Exposure to dog allergens could worsen asthma outcomes

Dogs can be a source of joy for many children. They can teach responsibility and be the origin of fond memories. However, for children who have asthma the exposure to dog allergens could mean worse respiratory outcomes, according to a research letter in Pediatric Allergy and Immunology.¹

Investigators did a secondary data analysis using the DISCOVER (Domestic Indoor Particulate Matter and Childhood Asthma Morbidity) longitudinal observational cohort study. The study included children aged 5 to 12 years who were from inner city Baltimore. They had been diagnosed with asthma by a doctor. Each participant was assessed at the time of recruitment as well as 3, 6, and 9 months. At each follow-up appointment, the child was examined for respiratory outcomes and the home environment was assessed for dog allergen concentrations, which meant Can f 1 concentrations measured in home dust, and dog presence, which meant evidence of dogs observed on home inspection.

There were 162 children included in the study and the majority were African American. Roughly 65% had persistent asthma. The baseline prevalence of dog presence was 36%. The distribution and prevalence of exposures were 0.08 µg/g-9.88% for the bedroom; 0.04 µg/g-8.13% for the bedroom floor; and 0 µg/g- 11.8% for the kitchen. To understand the interaction between respiratory outcomes and specific allergen exposure, researchers stratified the population into 4 categories that were based on dichotomous allergen exposure status at different sites.

They found that the presence of a dog was not significantly linked to worse respiratory outcomes. After taking into account dog allergen, dog-associated non-allergen exposures that were from the residual effect of dog presence were linked to lower odds of absence from school and nocturnal asthma symptoms. Overall, dog-associated non-allergen exposure may be linked to lower asthma morbidity and dog allergen exposure was linked with worse asthma control.

Reference:

1. Tsou P, McCormack MC, Matsui EC, et al. The effect of dog allergen exposure on asthma morbidity among inner‐city children with asthma. Pediatric Allergy and Immunology. 2019;31(2):210-213. doi:10.1111/pai.13144