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.

Dietary Patterns and Prevalence of Post-bronchodilator Airway Obstruction in Dairy Farmers Exposed to Organic Dusts.

Exposure to organic dusts is an independent causative factor of chronic obstructive pulmonary disease (COPD). Unhealthy dietary patterns have been associated with poor lung function in smokers. This study investigated whether dietary patterns were associated with post-bronchodilator airway obstruction, a hallmark of COPD, in dairy farmers exposed to organic dusts. All subjects were identified by screening programs and patients with airflow obstruction were matched with subjects with normal spirometry. Six groups were compared, defined by their exposures (non-smoking dairy farmers, smokers ≥ 10 pack-years with no occupational exposure, and smoking dairy farmers) and the presence or absence of post-bronchodilator airflow obstruction, resulting in 321 study subjects. The Alternative Healthy Eating Index (AHEI) score was calculated based on an adapted food frequency questionnaire. Mean total AHEI scores were similar in all groups. Comparison between smokers with post-bronchodilator airway obstruction and subjects with post-bronchodilator airway obstruction related to occupational exposure found minimal differences in dietary patterns: dairy farmers had lower scores for the ratio of white to red meat and higher scores for cereal fiber consumption. As in previous studies, smokers with post-bronchodilator airway obstruction exhibited higher lipid intakes and lower carbohydrate intakes than their counterparts with normal spirometry. No evidence of any meaningful difference in dietary patterns was found between subjects with post-bronchodilator airway obstruction detected by screening and healthy controls, either in dairy farmers or in smokers with no occupational exposure.

Is atopy a risk indicator of chronic obstructive pulmonary disease in dairy farmers?

Allergic mechanisms related to environmental and occupational exposure have been suggested to contribute to the development of chronic obstructive pulmonary disease (COPD). OBJECTIVES: To investigate the relationships between atopy markers, persistent airflow limitation (PAL) and occupational exposure in dairy farmers. METHODS: Clinical and biological (total IgE and 21 allergen specific IgE) markers of atopy were assessed in 101 dairy farmers with PAL (DF-PAL), 85 non-farmers with PAL (NF-PAL) (both groups were prospectively included from a screening program performed between 2011 and 2015), and matched controls, i.e. 98 farmers without PAL (DF-controls) and 89 non-farming subjects without PAL (NF-controls). Occupational exposure in farmers was estimated using a validated questionnaire. RESULTS: Prevalence of allergy history was significantly higher in DF-PAL and in NF-PAL than in controls. Polysensitization, and sensitization to seasonal and food allergens were more frequent in DF-PAL than in DF-controls, respectively: 13.8% vs 1% (adjusted odds ratio (aOR): 17.5 (2.2-134), 11.9% vs 3.1% (aOR: 4.4 (1.2-7.2) and 16.8% vs 4.1% (aOR: 5.2 (1.7-7.2)). The prevalence of atopy markers was similar between NF-PAL patients and NF-controls. CONCLUSIONS: PAL in farmers is associated with a high rate of markers of atopy, supporting atopy as a risk indicator. Clinical trial registered with ClinicalTrials.gov (NCT02540408).

Microbial exposure to dairy farmers' dwellings and COPD occurrence.

Dairy farming is a risk factor for chronic obstructive pulmonary disease (COPD). The aim was to determine predictive markers either in blood samples or in dwelling dust samples by comparing COPD and healthy controls with or without farming activity. Dust was collected and analyzed by real-time quantitative PCR. ELISA and DELFIA® were performed to assay the level of specific IgG and IgE of 10 targeted microorganisms. The dwelling exposure of farmers was higher than in the non-farmers (Especially Eurotium amstelodami and Lichtheimia corymbifera). The IgG response against Wallemia sebi and Saccharopolyspora rectivirgula was more often higher in the farmers than the non-farmers. However, exposure and sensitization to the microorganisms tested cannot explain the occurrence of COPD in the dairy farmers' population. COPD development is probably caused by multiple factors associated with exposure over a period of several years.

Anxiety and depression among dairy farmers: the impact of COPD.

Background: Chronic obstructive pulmonary disease (COPD) and farming are two conditions that have been associated with an increased risk of anxiety and depression. Dairy farming is an independent risk factor for COPD. Objective: To test the hypotheses that the prevalence of anxiety and/or depression is higher in dairy farmers with COPD than in farmers without COPD, and higher in dairy farmers with COPD than in non-farmers with COPD. Methods: Anxiety and depression were evaluated using the Hospital Anxiety and Depression Scale in 100 dairy farmers with COPD (DF-COPD), 98 dairy farmers without COPD (DF-controls), 85 non-farming patients with COPD (NF-COPD) and 89 non-farming subjects without COPD (NF-controls), all identified by screening in the Franche-Comté region of France. Anxiety and depression were considered present when the Hospital Anxiety and Depression Scale score was ≥8. COPD was defined by a post-bronchodilator forced expiratory volume in 1 second/forced vital capacity ratio <0.7. Results: The crude prevalence of anxiety did not differ between the four groups, ranging from 36% in NF-controls to 47% in NF-COPD (p=0.15 between groups). Similarly, the prevalence of depression did not differ significantly between the four groups (p=0.16 between groups). In dairy farmers (n=198), the only factors associated with anxiety were quality of life and current smoking. Depression in dairy farmers was associated with airflow limitation (lower forced expiratory volume in 1 second and COPD grade 2 or more) as well as with some COPD-related features (dyspnea severity, current smoking, and poorer quality of life). In non-farmers, both anxiety and depression were associated with airflow limitation and COPD-related features. Conclusion: In our population, the prevalence of anxiety and/or depression was similar in dairy farmers with and without COPD and in non-farmers with COPD. Nevertheless, the degree of airway obstruction and some COPD-related features were associated with depression among dairy farmers, whereas these factors were not associated with anxiety.

Case-Finding for Persistent Airway Obstruction in Farmers: A Questionnaire With Optimal Diagnosis Criteria.

INTRODUCTION: Appropriate identification of subjects who are candidates for spirometry through case-finding questionnaires may help solve the problem of chronic obstructive pulmonary disease misdiagnosis. The performance of case-finding questionnaires depends at least partially on the characteristics of the population used for their development. The use of an accurate threshold for the forced expiratory volume in 1 second / forced vital capacity ratio to define persistent airway obstruction is also vital in ascertaining chronic obstructive pulmonary disease. METHODS: Using a population examined between October 2012 and May 2013 that included a large subset of agricultural workers both exposed and unexposed to tobacco smoking, the authors aimed to select a combination of items that would identify persons most likely to have persistent airway obstruction defined as forced expiratory volume in 1 second / forced vital capacity less than the lower limit of normal according to the Global Lung Initiative-2012 equations. Two thirds of the population (n=3,397) were randomly selected to develop a questionnaire, and one third (n=1,698) was reserved for questionnaire validation. Statistical analysis was performed in 2016. RESULTS: The selected items were sex, dyspnea, BMI, tobacco smoking habits, age, history of respiratory diseases, and history of occupation at risk. The C-index of the model was 0.84 (95% CI=0.80, 0.88) for the development population and 0.76 (95% CI=0.66, 0.86) for the validation population. Using the selected items in combination, the sensitivity and specificity in identifying persistent airway obstruction were 76% and 77%, respectively, in the development population (and 68% and 73%, respectively, in the validation population) for a threshold value of 2.50%. CONCLUSIONS: This seven-item questionnaire is the first developed from a population comprising a large subset of agricultural workers and using the Global Lung Initiative-2012 equations.

Smoking habits in French farmers: a cross-sectional study.

BACKGROUND: Farmers are exposed to multiple air contaminants that may interact with tobacco smoking in the development of respiratory diseases. Farmers are currently considered to smoke less than non-farmers, but precise data in different categories of age and farming activities are lacking. METHODS: Smoking habits were studied in a cross-sectional study involving 4105 farmers and 996 non-farming controls aged 40-74 years in 9 French departments between October 2012 and May 2013. Three age groups were defined (40-54, 55-64 and 65-74years). Farmers were divided into four activity groups, namely cattle breeders, livestock farmers working in confined spaces, crop farmers and others. Smoking prevalence was compared between farmers and controls, and odds ratios (ORs) for smoking adjusted for age were calculated. RESULTS: The adjusted OR for ever-smoking was lower among farmers than among non-farmers in all age categories, but the ORs for current smoking were similar in farmers and controls. Smoking prevalence varied according to the type of farming activity, and was lower than in non-farming controls only among cattle breeders and confined livestock farmers. In farmers, the proportion of smokers was higher in the youngest age categories compared with the older age classes. CONCLUSIONS: Our results confirm that the prevalence of ever-smokers is lower in farmers than in non-farmers. Nevertheless, our data show that active smoking prevalence is similar in farmers and in non-farmers. This suggests that farmers, just like non-farmers, should be targeted by primary prevention campaigns against smoking.

Prevalence and risk factors for COPD in farmers: a cross-sectional controlled study.

There are conflicting data regarding the magnitude and determinants of chronic obstructive pulmonary disease (COPD) risk in farmers.In a cross-sectional study of 917 nonfarming working controls and 3787 farmers aged 40-75 years, we assessed respiratory symptoms, tobacco exposure, job history (without direct exposure measurement) and lung function. COPD was defined by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criterion (post-bronchodilator forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) <0.70) and by the Quanjer reference equation (post-bronchodilator FEV1/FVC

Impact of farm modernity on the prevalence of chronic obstructive pulmonary disease in dairy farmers.

Dairy farming is associated with an excess of chronic obstructive pulmonary disease (COPD). The dairy industry has been changing for the past three decades with larger, more efficient farms and potentially less exposure to agents involved in COPD development. However, the impact of farm modernisation on COPD prevalence is unknown. We studied respiratory symptoms, respiratory function by spirometry and tobacco smoking in 575 male dairy farmers working either in traditional or in modern farms in the French Doubs region. COPD was defined by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criterion (forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC) <0.70) and by the Quanjer reference equation (FEV1/FVC

Predictors of early cessation of dairy farming in the French Doubs province: 12-year follow-up.

BACKGROUND: A healthy worker effect due to respiratory disability has been noted in the farming population, but other factors may also interfere. Little has been published about factors influencing the early cessation of work in self-employed dairy farmers. METHODS: Two hundred and nineteen dairy farmers were included from a cohort constituted in eastern France in 1993-1994 with a 12-year follow-up. Spirometric data, personal, and farm characteristics were registered. Cox models with delayed entry in which age was the time-scale were applied to identify the baseline predictive factors of the early cessation of dairy farming. RESULTS: Working in a modern farm was protective against early cessation of dairy farming (hazard ratio: 0.36 [95% CI: 0.16-0.81]), especially in men. Having asthma was a predictive factor of early cessation, especially in women (hazard ratio: 16.12 [95% CI: 3.28-79.12]). CONCLUSIONS: The most predictive factors of early cessation of dairy farming were health related in women and farm related in men.

[Alveolar echinococcosis: from an incurable rural disease to a controlled urban infection]. / Echinococcose alvéolaire : d'une maladie rurale incurable à une infection urbaine sous contrôle ?

Human alveolar echinococcosis is a parasitic zoonosis with intermediate (rodents and small lagomorphs) and final (carnivores) hosts. The latter can transmit the parasite to humans, by their feces, which are contaminated by the oncospheres of Echinococcus multilocularis, the larvae of which develop in the liver like a slow cancer. Political, socioeconomic, and ecological factors can affect the intermediate and final hosts and thus influence the long-term emergence and stability of endemic areas. The past 20 years have been marked by: Epidemiologic changes: discovery of an endemic area in China, the largest in the world; extension of the European endemic range to the east and north; extension of the French endemic range to the west and south; and the settlement of contaminated foxes in urban centers, which will modify the populations at risk over time. Progress in diagnosis: initial use of liver ultrasound to screen for asymptomatic disease; value of magnetic resonance imaging to confirm diagnosis and assess extension of disease before beginning treatment; mastery of immunological and genetic diagnosis; and the introduction of positron emission tomography combined with computed tomography to assess the functional activity of the lesions and monitor treatment. Consensus has defined the main directions of a multidisciplinary treatment approach: radical liver resection when possible; avoidance of palliative surgical procedures; use of interventional radiology or endoscopy to treat biliary and vascular complications, whenever possible; consideration of liver transplantation only when all other treatment possibilities have been exhausted; and treatment of all patients, without exception, by albendazole for at least two years after radical surgery and long term (at least several years) in other cases. In France, survival and quality of life have improved very substantially, due to earlier diagnosis, clinical classification of cases, and rigorous follow-up as part of the FrancEchino network. Better understanding of the immunological and immunogenetic mechanisms that underlie the course of disease may open up the possibility of immunomodulation that could replace or round out the current treatments. These are far from satisfactory, in view of the constraints of prolonged, most often life-long treatment by benzimidazoles and their side effects.

[Lung diseases in farmers]. / Pathologies respiratoires en milieu agricole.

Respiratory diseases in farmers are complex and intricate diseases. Their diagnosis, management and treatment are difficult and their social and financial consequences can be painful. Respiratory diseases include: hypersensitivity pneumopathies, the most frequent and recognized one being farmer's lung disease; agricultural chronic bronchitis; allergic or non-allergic asthmas and rhinitis; and toxic bronchopneumopathies, of which organic dust toxic syndrome (or dust fever) is the most common, especially in animal breeding environments. The purpose of this article is to shortly describe these diseases, indicate their frequency and the main elements of their management: treatments and prevention methods.

Farmer's lung disease and microbiological composition of hay: a case-control study.

Previous studies performed in France have suggested that handling hay contaminated with high amounts of moulds, and especially Absidia corymbifera and Eurotium amstelodami, may favour farmer's lung disease. The circumstances favouring farmer's lung disease and the distinctive microbiological composition of hay samples that provoke attacks need to be specified. We present a case-control study which investigates the agricultural practices and the microbiological composition of hay handled in patients with farmer's lung disease as compared to those of a representative control population. Ten cases identified the hay they were handling at the onset of symptoms. The location, type of farm and working conditions were similar to those of the control farms. Conversely, the microbiological composition of hay differed, with significantly higher amounts of E. amstelodami (P < 0.01), A. corymbifera (P = 0.003), mesophilic Streptomyces (P < 0.01), thermophilic Streptomyces (P < 0.01) and Saccharomonospora viridis (P < 0.01) than in the control population. Our results demonstrate that hay identified by patients as having a harmful effect is characterized by a higher total amount of microorganisms, notably five microorganisms that seem discriminative. Mean concentrations are 2- to 115-fold higher in hay suspected to cause symptoms than in hay from a representative panel of farms. Handling hay with high amounts of these five microorganisms constitutes a risk factor for farmer's lung disease that should be considered for the development of prophylactic measures.

Evaluation of salting as a hay preservative against farmer's lung disease agents.

Salting is a traditional, empirical practice used commonly in dairy farming regions to prevent moulding and heating in hay. Our aim was to evaluate the effect of salting hay on the proliferation of microorganisms, particularly thermophilic actinomycetes and moulds involved in farmer's lung disease. Fifty-one pairs of salted and unsalted hay bales from 14 farms were produced during the haymaking season between March and July. Both the salted and the unsalted bales came from the same field, and were packed and stored under identical conditions. Sampling was performed by microbiological analysis including 6 culture media during the winter following salting (January-February). The use of salt did not significantly decrease the amount of Saccharopolyspora rectivirgula , the actinomycetes most commonly involved in farmer's lung disease, or that of Absidia corymbifera, Eurotium amstelodami and Wallemia sebi , three moulds responsible for farmer's lung disease in eastern France. Our results are important in that they can inform farmers and dispel the false sense of security induced by salting, which is reinforced by the misconception that palatable hay is healthy hay.