Clinical trial NCT02540408: Detection and Characterization of COPD in Dairy Farmers
Official title: COPD in Dairy Farmers: Screening, Characterization and Constitution of a Cohort. The BALISTIC Study
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Chronic Obstructive Pulmonary Disease (COPD)
Environmental Exposure
Keywords: Occupational COPD
Pathophysiology
Exercise limitation
Pulmonary hyperinflation
Arterial stiffness
Lead sponsor: Centre Hospitalier Universitaire de Besancon
Sponsor class: OTHER
First posted: 2015-09-04
Enrollment: 400
Sex: ALL
Minimum age (years): 40
Maximum age (years): 74
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: CASE_CONTROL
Time perspective: PROSPECTIVE
Sampling method: PROBABILITY_SAMPLE
Study population: COPD patients will be defined according to the GOLD criteria (post-bronchodilator FEV1/FVC ratio\<70%).

Healthy subjects must have pre-bronchodilator FEV1/FVC ratio \>75% and pre-bronchodilator FEV1 \>95% of predicted value.

Brief summary: A pilot study from the investigators group suggests that the prevalence of chronic obstructive pulmonary disease (COPD) among dairy farmers is higher than in the general population. Most characteristics of COPD in dairy farmers (smoking habits, dyspnoea, quality of life, lung function, bronchial exhaled nitric oxide, systemic inflammation, arterial stiffness and exercise capacity) are largely unknown. Although immunization against organic dusts is suspected, the pathophysiology of COPD in dairy farmers is also unknown.

This study therefore aims at (i) comparing the prevalence of COPD in dairy farmers and in subjects without any occupational exposure (control arm) through a vast COPD detection program in the Franche-Comté region; (ii) comparing several characteristics (smoking habits, dyspnoea, quality of life, lung function, bronchial exhaled nitric oxide, systemic inflammation, arterial stiffness and exercise capacity) between dairy farmers with COPD and patients with COPD without any occupational exposure; (iv) identifying etiological factors of COPD in dairy farmers (comparison of exposure and specific immunoglobulin E between dairy farmers with COPD and dairy farmers with normal pulmonary function tests); and (v) constituting a cohort of COPD patients and control subjects for further longitudinal studies.

Data from selected patients (either current or former smokers) with mild COPD and from matched controls will also be analyzed in an ancillary study which objectives are to compare exercise tolerance, ventilatory constraints on tidal volume expansion and dyspnoea between asymptomatic mild COPD subjects, symptomatic mild COPD and healthy controls.

Detailed description: 2000 dairy workers and 2000 subjects without any occupational exposure, all aged 40 to 74 years, will take part to a COPD screening program (spirometry and bronchodilation test) between September 2011 and October 2014.

Subjects with COPD and healthy matched controls will attend a second visit. If needed, COPD subjects will be asked to stop any respiratory related medication such as short and long acting bronchodilators 72 hours prior to the visit. All subjects will complete several questionnaires (quality of life, respiratory symptoms, smoking habits,...). A complete medical history will be collected, and a blood sample will be taken. Subjects thereafter will complete arterial stiffness measurement, exhaled nitric oxide and pulmonary function testing pre- and 30-min post-bronchodilator. A symptom-limited incremental cycle exercise test will be performed on the same day, at least 6 hours after the bronchodilator test and at least 4 hours after the meal.

Exposure to organic dusts will be quantified through analyze of electrostatic wipes left at subjects' homes for 10 weeks.

Eligibility criteria: Inclusion Criteria:

* subject aged 40-74 years
* either dairy farmer or unexposed to any occupational risk factor for COPD

Exclusion Criteria:

* COPD in GOLD stage 4
* pregnancy
* treatment with systemic corticosteroids
* established diagnosis of asthma
* established diagnosis of bronchiectasis
* established diagnosis of allergic alveolitis

Primary outcomes:
measure: prevalence of COPD in dairy farmers and in unexposed subjects
timeFrame: 3-year
Secondary outcomes:
measure: comparison of smoking habits between dairy farmers with COPD and unexposed COPD
timeFrame: 4-year
measure: comparison of dyspnoea between dairy farmers with COPD and unexposed COPD
timeFrame: 4-year
measure: comparison of lung function between dairy farmers with COPD and unexposed COPD
timeFrame: 4-year
measure: comparison of bronchial exhaled nitric oxide between dairy farmers with COPD and unexposed COPD
timeFrame: 4-year
measure: comparison of systemic inflammation between dairy farmers with COPD and unexposed COPD
timeFrame: 4-year
measure: comparison of arterial stiffness between dairy farmers with COPD and unexposed COPD
timeFrame: 4-year
measure: comparison of exercise capacity between dairy farmers with COPD and unexposed COPD
timeFrame: 4-year
measure: comparison of exposure to organic dusts between dairy farmers with and without COPD
timeFrame: 3-year
measure: comparison of immunization to organic dusts between dairy farmers with and without COPD
timeFrame: 3-year
Other outcomes:
measure: comparison of dyspnoea between asymptomatic mild COPD subjects, symptomatic mild COPD and healthy controls
timeFrame: 2-year
measure: comparison of exercise tolerance dyspnoea between asymptomatic mild COPD subjects, symptomatic mild COPD and healthy controls
timeFrame: 2-year
measure: comparison of ventilatory constraints on tidal volume expansion between asymptomatic mild COPD subjects, symptomatic mild COPD and healthy controls
timeFrame: 2-year
measure: cardiovascular risk in COPD patients either never-smokers or current/former smokers
timeFrame: 3-year
Locations:
city: Besançon
country: France
facility: CHU Jean Minjoz
Study officials:
affiliation: CHU Besançon
name: Bruno Degano, MD, PhD
role: PRINCIPAL_INVESTIGATOR
affiliation: CHU Besançon
name: Jean-Charles Dalphin, MD, PhD
role: STUDY_CHAIR
References:
citation: Degano B, Bouhaddi M, Laplante JJ, Botebol M, Annesi-Maesano I, Marescaux A, Roux P, Thaon I, Wolf JP, Regnard J, Dalphin JC. [COPD in dairy farmers: screening, characterization and constitution of a cohort. The BALISTIC study]. Rev Mal Respir. 2012 Nov;29(9):1149-56. doi: 10.1016/j.rmr.2012.08.007. Epub 2012 Oct 15. French.
citation: Veil-Picard M, Soumagne T, Vongthilath R, Annesi-Maesano I, Guillien A, Laurent L, Andujar P, Roche N, Jouneau S, Cypriani B, Laplante JJ, Degano B, Dalphin JC. Is atopy a risk indicator of chronic obstructive pulmonary disease in dairy farmers? Respir Res. 2019 Jun 17;20(1):124. doi: 10.1186/s12931-019-1082-2.