Medical surveillance for prevention of occupational asthma

Implementation of a Work-Related Asthma Screening Questionnaire in Clinical Settings: Multimethods Study

Background

A work-related asthma (WRA) screening questionnaire is currently being validated for implementation in clinical settings. To minimize barriers to integrating tools into clinical practice, a discussion of strategies for the implementation of the questionnaire has begun.

Objective

This study aimed to understand the benefits, feasibility, barriers, and limitations of implementing the Work-related Asthma Screening Questionnaire–Long version (WRASQ[L]) and asthma e-tools in clinical settings and propose dissemination and implementation strategies for the WRASQ(L).

Methods

This study was conducted in Kingston, Ontario, Canada, from September 2019 to August 2021. A workshop and 2 questionnaires were used to understand the benefits of and barriers to implementing the questionnaire in clinical settings. An expert advisory committee was established to develop the implementation and dissemination strategies. Workshops were semistructured and used thematic qualitative analysis to identify themes that provided an understanding of the benefits and limitations of and barriers to using the WRASQ(L), and e-tools in general, in clinical settings. Workshop participants included patients and health care providers, including physicians, nurses, and asthma educators, who were implementation specialists and expert electronic medical record users. A questionnaire focusing on providers’ knowledge and awareness of WRA and another focusing on WRASQ(L) feedback was administered at the workshops. Advisory committee members from relevant stakeholders met 3 times to strategize implementation opportunities.

Results

A total of 6 themes were identified in the workshop: involving and addressing patient needs, novel data collection, knowledge translation, time considerations, functional and practical barriers, and human limitations. Questionnaire responses yielded positive feedback on the utility of the WRASQ(L) in clinical settings. All participants agreed that it is an easy way of collecting information on occupational and exposure history and could prompt a discussion between the health care provider and patient on how the workplace and exposures could affect one’s asthma, increase awareness of WRA in patients and providers, and increase awareness of exposures in the workplace. Implementation and dissemination strategies were generated with input from the advisory committee.

Conclusions

Stakeholders and workshop participants consider the WRASQ(L) to be a useful tool that satisfies many provider needs in their clinical settings. Once validated, dissemination strategies will include developing educational materials that include the WRASQ(L), linking the questionnaire to stakeholder websites or e-toolkits, translation into other languages, leveraging health care and research networks, conference presentations, and peer-reviewed publications. Implementation strategies will include integration into electronic medical records; designing multifaceted interventions; and targeting nontraditional settings such as workplaces, pharmacies, and research settings. The WRASQ(L) addresses many benefits of and barriers to implementation, as identified in the workshop themes. These themes will guide future implementation and dissemination strategies, noting that human limitations identified in providers and patients will need to be overcome for successful implementation.

Improving detection of work-related asthma: a review of gaps in awareness, reporting and knowledge translation

Background

Work-related asthma (WRA) accounts for up to 25% of all adults with asthma. Early diagnosis is key for optimal management as delays in diagnosis are associated with worse outcomes. However, WRA is significantly underreported and the median time to diagnosis is 4 years. The objective of this review is to identify the gaps in awareness and reporting of WRA and identify gaps in current knowledge translation strategies for chronic disease in general, and asthma specifically. This will identify reasons for delays in WRA diagnosis, as well inform suggestions to improve knowledge translation strategies for dissemination and implementation of WRA prevention and management guidelines.

Methods

Non-systematic literature reviews were conducted on PubMed with a focus on work-related asthma screening and diagnosis, and knowledge translation or translational medicine research in asthma and chronic disease. In total, 3571 titles and abstracts were reviewed with no restriction on date published. Of those, 207 were relevant and fully read. Another 37 articles were included and reviewed after citation reviews of articles from the initial search and from suggestions from editors. In total, 63 articles were included in the final review.

Results

Patients, employers, and healthcare professionals lack awareness and under-report WRA which contribute to the delayed diagnosis of WRA, primarily through lack of education, stigma associated with WRA, and lack of awareness and screening in primary care. Knowledge translation strategies for asthma research typically involve the creation of guidelines for diagnosis of the disease, asthma care plans and tools for education and management. While there are some prevention programs in place for certain industries, gaps in knowledge translation strategies including lack of screening tools currently available for WRA, poor education of employers and physicians in identifying WRA, and education of patients is often done post-diagnosis and focuses on management rather than prevention or screening.

Conclusion

Future knowledge translation strategies should focus on educating employees and employers well before potential exposure to agents associated with WRA and screening for WRA in primary care to enable health care providers to recognize and diagnose WRA.

Impact of Identification of Clinical Phenotypes in Occupational Asthma

Phenotypic differences and similarities in the spectrum of occupational asthma (OA) subtypes reflect the underlying mechanisms of the diverse forms of the disease, and these phenotypes provide information as to diagnostic steps and approaches to management. In large part, the phenotype reflects the existence of immunologic mechanisms and the presence or absence of a specific IgE-antibody response to a work sensitizer. However, further differences occur between OA from high- and low-molecular-weight sensitizers (chemical sensitizers), which potentially might be relevant for nonoccupational asthma. Chemical sensitizers cause a specific response that is more likely to be a late asthmatic response and specific IgE can be identified only in a minority. Irritant-induced asthma is most easily recognized when it occurs with 1 or more high-level respiratory irritant exposure(s) but is also possible with chronic low-level exposures as in cleaners, farmers, and woodworkers, as suggested from epidemiologic studies. OA chronic obstructive pulmonary disease overlap is more common in older patients and with OA from low-molecular-weight sensitizers. Removal from exposure to the causative agent is currently advised for those with OA from sensitization: further studies with omalizumab and other biologic agents are needed to determine whether these might allow return to the same exposure.

Current and new challenges in occupational lung diseases

Occupational lung diseases are an important public health issue and are avoidable through preventive interventions in the workplace. Up-to-date knowledge about changes in exposure to occupational hazards as a result of technological and industrial developments is essential to the design and implementation of efficient and effective workplace preventive measures. New occupational agents with unknown respiratory health effects are constantly introduced to the market and require periodic health surveillance among exposed workers to detect early signs of adverse respiratory effects. In addition, the ageing workforce, many of whom have pre-existing respiratory conditions, poses new challenges in terms of the diagnosis and management of occupational lung diseases. Primary preventive interventions aimed to reduce exposure levels in the workplace remain pivotal for elimination of the occupational lung disease burden. To achieve this goal there is still a clear need for setting standard occupational exposure limits based on transparent evidence-based methodology, in particular for carcinogens and sensitising agents that expose large working populations to risk. The present overview, focused on the occupational lung disease burden in Europe, proposes directions for all parties involved in the prevention of occupational lung disease, from researchers and occupational and respiratory health professionals to workers and employers.

Review of Diagnostic Challenges in Occupational Asthma

PURPOSE OF REVIEW

Occupational asthma (OA) is one of the most frequent occupational diseases and its diagnosis is often difficult. This review summarizes its current diagnostic challenges.

RECENT FINDINGS

OA is associated with significant health and socio-economic burden. It is underdiagnosed and physicians need to adopt a stepwise approach to confirm the diagnosis. Although early removal from exposure to the offending agent is associated with a better prognosis, physicians should try to confirm the diagnosis of work-related asthma before taking a worker off work. A proper occupational and medical history is very important but is not enough to make the diagnosis of OA. Objective evidence of work-related asthma is required and this represents a serious challenge to most physicians. Measurement of non-specific bronchial responsiveness (NSBR) and spirometry may confirm the diagnosis of asthma but do not confirm the diagnosis of OA. Serial monitoring of peak expiratory flows (PEF), NSBR, and airway inflammation at and off work may confirm the diagnosis of OA but are often difficult to perform. Confirming sensitization by skin prick tests or specific IgE may help to support the diagnosis of OA. Specific inhalation challenges (SIC) in the lab or at work are considered the reference standard but are of limited access. Medical surveillance programs along with primary prevention (reducing exposure) may help to reduce the burden of OA, but the ideal program has yet to be defined. The diagnostic workup of OA remains a challenge and needs a rigorous stepwise evaluation.

Medical surveillance for occupational asthma-how are cases detected?

Background

In Finland, medical surveillance, including spirometry, is periodically performed for workers who are exposed to agents capable of causing occupational asthma (OA). Although it has been shown that surveillance can detect OA at an early stage, few studies have assessed its benefits or the role of surveillance spirometry.

Aims

To assess the role of surveillance and spirometry in detecting OA and to evaluate the quality of spirometry.

Methods

We retrospectively reviewed the medical files of patients in health surveillance programmes who were diagnosed with sensitizer-induced OA at the Finnish Institute of Occupational Health in 2012‒14. We collected information on work exposure, respiratory symptoms, healthcare visits that initiated the diagnostic process, first spirometry and other diagnostic tests.

Results

Sixty files were reviewed. Medical surveillance detected 11 cases (18%) and 49 cases (82%) were detected at doctors' appointments that were not related to surveillance. The median delay from the onset of asthma symptoms to diagnosis was 2.2 years. Delay did not differ between these groups. No cases were detected on the basis of abnormal spirometry without respiratory symptoms. However, five patients (8%) initially reported solely work-related rhinitis symptoms. Spirometry was normal in half of the cases and quality criteria were fulfilled in 86% of the tests.

Conclusions

Fewer than one in five OA cases were detected through medical surveillance. Investigations were initiated by respiratory symptoms. No asymptomatic worker was referred because of abnormal spirometry. Our results highlight the importance of work-related nasal symptoms in detecting OA.

New developments in work-related asthma

INTRODUCTION

Work-related asthma includes two subtypes: occupational asthma or asthma caused by specific agents (sensitizers or irritants) in the workplace, and work-exacerbated asthma or pre-existing asthma worsened by workplace exposures. Areas covered: This review provides an update on the definitions and the clinical features of the different work-related asthma subtypes as well as new insights into their etiology and the pathophysiological mechanisms involved. The diagnosis of work-related asthma should be made on objective basis using a constellation of clinical, physiologic and allergologic tests. Specific inhalation challenge with the suspected occupational agent(s) remains as the reference standard for diagnosis. A literature search was performed using the following terms: work-related asthma, occupational asthma, work-exacerbated asthma, irritant-induced asthma and etiological agents. Expert commentary: Studies focusing on the biological effects and mechanisms of environmental exposures in the development of sensitizer-induced or irritant-induced asthma in various workplace settings are of greatest interest. An integrative approach that combines clinical parameters with component-resolved diagnosis as well as inflammatory biomarkers appears to be very promising. Occupational allergy provides a good opportunity to understand the complex relationships between exposure to allergens in the workplace, interaction with genes and the co-exposures to other factors in the working environment.

Environmental factors associated with baseline and serial changes in fractional exhaled nitric oxide (FeNO) in spice mill workers

BACKGROUND

This study evaluated the determinants of high fractional exhaled nitric oxide (FeNO; >50 ppb) and serial changes in FeNO over a 24-hour period in spice mill workers at risk of work-related allergic respiratory disease and asthma.

METHODS

A cross-sectional study of 150 workers used European Community Respiratory Health Survey (ECRHS) questionnaires, Phadiatop, serum-specific IgE (garlic, chilli pepper, wheat; Phadia, ImmunoCAP), spirometry and FeNO. A hand-held portable nitric oxide sampling device (NIOX MINO, Aerocrine AB) measured FeNO before and after the 8-hour shift and after 24 hours from baseline.

RESULTS

The mean age of workers was 33 years; 71% were male, 46% current smokers and 45% atopic. Among workers with garlic sensitisation, 13% were monosensitised and 6% were co-sensitised to chilli pepper. Baseline preshift FeNO geometric mean (GM=14.9 ppb) was similar to the mean change across shift (GM=15.4 ppb) and across the 24-hour period (GM=15.8 ppb). In multivariate linear models, smoking (β=-0.507) and atopy (β=0.433) were strongly associated with FeNO. High FeNO (>50 ppb) was significantly associated with asthma-like symptoms due to spice dust (OR=5.38, CI 1.01 to 28.95). Sensitisation to chilli pepper was more strongly correlated with FeNO (r=0.32) and FeNO>50 ppb (OR=17.04, p=0.005) than garlic. FeNO increase (>12%) across 24 hours demonstrated a strong association with elevated exposures to spice dust particulate (OR=3.77, CI 1.01 to 14.24).

CONCLUSIONS

This study suggests that chilli pepper sensitisation is associated with high FeNO (>50 ppb), more strongly compared with garlic, despite the low prevalence of sensitisation to chilli. Elevated inhalant spice dust particulate is associated with a delayed elevation of FeNO across the 24-hour period.

Respiratory disability and impairment: what is new?

PURPOSE OF REVIEW

This review summarizes recent advances concerning respiratory impairment and disability.

RECENT FINDINGS

The traditional impairment assessment approach, depending heavily on clinical pulmonary function testing to estimate the match between the patient's sustainable oxygen consumption and the workplace requirements, continues to be widely used. Recent work indicates the need to reassess underlying concepts for several reasons: The relationship between basic pulmonary function tests and sustainable oxygen consumption varies among patients and conditions. Studies of the respiratory demands of modern workplaces need to be updated. The concepts are less easily applied to asthma than other disorders. Research studies present differing definitions of 'disability', and therefore the methods of relating impairment (function loss) and disability require reassessment. Recent advances provide improved understanding of the large societal and personal impacts of respiratory impairment and disability.

SUMMARY

Clinicians, policymakers, and researchers should carefully consider how well the current highly specified impairment rating systems can be improved for accuracy and relevance to current home and work activities. In addition to measuring 'impairment', clinicians should consider factors affecting how impairments lead to disability.

Clinical aspects of work-related asthma: past achievements, persistent challenges, and emerging triggers

OBJECTIVE

The aim of this article was to address common clinical questions pertaining to work-related asthma (WRA).

METHODS

This review is based on a presentation on WRA at the American College of Chest Physicians Course on Clinical Aspects of Occupational and Environmental Lung Disease, held in Toronto in 2013, and supplemented by a PubMed search of publications to 2013.

RESULTS

Seven clinical questions are addressed in relation to definitions, causes, diagnosis, management and emerging triggers, and challenges of WRA.

CONCLUSIONS

Although knowledge is expanding in this area, there remain challenges and uncertainties, particularly in the prevention of WRA.

Work-related allergies to storage mites in Parma (Italy) ham workers

OBJECTIVES

To investigate the role of storage mites in the development of allergic diseases among ham production workers, and to search for early alterations in lung function tests and early inflammation markers in exhaled air. Respiratory allergies due to storage mites have been reported in people with various occupations but, although such mites are unavoidable when curing ham, there are no published data concerning ham production workers.

SETTING

Secondary care.

DESIGN

Experimental cross-sectional study.

PARTICIPANTS

220 participants (110 ham production workers and 110 controls) were recruited.

PRIMARY AND SECONDARY OUTCOME MEASURES

Workers answered a medical questionnaire, and underwent spirometry and fraction of exhaled nitric oxide at 50 mL/s (FeNO₅₀) measurements. Those with allergic symptoms also underwent skin prick tests to determine their sensitisation to airborne allergens. A methacholine test was performed in symptomatic participants when spirometry was normal to assess airways hyper-responsiveness.

RESULTS

Symptomatic storage mite sensitisation was observed in 16 workers (14.5%) (rhinoconjunctivitis in 15 (63%) and asthma in (4%)) and 2 controls (1.8%; p=0.001). Higher FeNO₅₀ values in exposed symptomatic workers compared with healthy control participants (34.65±7.49 vs 13.29±4.29 ppb; p<0.001) suggested bronchial and nasal involvement, although their lung function parameters were normal. Regardless of exposure, a FeNO₅₀ value of 22.5 ppb seems to be 100% sensitive and 99.4% specific in distinguishing allergic and non-allergic participants. Multivariate analysis of FeNO₅₀ values in the symptomatic participants showed that they were positively influenced by IgE-mediated allergy (p=0.001) and reported symptom severity (p=0.041), and negatively by smoking status (p=0.049).

CONCLUSIONS

Ham processing workers, as well as workers involved in any meat processing work that includes curing, should be informed about the occupational risk of sensitisation to mites.