Characterization of chronic obstructive pulmonary disease in dairy farmers.

BACKGROUND: Although farming is often considered a risk factor for COPD, data regarding the burden and characteristics of COPD in dairy farmers are sparse and conflicting. OBJECTIVES: To characterize COPD in dairy farmers. METHODS: 4788 subjects entered two parallel COPD screening programs, one in agricultural workers and one in general practice from 2011 to 2015. Subjects with COPD were invited to participate in the characterization phase of the study. Those who accepted were included in two subgroups: dairy farmers with COPD (DF-COPD) (n = 101) and non-farmers with COPD (NF-COPD) (n = 85). Patients with COPD were frequency-matched with subjects with normal spirometry for age, sex and tobacco smoking (pack-years and status) (DF-controls n = 98, NF-controls n = 89). All subjects from these four groups underwent lung function and exercise testing, questionnaires and blood analysis. RESULTS: The frequency of COPD in dairy farmers was 8.0% using the GOLD criterion and 6.2% using the lower limit of normal criterion and was similar in non-farming subjects (7.3% and 5.2%, respectively) although dairy farmers had lower tobacco consumption (screening phase). DF-COPD had better pulmonary function, exercise capacity and quality of life, fewer symptoms and comorbidities than NF-COPD, and higher levels of some Th2 biomarkers (MCP-2, periostin) (characterization phase). In farmers, COPD was not related to occupational exposure factors, supporting the role of host factors. CONCLUSION: COPD secondary to organic dust exposure (dairy farming) appears less severe and associated with fewer comorbidities than COPD secondary to tobacco smoking.

In Patients with Mild-to-Moderate COPD, Tobacco Smoking, and Not COPD, Is Associated with a Higher Risk of Cardiovascular Comorbidity.

Background: Comorbidities including cardiovascular diseases are very common in chronic obstructive pulmonary disease (COPD) secondary to tobacco smoking and contribute to the overall severity of the disease. In non-smoking COPD, which accounts for about 25% of COPD cases worldwide, current knowledge on the frequency and determinants of comorbidities remains scarce. The aims of the current study were to assess the frequency of major comorbidities and to evaluate their determinants in a group of non-selected patients with mild-to-moderate COPD who were exposed to organic dust (dairy farmers), to tobacco smoking, or to both, and in controls without COPD who were exposed to organic dust (dairy farmers), or to tobacco smoking, or to both, or who were without exposure. Patients and Methods: A total of 4665 subjects (2323 dairy farmers and 2342 non-farmers) including 355 patients with COPD and 4310 controls with normal spirometry were recruited through a large COPD screening program. Self-reported physician-diagnosed diseases with plausible links to COPD were recorded in this cross-sectional study. Results: Whatever the exposure, cardiovascular comorbidities were not more frequent in patients with COPD than their counterparts without airflow limitation. A higher risk of major cardiovascular comorbidities was associated with tobacco smoking and a lower risk was associated with exposure to organic dusts. Conclusion: Tobacco smoking (but not COPD) is associated with higher frequency of cardiovascular comorbidities. By contrast, being a dairy farmer exposed to organic dusts is associated with a lower frequency of the same comorbidities. This reinforces the crucial need for controlling established cardiovascular risk factors even in patients with mild-to-moderate COPD.