Joanna Szram

Welding, longitudinal lung function decline and chronic respiratory symptoms: a systematic review of cohort studies

While the acute respiratory risks of welding are well characterised, more chronic effects, including those on lung function, are less clear. We carried out a systematic review of published longitudinal studies of lung function decline in welders. Original cohort studies documenting two or more sequential measurements of lung function were reviewed. Meta-analysis was carried out on studies with suitable data on forced expiratory volume in 1 s (FEV1). Seven studies were included; their quality (measured on the Newcastle–Ottawa scale) was good, although exposure assessment was limited and the studies showed significant heterogeneity. Five had data suitable for meta-analysis; the pooled estimate of the difference in FEV1 decline between welders and nonwelders was -9.0 mL·year−1 (95% CI -22.5–4.5; p=0.193). The pooled estimates of difference in annual FEV1 decline between welders and referents who smoked was -13.7 mL·year−1 (95% CI -33.6–6.3; p=0.179). For welders and referents who did not smoke the estimated difference was -3.8 mL·year−1 (95% CI -20.2–12.6; p=0.650). Symptom prevalence data were mainly narrative; smoking appeared to have the greatest effect on symptom evolution. Collectively, available longitudinal data on decline of lung function in welders and respiratory symptoms suggest a greater effect in those who smoke, supporting a focus on smoking cessation as well as control of fume exposure in this trade. Further prospective studies are required to confirm these findings. Welders who smoke suffer greater decline in lung function http://ow.ly/nUBBb

Medical surveillance for prevention of occupational asthma.

Purpose of reviewBecause 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 findingsHealth 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. SummaryThe 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 in Antibiotic Manufacturing Workers: Case Reports and Systematic Review

Background. The risks of occupational asthma (OA) from antibiotics are uncertain. We report 4 new cases and a systematic review of the literature. Methods. Cases were identified through a specialist clinic, each underwent specific provocation testing (SPT). We subsequently reviewed the published literature. Results. The patients were employed in the manufacture of antibiotics; penicillins were implicated in three cases, in the fourth erythromycin, not previously reported to cause OA. In two, there was evidence of specific IgE sensitisation. At SPT each developed a late asthmatic reaction and increased bronchial hyperresponsiveness. 36 case reports have been previously published, 26 (citing penicillins or cephalosporins). Seven cross-sectional workplace-based surveys found prevalences of 5–8%. Conclusions. OA in antibiotic manufacturers may be more common than is generally recognised. Its pathogenesis remains unclear; immunological tests are of uncertain value and potential cases require confirmation with SPT. Further study of its frequency, mechanisms, and diagnosis is required.

Prevalence of sensitization to 'improver' enzymes in UK supermarket bakers.

Supermarket bakers are exposed not only to flour and alpha‐amylase but also to other ‘improver’ enzymes, the nature of which is usually shrouded by commercial sensitivity. We aimed to determine the prevalence of sensitization to ‘improver’ enzymes in UK supermarket bakers.

Metal worker’s lung: spatial association with Mycobacterium avium

Background Outbreaks of hypersensitivity pneumonitis (HP) are not uncommon in workplaces where metal working fluid (MWF) is used to facilitate metal turning. Inhalation of microbe-contaminated MWF has been assumed to be the cause, but previous investigations have failed to establish a spatial relationship between a contaminated source and an outbreak. Objectives After an outbreak of five cases of HP in a UK factory, we carried out blinded, molecular-based microbiological investigation of MWF samples in order to identify potential links between specific microbial taxa and machines in the outbreak zone. Methods Custom-quantitative PCR assays, microscopy and phylogenetic analyses were performed on blinded MWF samples to quantify microbial burden and identify potential aetiological agents of HP in metal workers. Measurements and main results MWF from machines fed by a central sump, but not those with an isolated supply, was contaminated by mycobacteria. The factory sump and a single linked machine at the centre of the outbreak zone, known to be the workstation of the index cases, had very high levels of detectable organisms. Phylogenetic placement of mycobacterial taxonomic marker genes generated from these samples indicated that the contaminating organisms were closely related to Mycobacterium avium. Conclusions We describe, for the first time, a close spatial relationship between the abundance of a mycobacterium-like organism, most probably M. avium, and a localised outbreak of MWF-associated HP. The further development of sequence-based analytic techniques should assist in the prevention of this important occupational disease.

Occupational Hypersensitivity Pneumonitis: What Is the Evidence, When to Think of It, and What to Do

Hypersensitivity pneumonitis (HP), or extrinsic allergic alveolitis, is a relatively rare condition with a variable natural history (acute, subacute, or chronic) and fairly nonspecific features. Patients present with pulmonary symptoms with or without constitutional disturbance. HP can be caused by >300 different agents, which broadly comprise microbial agents (bacteria, fungus), animal antigens, and chemicals, and exposure to these agents may occur in occupational settings—the focus of this article—or elsewhere. HP, particularly due to occupational exposures, is underdiagnosed due to a lack of awareness of the condition and difficulties in identifying and confirming the diagnosis. Bird fancier’s lung and farmer’s lung have historically been the most common causes of HP. More recently, metalworking fluids used in engineering have emerged as an increasingly common etiological agent for occupational HP and several outbreaks have been reported. Making a diagnosis of occupational HP is crucial both for the individual, so as to remove them from exposure and maximize the chance of a full recovery, and for the employer, so that they can identify other cases and put into place strategies to prevent further cases. There is no single gold standard test used to confirm HP, and a combination of a careful occupational exposure history, clinical history, radiology, and immunology findings can help ascertain a diagnosis. Certain key questions can be useful in eliciting a work-related pattern to symptoms.

P223 Update of the british occupational health foundation (bohrf) evidence-based guidelines on the prevention and management of occupational asthma

Introduction and Objectives Occupational asthma (OA) can be prevented by eliminating or at least minimising exposures to the causal agents at work. However, the rapid development of industrial technologies constantly introduces new potential asthmagens at work and therefore up-to-date knowledge of these changes is pivotal to diagnose and prevent new OA cases. The current evidence-based guidance on the prevention and management of OA was commissioned by the British Occupational Health Foundation (BOHRF) in 2010.1 Our aim was to update these guidelines to help stakeholders reducing the incidence of OA by improved prevention, and the severity of individual cases of disease by earlier identification and better management. Methods We conducted a literature systematic review according to state-of-the-art methods via search of two electronic database (Embase and Medline), using the Ovid interface, from January 2009 to November 2016. Both MeSH and free-text terms were used for combinations of ‘work’ and ‘asthma’. The retrieved references were managed using EndNote software and evaluated blindly by paired reviewers. Critical appraisal of the included articles was performed using the GRADE (Grading of Recommendations, Assessment, Development and Evaluations) scoring system to link evidence-quality evaluations to clinical recommendations. Results From the 2424 references retrieved, 133 met the inclusion criteria (see attached PRISMA flow-chart diagram). Briefly, in terms of occupations, many previously identified were confirmed, such as bakers, and painters, but new ones emerged such as cleaners, suggesting also underlying irritative-mediated causal mechanisms. Not substantial changes in the diagnosis of OA emerged, but new potential frameworks for better management and health surveillance of OA arose. Conclusions Exposure to respiratory hazards at work is still an important cause of asthma worldwide and in the UK, with important costs for both the individual and the society. Updated evidence-based guidelines on the prevention and management of OA are key to guide healthcare workers’ decision-making in their routine clinical practice. Abstract P223 Figure 1 PRISMA flow diagram. Reference British Occupational Health Research Foundation. Occupational Asthma – Identification, Management and Prevention: Evidence Based Review and Guidelines 2010. Available at http://www.bohrf.org.uk/downloads/Occupational AsthmaEvidenceReview-Mar2010.pdf

S3 Work performance and airflow obstruction in a general UK population of older workers

Work disability as a consequence of COPD has been found in a number of patient cohorts and respiratory symptoms were shown to be significantly associated with work limitation in the Lungs at Work study.1 The impact of airflow obstruction on impaired work performance in the general population is unknown. The clinical assessment was designed to examine the relationship between respiratory symptoms and work performance in a general population of older workers in more detail. Volunteers in full time employment at the time of the initial postal questionnaire study (of 51 to 60-year olds through general practice) underwent clinical assessment, including spirometry (n=1773). Results are shown in Abstract S3 table 1. Prevalence of declared doctor-diagnosed COPD was low (1.9% of men and 0.6% of women) compared to that of airflow obstruction on spirometry (post-bronchodilator FEV1<80% predicted and FEV1/FVC ratio<0.7) was higher, similar to previous published estimates. Men and women with airflow obstruction had a significantly higher prevalence of poor self-reported performance at work than individuals with normal spirometry. Subjects of both sexes with abnormal spirometry who also reported high levels of physical activity in their current job were significantly more likely to report poor work performance than individuals without airflow obstruction with similarly high activity levels; this difference was not seen in low activity work (data not shown). Men were significantly more likely than women to predict that they would stop work due to ill-health. In both sexes, participants with abnormal spirometry were significantly more likely to predict ill-health retirement than individuals with normal lung function. This study has demonstrated an association between airflow obstruction and both work performance within a general population of older workers; the level of physical activity required at work had an important effect on this relationship. Future loss from the workforce due to ill-health was also related to lung function. Detection of airflow obstruction could aid retention in employment, provided that suitable interventional strategies are in place to support older workers.Abstract S3 Table 1 Self-reported work performance, physical activity and current work exposures in a general population of adults aged 51–60 in full time employment (n=1773), stratified by sex and airflow obstruction Men (n=1101) n, % Women (n=672) n, % p Value Poor work performance 112 (10.4) 54 (8.2) 0.128 High level of physical activity at work 496 (46.1) 227 (34.6) <0.001 Airflow obstruction* 77 (7.3) 25 (3.9) 0.004 Health will limit ability to work 568 (52.1) 271 (40.7) <0.001 Airflow obstruction* n, % p Value Airflow obstruction* n, % p Value Yes (n=77) No (n=977) Yes (n=25) No (n=617) Poor work performance 13 (16.9) 90 (9.4) 0.035 5 (20.0) 48 (7.9) 0.032 Poor work performance and high level of physical activity at work 11(30.6) 58 (13.4) 0.005 3 (23.1) 15 (7.5) 0.084 Health will limit ability to work 50 (64.9) 495(51.2) 0.020 16 (64.0) 9 (36.0) 0.016* Post-bronchodilator FEV1 <80% predicted and FEV1/FVC ratio <0.7.

Breathlessness and lung function in older working adults is associated with significant work disability

Objectives Breathlessness and airflow limitation increase with age and are likely to result in work disability. Methods A general population survey of adults in their sixth decade was carried out to examine the relationship between breathlessness, work performance, work disability, sickness absence and towards the end of working life. In a cross-sectional postal questionnaire survey of adults aged 51–60 across Kent (n=21 220, 33% response). breathlessness was reported using a modified MRC dyspnoea score, with a number of validated measures used to assess work performance and disability. A subgroup of respondents was assessed with lung function (n=1774). Results Logistic regression showed that increased breathlessness was significantly associated with risk of poor work performance in both sexes. When analysis was adjusted for demographic, psychological and occupational factors, the relationship between breathlessness and work performance remained. Spirometry showed that men with poor work performance had a statistically significant lower mean FEV1 than those with good performance (mean (SD) 3.12L (0.75) vs 3.35L (0.62). Using spirometry data, we found that 8.9% of men and 4.3% of women had lung function that was consistent with a diagnosis of COPD; disease prevalence was markedly higher than that of reported disease (1.9% men and 0.6% women). Conclusions In a large study we found a strong relationship between breathlessness and impaired work performance in older adults, likely to be due in most part to respiratory disease, the majority of it undiagnosed, as confirmed with spirometry. From a wider perspective, it seems likely that the planned increases in pension age will lead to a more disabled UK working population.

S157 Prevalence of asthma related to employment in the UK

It is widely held that 10–15% of adult asthma is causally related to occupation. It is likely that this fraction varies importantly depending on historical and international variations in employment. Further uncertainties arise from misclassification in the diagnosis of asthma and in exposure assessment, particularly if based on self-report. We carried out a postal survey of adults listed as asthmatic through general practices across the UK. Cases, who were defined as those who had experienced onset of asthma or worsening of pre-existing childhood asthma within 2 years of starting a new job, were compared to controls who declared an equivalent onset or deterioration more than 2 years from the start of a job. Of 8535 individuals targeted, 3115 (37%) returned a completed questionnaire. Almost 40% of these (n=1198) experienced a deterioration of pre-existing childhood asthma or onset of adult asthma whilst working; 441 were cases and 757 controls. A priori analysis of risk was performed using an asthma-specific JEM, the ECRHS asthma ‘high risk occupations’ and data from the UK SWORD surveillance scheme. Odds ratios (adjusted for sex, smoking and era of onset and stratified by onset type)—displayed in Abstract S157 Table 1—did not suggest an increased risk of asthma within 2 years of starting a high-risk job. A posteriori analysis of all occupations demonstrated an increased risk of asthma within 2 years of starting a new job in sales and elementary occupations. The calculated population attributable risk (PAR) for these occupations was 15.9% and was higher in women than men. The results from this study suggest that a priori assessment of risk does not identify occupation as a significant cause of asthma in this contemporary adult workforce in the UK. Jobs which do appear to increase risk of new asthma are not those typically associated with an excess risk of the disease. These findings highlight the disparity between epidemiological and clinical assessments of asthma related to occupation, and the need to consider novel occupations as a cause of asthma.Abstract S157 Table 1 Summary of results using a priori risk estimates Exposure definition No of cases in high-risk job No of controls in high-risk job Odds Ratio adjusted 95% Confidence Interval p value JEM All 81 172 0.76 0.55–1.04 0.08 Adult onset 59 145 0.82 0.57–1.18 0.29 Childhood worsening 22 27 0.62 0.31–1.22 0.17 ECRHS All 109 215 0.90 0.68–1.19 0.46 Adult onset 80 181 0.98 0.71–1.35 0.90 Childhood worsening 29 34 0.70 0.38–1.29 0.25 SWORD All 9 31 0.49 0.23–1.04 0.06 Adult onset 6 28 0.44 0.18–1.08 0.07 Childhood worsening 3 3 0.85 0.16–4.41 0.84