Having a cat at home doesn't appear to worsen asthma in children with allergies, a large Swedish study finds. Researchers compared over 30,000 kids and found no significant difference in asthma exacerbations, severity, or lung function between those with and without cat exposure. One possible explanation: kids may already be exposed to cat allergens at school or on public transit.
A large nationwide study out of Sweden suggests that kids with asthma and allergies who live with cats fare no worse than those without feline housemates. Published in Frontiers in Allergy, the study tracked over 30,000 pediatric patients aged 4–17 and found no meaningful difference in asthma exacerbations, severity, lung function, or asthma control between those with and without cat exposure.
Researchers from Karolinska Institutet analyzed data from multiple Swedish national health registries, comparing 2,862 children in cat-owning households to 27,415 without cat exposure. Even after adjusting for factors like age, sex, parental asthma history, and socioeconomic status, the outcomes remained strikingly similar. Notably, the number of cats, their sex, and their age also had no bearing on asthma outcomes.
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Why it matters: Clinicians often advise families with asthmatic children to avoid pets, but this first large-scale epidemiological study in pediatrics challenges that blanket guidance. Since cat allergens are widespread in shared spaces like schools and buses, removing a cat from the home may offer less protection than previously assumed.
