthma.

Work-Related Asthma

OBJECTIVE

Summarize developed evidence-based diagnostic and treatment guidelines for work-related asthma (WRA).

METHODS

Comprehensive literature reviews conducted with article critiquing and grading. Guidelines developed by a multidisciplinary expert panel and peer-reviewed.

RESULTS

Evidence supports spirometric testing as an essential early test. Serial peak expiratory flow rates measurement is moderately recommended for employees diagnosed with asthma to establish work-relatedness. Bronchial provocation testing is moderately recommended. IgE and skin prick testing for specific high-molecular weight (HMW) antigens are highly recommended. IgG testing for HMW antigens, IgE testing for low-molecular weight antigens, and nitric oxide testing for diagnosis are not recommended. Removal from exposure is associated with the highest probability of improvement, but may not lead to complete recovery.

CONCLUSION

Quality evidence supports these clinical practice recommendations. The guidelines may be useful to providers who diagnose and/or treat WRA.

Patient-physician communication about work-related asthma: what we do and do not know

BACKGROUND

Effective patient-physician communication is the key component of the patient-physician relationship.

OBJECTIVE

To assess the proportion of ever-employed adults with current asthma who talked about asthma associated with work with their physician or other health professional and to identify factors associated with this communication.

METHODS

The 2006 to 2010 Behavioral Risk Factor Surveillance System Asthma Call-Back Survey data from 40 states and the District of Columbia for ever-employed adults (≥18 years old) with current asthma (N = 50,433) were examined. Multivariable logistic regression analyses were conducted to identify factors associated with communication with a health professional about asthma and work.

RESULTS

Among ever-employed adults with current asthma, 9.1% were ever told by a physician that their asthma was related to any job they ever had and 11.7% ever told a physician or other health professional that this was the case. When responses to the 2 questions were combined, the proportion of those who communicated with a health professional about asthma and work was 14.7%. Communication with a health professional about asthma and work was associated with age, race or ethnicity, employment, education, income, insurance, and urgent treatment for worsening asthma.

CONCLUSION

A small proportion of patients with asthma might communicate with a health professional about asthma associated with work. Future studies should examine whether patients with asthma ever discussed with a health professional the possibility that their asthma might be related to work to provide information on the frequency of patient-clinician communication about asthma related to work.

Occupational allergy: respiratory hazards in healthcare workers

PURPOSE OF REVIEW

Allergens are one group of respiratory hazards in the workplace of healthcare workers (HCWs). The purpose of this review is to summarize the recent advances in occupational allergy as well as potential hazardous agents in HCWs.

RECENT FINDINGS

The review covers new developments on the epidemiology, diagnosis and management of occupational allergy in HCWs. This article also provides updated information on the prevalence of work-related respiratory symptoms, as well as on respiratory hazards among healthcare providers.

SUMMARY

It is established that HCWs are at risk of asthma symptoms. The growing use of cleaning products is one of the causes of occupational airway disease in that group. Among healthcare professionals, the prevalence of asthma varies depending on worksite. Recent findings indicate a need for education among HCWs concerning occupational risks. A lack of knowledge of product components as well as about exposure to cleaning/disinfecting agents has been demonstrated. Further studies are necessary to determine the relative role of individual agents versus complex workplace exposures in the development of work-related asthma in HCWs.

Distribution of asthma by occupation: Washington State behavioral risk factor surveillance system data, 2006-2009

Objective

Objective: To estimate the prevalence of asthma in workers by occupation in Washington State. Methods: Data from the 2006–2009 Behavioral Risk Factor Surveillance System (BRFSS) and the BRFSS Asthma Call-Back Survey (ACBS) in Washington State (WA) were analyzed. Using state-added and coded Industry and Occupation questions, we calculated prevalence ratios (PRs) for 19 occupational groups. Results: Of the 41 935 respondents who were currently employed during 2006–2009, the prevalence of current asthma was 8.1% [95% confidence interval (CI) 7.8–8.5%] When compared with the reference group of executive, administration and managerial occupations, three occupational groups had significantly (p < 0.05) higher PRs of current asthma: “Teachers, all levels, and Counselors’ (PR 1.3, 95% CI 1.1–1. 6%); ‘Administrative Support, including Clerical” (PR 1. 5, 95% CI 1.2–1.9%); and “Other Health Services” (PR 1.5, 95% CI 1.2–1.9). Half of the 2511 ACBS respondent workers (55.1%) indicated that they believed exposure at work had caused or worsened their asthma, but only 10.7% had ever spoken with a health care professional about their asthma being work related. Conclusions: Some occupations have a higher prevalence of current asthma than other occupations. The systematic collection of industry and occupation data can help identify worker populations with a high burden of asthma and can be used to target disease prevention efforts as well as to aid clinician recognition and treatment. Workers indicated that work-related asthma exposures are not discussed with their health care provider and this communication gap has implications for asthma management.

Immunological treatments for occupational allergy

Although avoidance of occupational triggers remains the primary step in the management of work-related allergies, immunological treatments (including biological agents and specific immunotherapy) can be regarded as potential therapeutic options for IgE-mediated diseases; for example, many studies with allergen-specific immunotherapy have been carried out on latex allergy, showing overall favorable results, at least with sublingual immunotherapy. On the other hand, only few case reports have suggested the efficacy of immunotherapy in baker's asthma as well as in laboratory animal-induced asthma. The new technologies, including component-resolved diagnosis and recombinant allergens, are expected to improve the quality and efficacy of specific immunotherapy in the future. Also the use of omalizumab may represent a suitable therapeutic choice in very selected cases of occupational allergy, as well as an approach to reduce side effects of venom immunotherapy in subjects with previous severe reactions to the treatment.

Environment and asthma in adults

The present review addresses recent advances and especially challenging aspects regarding the role of environmental risk factors in adult-onset asthma, for which the causes are poorly established. In the first part of the review, we discuss aspects regarding some environmental risk factors for adult-onset asthma: air pollution, occupational exposures with a focus on an emerging risk represented by exposure to cleaning agents (both at home and in the workplace), and lifestyle and nutrition. The second part is focused on perspectives and challenges, regarding relevant topics on which research is needed to improve the understanding of the role of environmental factors in asthma. Aspects of exposure assessment, the complexity of multiple exposures, the interrelationships of the environment with behavioral characteristics and the importance of studying biological markers and gene-environment interactions to identify the role of the environment in asthma are discussed. We conclude that environmental and lifestyle exposures play an important role in asthma or related phenotypes. The changes in lifestyle and the environment in recent decades have modified the specific risk factors in asthma even for well-recognized risks such as occupational exposures. To better understand the role of the environment in asthma, the use of objective (quantitative measurement of exposures) or modern tools (bar code, GPS) and the development of multidisciplinary collaboration would be very promising. A better understanding of the complex interrelationships between socio-economic, nutritional, lifestyle and environmental conditions might help to study their joint and independent roles in asthma.

Diagnosis of occupational asthma: an update

Work-related asthma (WRA) includes patients with sensitizer- and/or irritant-induced asthma in the workplace, as well as patients with preexisting asthma that is worsened by work factors. WRA is underdiagnosed; thus, the diagnosis is critical to prevent disease progression and its potential for morbidity and mortality. The interview is the first diagnostic tool to be used by physicians, and the question, "Does asthma improve away from work?" is of the highest sensitivity. However, history can show numerous false positives, and the relationships between asthma worsening and work should be confirmed by objective methods such as peak expiratory flow (PEF) at and away from work. PEF sensitivity and specificity can be enhanced in combination with nonspecific bronchial hyperresponsiveness to histamine/methacholine (NSBP) before and after 2 weeks at work and a similar period off work. Immunologic testing, especially skin prick test (SPT) or specific IgE, is useful for high molecular weight allergens and some low molecular weight agents. Other immunologic tests, as well as induced sputum, measurement of exhaled nitric oxide, exhaled breath condensate, and specific inhalation challenge (SIC) are methods that contribute to the diagnosis and are typically performed at specialized facilities. A diagnosis of occupational asthma (OA) should no longer be based on a compatible history only but should be confirmed by means of objective testing. SIC is the diagnostic gold standard. When SIC is not available, the combination of PEF measurement, NSBP test , a specific SPT, or specific IgE may be an appropriate alternative in diagnosing OA.

Asthma in the workplace

Occupational asthma (OA) refers to asthma that occurs as a result of workplace inhalation exposures. Most workers exposed to antigens and irritants will not develop OA. Although much more study focused on OA needs to be completed, it can be stated with some surety that identification of IgE-mediated sensitization and bronchial hyperresponsiveness occurs with OA. Also, extreme short-term chemical exposures versus a cumulative effect of chemical exposures will need continued evaluation to determine tolerable levels that do not cause harm. Health care providers often seek guidance from NIOSH, which sponsors ongoing research and training related to workplace exposures.

Research needs in allergy: an EAACI position paper, in collaboration with EFA

In less than half a century, allergy, originally perceived as a rare disease, has become a major public health threat, today affecting the lives of more than 60 million people in Europe, and probably close to one billion worldwide, thereby heavily impacting the budgets of public health systems. More disturbingly, its prevalence and impact are on the rise, a development that has been associated with environmental and lifestyle changes accompanying the continuous process of urbanization and globalization. Therefore, there is an urgent need to prioritize and concert research efforts in the field of allergy, in order to achieve sustainable results on prevention, diagnosis and treatment of this most prevalent chronic disease of the 21st century.The European Academy of Allergy and Clinical Immunology (EAACI) is the leading professional organization in the field of allergy, promoting excellence in clinical care, education, training and basic and translational research, all with the ultimate goal of improving the health of allergic patients. The European Federation of Allergy and Airways Diseases Patients' Associations (EFA) is a non-profit network of allergy, asthma and Chronic Obstructive Pulmonary Disorder (COPD) patients' organizations. In support of their missions, the present EAACI Position Paper, in collaboration with EFA, highlights the most important research needs in the field of allergy to serve as key recommendations for future research funding at the national and European levels.Although allergies may involve almost every organ of the body and an array of diverse external factors act as triggers, there are several common themes that need to be prioritized in research efforts. As in many other chronic diseases, effective prevention, curative treatment and accurate, rapid diagnosis represent major unmet needs. Detailed phenotyping/endotyping stands out as widely required in order to arrange or re-categorize clinical syndromes into more coherent, uniform and treatment-responsive groups. Research efforts to unveil the basic pathophysiologic pathways and mechanisms, thus leading to the comprehension and resolution of the pathophysiologic complexity of allergies will allow for the design of novel patient-oriented diagnostic and treatment protocols. Several allergic diseases require well-controlled epidemiological description and surveillance, using disease registries, pharmacoeconomic evaluation, as well as large biobanks. Additionally, there is a need for extensive studies to bring promising new biotechnological innovations, such as biological agents, vaccines of modified allergen molecules and engineered components for allergy diagnosis, closer to clinical practice. Finally, particular attention should be paid to the difficult-to-manage, precarious and costly severe disease forms and/or exacerbations. Nonetheless, currently arising treatments, mainly in the fields of immunotherapy and biologicals, hold great promise for targeted and causal management of allergic conditions. Active involvement of all stakeholders, including Patient Organizations and policy makers are necessary to achieve the aims emphasized herein.

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.