The Occupational Burden of Nonmalignant Respiratory Diseases. An Official American Thoracic Society and European Respiratory Society Statement

Abstract

Rationale: Workplace inhalational hazards remain common worldwide, even though they are ameliorable. Previous American Thoracic Society documents have assessed the contribution of workplace exposures to asthma and chronic obstructive pulmonary disease on a population level, but not to other chronic respiratory diseases. The goal of this document is to report an in-depth literature review and data synthesis of the occupational contribution to the burden of the major nonmalignant respiratory diseases, including airway diseases; interstitial fibrosis; hypersensitivity pneumonitis; other noninfectious granulomatous lung diseases, including sarcoidosis; and selected respiratory infections. Methods: Relevant literature was identified for each respiratory condition. The occupational population attributable fraction (PAF) was estimated for those conditions for which there were sufficient population-based studies to allow pooled estimates. For the other conditions, the occupational burden of disease was estimated on the basis of attribution in case series, incidence rate ratios, or attributable fraction within an exposed group. Results: Workplace exposures contribute substantially to the burden of multiple chronic respiratory diseases, including asthma (PAF, 16%); chronic obstructive pulmonary disease (PAF, 14%); chronic bronchitis (PAF, 13%); idiopathic pulmonary fibrosis (PAF, 26%); hypersensitivity pneumonitis (occupational burden, 19%); other granulomatous diseases, including sarcoidosis (occupational burden, 30%); pulmonary alveolar proteinosis (occupational burden, 29%); tuberculosis (occupational burden, 2.3% in silica-exposed workers and 1% in healthcare workers); and community-acquired pneumonia in working-age adults (PAF, 10%). Conclusions: Workplace exposures contribute to the burden of disease across a range of nonmalignant lung conditions in adults (in addition to the 100% burden for the classic occupational pneumoconioses). This burden has important clinical, research, and policy implications. There is a pressing need to improve clinical recognition and public health awareness of the contribution of occupational factors across a range of nonmalignant respiratory diseases.

Keywords: interstitial fibrosis; nonmalignant respiratory diseases; occupational; pneumonitis; respiratory infections; sarcoidosis; workplace.

Figure 1.

Asthma: population attributable fraction (PAF). Forest plot of studies relevant to estimating the occupational contribution to asthma. The estimated PAF, confidence interval (CI), and weighted contribution for each study, as well as the calculated pooled estimate (red dashed line) and 95% CI, are shown. For asthma, the pooled PAF for work exposures is 16% (95% CI, 10–22%). ES = effect size.

Figure 2.

Chronic obstructive pulmonary disease (COPD): population attributable fraction (PAF). Forest plot of studies relevant to estimating the occupational contribution to COPD. The estimated PAF, confidence interval (CI), and weighted contribution for each study are shown, as well as the calculated pooled estimate (red dashed line) and 95% CI. For COPD, the pooled PAF for work exposures is 14% (95% CI, 10–18%). ES = effect size.

Figure 3.

Chronic bronchitis: population attributable fraction (PAF). Forest plot of studies relevant to estimating the occupational contribution to chronic bronchitis. The estimated PAF, confidence interval (CI), and weighted contribution for each study are shown, as well as the calculated pooled estimate (red dashed line) and 95% CI. For chronic bronchitis, the pooled PAF for work exposures is 13% (95% CI, 6–21%). ES = effect size.

Figure 4.

Idiopathic pulmonary fibrosis (IPF): population attributable fraction (PAF) from vapors, gas, dust, or fumes (VGDF). Forest plot of studies relevant to estimating the occupational contribution to IPF of VGDF (combined categories of exposure considered in the studies included). The estimated PAF, confidence interval (CI), and weighted contribution for each study are shown, as well as the calculated pooled estimate (red dashed line) and 95% CI. For IPF, the pooled PAF for VGDF is 26% (95% CI, 10–41%). ES = effect size.

Figure 5.

Hypersensitivity pneumonitis (HP): occupational burden. Forest plot of studies relevant to estimating the contribution of work exposures to HP. The occupational prevalence of HP, confidence interval (CI), and weighted contribution for each study are shown, as well as the calculated pooled estimate (red dashed line) and 95% CI. The pooled proportion of occupational HP among all HP cases is 19% (95% CI, 12–28%). ES = effect size.

Figure 6.

Summary of the occupational burden of nonmalignant respiratory disease, by condition: the estimated contribution of work exposures to the burden of disease across multiple nonmalignant respiratory conditions. The occupational population attributable fractions for asthma (16%), chronic obstructive pulmonary disease (COPD) (14%), chronic bronchitis (CB) (13%), idiopathic pulmonary fibrosis (IPF) (26%), and community-acquired pneumonia (CAP) (10%) are shown. The occupational burden estimates for pulmonary alveolar proteinosis (PAP) (29%), hypersensitivity pneumonitis (HP) (19%), sarcoid (30%), silica-associated tuberculosis (TB) (2.3%), and healthcare worker–associated TB (HC) (1.0%) are based on mixed methods.