Early contact with dogs linked to lower risk of asthma
Tove Fall is Assistant Professor in Epidemiology at the Department of Medical Sciences, SciLifeLab/Uppsala University. Foto: Mikael Wallerstedt
A team of Swedish scientists have used national registries encompassing more than one million Swedish children to study the association between early life contact with dogs and subsequent development of asthma. This question has been studied extensively previously, but findings have been inconclusive. The new study found that children who grew up with dogs had about 15 percent lower risk of asthma than children without dogs.
A total of more than one million children were included in the researchers’ study linking together nine different national data sources, including two dog ownership registers not previously used for medical research. The results are being published for the first time in JAMA Pediatrics. The goal was to determine whether children exposed to animals early in life are at different risk of asthma.
‘Earlier studies have shown that growing up on a farm reduces a child’s risk of asthma by about half. We wanted to see if this relationship also was true also for children growing up with dogs in their homes. Our results confirmed the farming effect, and we also saw that children who grew up with dogs had about 15 percent less asthma than children without dogs. Because we had access to such a large and detailed data set, we could account for confounding factors such as asthma in parents, area of residence and socioeconomic status’ says Tove Fall, Assistant Professor in Epidemiology at SciLifeLab/Uppsala University. She coordinated the study together with researchers from Karolinska Institutet in Stockholm, Sweden.
’Dog and farm animal exposure reduce risk of childhood asthma – a nationwide cohort study‘. Tove Fall, Cecilia Lundholm, Anne K Örtqvist, Katja Fall, Fang Fang, Åke Hedhammar, Olle Kämpe, Erik Ingelsson, and Catarina Almqvist. JAMA Pediatrics. In press.