Children who grew up together with a pet dog have a 15 per cent reduced risk of acquiring asthma according to a new research. In this study, over a million children and two dog ownership registers were included.
Researchers determined if there is a causal relationship between respiratory disease, particularly asthma, and early exposure to animals. The group found that there is a 52 percent reduced risk for children growing with registered farm-animal workers.
"Earlier studies have shown that growing up on a farm reduces a child's risk of asthma to about half. We wanted to see if this relationship was true also for children growing up with dogs in their homes," Epidemiology assistant professor Tove Fall from the Uppsala University said. This study likely supports the "hygiene hypothesis" that postulates that early exposure to microorganisms can desensitize the immune system, making it less likely to be triggered by allergies and autoimmune attacks.
The team cross linked the Swedish national medical record system and the dog-licence register to determine the cause and effect of having a dog in the first year of a child's life and the incidence of asthma up to age six. Fall found that those who grew up with a pet have 15 per cent less chance to suffer asthma by the time they go to school than those who do not have a dog. Also, the team could account for other contributing factors such as place of residence, socioeconomic status and asthma in parents as they had access to a national databank with over a million children born between 2001 and 2010 in Sweden.
Fall made clear though that having both a pet and a child is nothing to be worried about for parents; but, raising a pet after a child has already developed asthma is a totally different story. Clinical epidemiologist of Karolinska Institute Catarina Almqvist Malmros made clear that some children develop allergic reactions to dogs and cats and contact with them is to be avoided.
"These kinds of epidemiological studies look for associations in large populations but do not provide answers on whether and how animals could protect children from developing asthma," Malmros said. "We know that children with an established allergy to cats or dogs should avoid them, but our results also indicate that children who grow up with dogs in their home have reduced risks of asthma later in life."
