CHILDHOOD contact with dogs and farm animals reduces the risk of children developing asthma, according to new research from Sweden. Previous studies have linked a range of environmental factors with the development of asthma, including tobacco smoke exposure, animal contact, infections, and family size. The new research is timely as childhood asthma has been rising in recent decades and currently affects almost 10% of American children. If left untreated, asthma can often cause children to reduce their physical activity, which carries its own health risks.
The new study included over 1 million Swedish children born between 2001 and 2010. The research team analysed the association between childhood exposure to animals, specifically pet dogs in the home, and the development of asthma. Of those included in the study, 5% of the preschool-aged children had an asthmatic event before baseline and 28,511 cases of asthma were seen in the follow-up period. The results showed that exposure to a dog in the first year of a child’s life was associated with a 13% reduction in the risk of asthma by the time the child reached school age. In addition, exposure to farm animals was associated with a 31% reduction in the risk of developing asthma by preschool age, and a 52% reduction in the risk of developing asthma by school age.
The research team explained that children who are exposed to animals are also exposed to elevated amounts and a greater diversity of microorganisms and endotoxins, which may influence the development of their immune system. The results have implications for the many countries that share similar cultural relationships regarding pet ownership and farming with Sweden.
Dr Tove Fall, Uppsula University, Uppsula, Sweden, said: “For what we believe to be the first time in a nationwide setting, we provide evidence of a reduced risk of childhood asthma in 6-year-old children exposed to dogs and farm animalsThis information might be helpful in decision making for families and physicians on the appropriateness and timing of early animal exposure.”