MedicalResearch.com Interview with:
Catarina Almqvist Malmros MD, PhD
Professor | Consultant Pediatrician
Dept of Medical Epidemiology and Biostatistics | Karolinska Institutet
Lung and Allergy Unit | Astrid Lindgren Children’s Hospital
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: We have previously shown an association between growing up with dogs and a lower risk of childhood asthma (doi: 10.1001/jamapediatrics.2015.3219) but it has been unknown whether this link is modified by characteristics of the dog. Sex of the dog may have an effect on expressed allergens, and uncastrated male dogs release more of a certain allergen than castrated male dogs and female dogs. Some breeds are also described as ‘hypoallergenic’, but there is no scientific evidence whether they are more suitable for people with allergies.
We examined how variables such as sex, breed, number of dogs or size of dog are associated with the risk of asthma and allergy among children with a dog in their home during the first year of life. We included all Swedish children born between January 2001 and December 2004 whose parents had a registered dog in a dog-owner register and linked the data to the Swedish population- and health data registers.
Main findings are that children raised with only female dogs at home had a 16 per cent lower risk of asthma than those with male dogs, and that children living with two or more dogs had a 21 per cent lower risk of asthma than those with only one dog. Importantly, families with parental asthma or allergies had ‘hypoallergenic’ breeds more often than children whose parents did not have asthma or allergies; 11.7% compared to 7.6 . Exposure to these breeds was associated with a 27 per cent higher risk of allergy and no decreased risk of asthma. Continue reading