Most people are affected by respiratory infections every year, and approximately 800,000 Danes live with asthma and/or chronic obstructive pulmonary disease (COPD). Several studies have shown that air pollution from livestock farms can lead to various health issues, including lung diseases and respiratory infections. Therefore, there is a risk that living close to a livestock farm can cause health consequences for the lungs and airways. In Denmark, there are approximately 13,000 livestock farms with dairy cows, beef cattle, pigs, and poultry. The Danish pig production is substantial, with around 17.5 million slaughtered pigs annually.
The role of residential proximity to livestock farms on health consequences has been studied before, though with contradicting results. No major Danish studies have yet thoroughly examined this issue. This research aims to enhance our understanding of the potential health consequences for lungs and airways associated with living near livestock facilities.
Purpose
The project consists of two register-based sub-studies with the following aims:
- To investigate the association between proximity to livestock farms and the risk of asthma among children aged 0-6 years in the period 1999-2022.
- To examine the relationship between proximity to livestock farms and the risk of exacerbation of asthma, chronic obstructive pulmonary disease (COPD), or respiratory infections in the Danish population aged 30 years or older during the period of 1998-2022.
Proximity to livestock farms is estimated for everyone’s residential address. The exposure to livestock farms is further developed, by examine the difference in risk, according to when in life and for how long you are exposed, the number of animals at and distance to each livestock farm and the type of animal at each livestock farm (e.g. cattle, pigs, poultry and mink).
Method
It is a register-based cohort study, including individuals living outside of larger cities in Denmark in the period of 1997-2022. The study include data on livestock farms (1993-2022), residential addresses and from hospital contacts, dispensed prescription medication and civil registration system at an individual level.
Incident asthma is analyzed using a Poisson regression model and exacerbation of disease is analyzed using a logistic regression model. Being exposed to livestock farms in the neighborhood will be modelled using different exposure definitions, e.g. distance to nearest livestock farm. The analyses are adjusted for sex, socioeconomic differences, and parents’ asthma status.
Project period
Spring 2023 to end 2024.
Collaboration and funding
Department of Veterinary- and animal sciences, University of Copenhagen.
Financed by Karen Elise Jensen Foundation.