BACKGROUND: The impact of work-related asthma (WRA) on quality of life (QoL) and work productivity remains largely neglected/uncertain despite its high prevalence. OBJECTIVE: To investigate the association of WRA with QoL and work productivity as compared with subjects with non-WRA and those without asthma and rhinitis. METHODS: A cross-sectional survey was carried out among workers during their periodic occupational health visit in Belgium. The Mini Asthma Quality of Life Questionnaire, the 8-item Medical Outcome Study Short Form instrument, and the Work Productivity and Activity Impairment-General Health questionnaire were administered. Survey participants were divided into 3 groups: (1) WRA (current asthma with ≥2 respiratory symptoms at work; n = 89); (2) non-WRA (current asthma without work-related respiratory symptoms; n = 119); and (3) the reference group (no asthma and no lower respiratory, nasal, or eye symptoms; n = 815). Associations of QoL and work productivity with WRA were evaluated by multivariable regression analyses. RESULTS: WRA and having poor asthma control were significantly associated with lower global Mini Asthma Quality of Life Questionnaire scores compared with non-WRA. Asthmatic subjects had significantly lower physical and mental health component scores of the 8-item Medical Outcome Study Short Form instrument and overall work productivity compared with the reference group, with greater impairment in workers with WRA than in those without WRA. Moreover, workers with WRA had higher percentages of doctor visits and income reduction because of respiratory symptoms than those with non-WRA. Work-related rhinitis and depression were associated with reduced QoL, independent of the effect of WRA. CONCLUSIONS: WRA should be managed comprehensively to reduce the worsening of QoL and work productivity of those affected.

In industrialized and developing countries, occupational asthma (OA) is one of the most common chronic occupational respiratory diseases.1,2 Worldwide, especially in developing countries, OA remains under-recognized and poorly diagnosed.2 | | Based on available resources, diagnostic tests are used in a stepwise approach starting with a detailed medical and occupational history; assessment of nonspecific bronchial hyperresponsiveness (NSBHR); and immunological sensitization with skin-prick tests (SPT) or specific immunoglobulin E to workplace agent when available.3 The second step includes serial assessments of NSBHR and peak expiratory flow at work and off-work, or specific inhalation challenge (SIC). As the reference test for diagnosing OA, SIC is only available in a few centers around the world. Therefore, Suarthana and colleagues developed non-SIC-based diagnostic models for OA using Quebec data of 160 symptomatic subjects who completed an SIC procedure (ie, development set).4 These subjects were exposed to high-molecular-weight (HMW) protein agents such as flour, laboratory animal allergens, and latex. OA was defined as a positive SIC, namely a sustained fall in forced expiratory volume in one second (FEV1) >20% from baseline value after exposure to the suspected occupational agent.5

BACKGROUND: Bronchiolitis obliterans, an irreversible lung disease, was first associated with inhalation of butter flavorings (diacetyl) in workers at a microwave popcorn company. Excess rates of lung-function abnormalities were related to cumulative diacetyl exposure. Because information on potential excess mortality would support development of permissible exposure limits for diacetyl, we investigated respiratory-associated mortality during 2000-2011 among current and former workers at this company who had exposure to flavorings and participated in cross-sectional surveys conducted between 2000-2003. METHODS: We ascertained workers' vital status through a Social Security Administration search. Causes of death were abstracted from death certificates. Because bronchiolitis obliterans is not coded in the International Classification of Disease 10 revision (ICD-10), we identified respiratory mortality decedents with ICD-10 codes J40-J44 which encompass bronchitis (J40), simple and mucopurulent chronic bronchitis (J41), unspecified chronic bronchitis (J42), emphysema (J43), and other chronic obstructive pulmonary disease (COPD) (J44). We calculated expected number of deaths and standardized mortality ratios (SMRs) with 95% confidence intervals (CI) to determine if workers exposed to diacetyl experienced greater respiratory mortality than expected. RESULTS: We identified 15 deaths among 511 workers. Based on U.S. population estimates, 17.39 deaths were expected among these workers (SMR = 0.86; CI:0.48-1.42). Causes of death were available for 14 decedents. Four deaths among production and flavor mixing workers were documented to have a multiple cause of 'other COPD' (J44), while 0.98 'other COPD'-associated deaths were expected (SMR = 4.10; CI:1.12-10.49). Three of the 4 'other COPD'-associated deaths occurred among former workers and workers employed before the company implemented interventions reducing diacetyl exposure in 2001. CONCLUSION: Workers at the microwave popcorn company experienced normal rates of all-cause mortality but higher rates of COPD-associated mortality, especially workers employed before the company reduced diacetyl exposure. The demonstrated excess in COPD-associated mortality suggests continued efforts to lower flavoring exposure are prudent.

BACKGROUND: We evaluated the effectiveness of workplace changes to prevent indium lung disease, using 2002-2010 surveillance data collected by an indium-tin oxide production facility. METHODS: We assessed pulmonary function using lower limits of normal. Blood indium concentration and personal air sampling data were used to estimate exposure. RESULTS: Abnormalities were uncommon at hire. After hire, prevalence of spirometric restriction was 31% (n = 14/45), about fourfold higher than expected. Excessive decline in FEV1 was elevated at 29% (n = 12/41). Half (n = 21/42) had blood indium ≥5 microg/l. More recent hires had fewer abnormalities. There was a suggestion that abnormalities were more common among workers with blood indium ≥5 microg/l, but otherwise an exposure-response relationship was not evident. Peak dust concentrations were obscured by time averaging. CONCLUSIONS: Evolving lung function abnormalities consistent with subclinical indium lung disease appeared common and merit systematic investigation. Traditional measures of exposure and response were not illustrative, suggesting fresh approaches will be needed. Workplace changes seemed to have had a positive though incomplete impact; novel preventive interventions are warranted. (Am. J. Ind. Med. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.)

OBJECTIVE: To evaluate the incidence of post-hire asthma (PHA) among insect-rearing workers, defined as asthma, the symptoms of which appeared after hire at the current workplace. METHODS: We surveyed the health of workers at three insect-rearing facilities and an associated office facility. We calculated the incidence and estimated hazard ratios for PHA. RESULTS: Post-hire asthma incidence in 157 insect-rearing workers was 16.2 per 1000 person-years compared with 9.2 per 1,000 person-years in 70 office workers. Workers with predominant exposure to Lepidoptera had an incidence of 26.9 per 1000 person-years and a hazard ratio of 5.5 (95% confidence interval: 1.6 to 23.9) adjusted for sex, race, and parental asthma. In contrast, the presence of specific immunoglobulin E to Lepidoptera antigens was not associated with PHA. CONCLUSION: Insect-rearing workers had a high incidence of PHA, primarily accounted for by workplace exposure to Lepidoptera.

BACKGROUND: Reports of pulmonary fibrosis, emphysema, and, more recently, pulmonary alveolar proteinosis (PAP) in indium workers suggested that workplace exposure to indium compounds caused several different lung diseases. METHODS: To better understand the pathogenesis and natural history of indium lung disease, a detailed, systematic, multidisciplinary analysis of clinical, histopathological, radiological, and epidemiologic data for all reported cases and workplaces was undertaken. RESULTS: Ten men (median age, 35 years) who produced, used, or reclaimed indium compounds were diagnosed with interstitial lung disease (ILD) 4-13 years after first exposure (n=7) or PAP 1-2 years after first exposure (n=3). Common pulmonary histopathological features in these patients included intraalveolar exudate typical of alveolar proteinosis (n=9), cholesterol clefts and granulomas (n=10), and fibrosis (n=9). Two patients with ILD had pneumothoraces. Lung disease progressed following cessation of exposure in most patients and was fatal in two. Radiographical data revealed that two patients with PAP subsequently developed fibrosis and one also developed emphysematous changes. Epidemiologic investigations demonstrated the potential for exposure to respirable particles and an excess of lung abnormalities among co-workers. CONCLUSIONS: Occupational exposure to indium compounds was associated with PAP, cholesterol ester crystals and granulomas, pulmonary fibrosis, emphysema, and pneumothoraces. The available evidence suggests exposure to indium compounds causes a novel lung disease that may begin with PAP and progress to include fibrosis and emphysema, and, in some cases, premature death. Prospective studies are needed to better define the natural history and prognosis of this emerging lung disease and identify effective prevention strategies.

OBJECTIVE: To assess whether the recent increases in the prevalence of coal workers' pneumoconiosis (CWP) in the USA reflect increased measured exposures over recent decades, and to identify other potential causative factors. METHODS: The observed CWP prevalence was calculated for 12 408 underground coal miner participants in the Coal Workers' Health Surveillance Program for the period 2005-2009, stratified by the Mine Safety and Health Administration (MSHA) geographical districts. The predicted prevalence was estimated using a published exposure-response model from a large epidemiological study among US coal miners using dust exposure, tenure, miner's age and coal rank as predictors. chi(2) Testing was performed to compare the observed versus predicted CWP prevalence. RESULTS: Observed prevalence was significantly higher than predicted prevalence in MSHA districts 4-7 (central Appalachian region) (10.1% vs 4.2%; prevalence ratio (PR) 2.4; p<0.001) and significantly lower than predicted in other regions (1.6% vs 3.6%; PR 0.4; p<0.001). The central Appalachian region had a significantly older workforce with greater mining tenure, a lower proportion of mines with 200 or more employees, and lower seam heights. Significant lower average compliance dust concentrations were reported for this region. CONCLUSION: The observed CWP prevalence substantially exceeded predicted levels in central Appalachia. However, the increased prevalence was not explained by the measured levels of dust exposures. Likely contributing factors include mine size and low seam mining, which may be associated with higher exposure to silica. Further study is needed to characterise the responsible factors for the elevated CWP rates in central Appalachia.

OBJECTIVE: To assess the distribution of illness by industry sector and occupation reflected in early 2009 H1N1 influenza surveillance. METHODS: We analyzed data reported for April to July 2009, for 1361 laboratory-confirmed 2009 H1N1 influenza-infected persons 16 years or older, with work status information from four states. A North American Industry Classification System 2007 code was assigned to each employed person. For a subset, an occupation code was assigned. RESULTS: Of 898 employed individuals, 611 (68.0%) worked in the non-health care sector. The largest proportions worked in public administration, educational services, and accommodation and food services. In Wisconsin health care personnel, 53.6% were paraprofessionals, 33.6% professionals, and 12.7% other workers; 26.9% worked in ambulatory settings, 46.2% in hospitals, and 26.9% in nursing or residential care facilities. CONCLUSIONS: Our findings suggest that industry sectors and occupations should be explored systematically in future influenza surveillance.