title: Increased respiratory symptoms in COPD patients living in the vicinity of livestock farms.
abstract: Several studies have investigated the effect of livestock farm emissions on the respiratory health of local residents, but results are inconsistent. This study aims to explore associations between the presence of livestock farms and respiratory health in an area of high-density livestock farming in the Netherlands. We focused especially on associations between farm exposures and respiratory symptoms within subgroups of potentially susceptible patients with a pre-existing lung disease.In total, 14 875 adults (response rate 53.4%) completed a questionnaire concerning respiratory health, smoking habits and personal characteristics. Different indicators of livestock farm exposures relative to the home address were computed using a geographic information system.Prevalence of chronic obstructive pulmonary disease (COPD) and asthma was lower among residents living within 100 m of a farm (OR 0.47, 95% CI 0.24-0.91 and OR 0.65, 95% CI 0.45-0.93, respectively). However, >11 farms in 1000 m compared to fewer than four farms in 1000 m (fourth quartile versus first quartile) was associated with wheezing among COPD patients (OR 1.71, 95% CI 1.01-2.89). Using general practitioners' electronic medical records, we demonstrated that selection bias did not affect the observed associations.Our data suggest a protective effect of livestock farm emissions on the respiratory health of residents. Nonetheless, COPD patients living near livestock farms reported more respiratory symptoms, suggesting an increased risk of exacerbations.
authors.affiliation: Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands Institute for Health Services Research (NIVEL), Utrecht, The Netherlands f.borlee@uu.nl.
authors.forename: Floor
authors.initials: F
authors.lastname: Borlée
authors.affiliation: Institute for Health Services Research (NIVEL), Utrecht, The Netherlands.
authors.forename: C Joris
authors.initials: CJ
authors.lastname: Yzermans
authors.affiliation: Institute for Health Services Research (NIVEL), Utrecht, The Netherlands.
authors.forename: Christel E
authors.initials: CE
authors.lastname: van Dijk
authors.affiliation: Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.
authors.forename: Dick
authors.initials: D
authors.lastname: Heederik
authors.affiliation: Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.
authors.forename: Lidwien A M
authors.initials: LA
authors.lastname: Smit
mesh_terms: D000328:Adult; D000368:Aged; D000383:Agriculture / Q000706:statistics & numerical data*; D000818:Animals; D001249:Asthma / Q000453:epidemiology*; D003430:Cross-Sectional Studies; D018450:Disease Progression; D004781:Environmental Exposure / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D058751:Livestock; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D017711:Nonlinear Dynamics; D015995:Prevalence; D029424:Pulmonary Disease, Chronic Obstructive / Q000453:epidemiology* / Q000503:physiopathology; D012111:Residence Characteristics / Q000706:statistics & numerical data*; D065631:Rhinitis, Allergic / Q000453:epidemiology*; D012307:Risk Factors; D012424:Rural Population / Q000706:statistics & numerical data; D012720:Severity of Illness Index; D012907:Smoking / Q000453:epidemiology*; D011795:Surveys and Questionnaires