Asthma is the most common chronic disease and one of the leading causes of hospitalization in children. The Global Asthma Network estimates the global prevalence of asthma to be 9.1% in children and 11.0% in adolescents, but these rates vary widely by country, region, and setting. Worldwide, the highest prevalence of childhood asthma (more than 20%) occurs in parts of the British Isles, Oceania and the Middle East. Known risk factors for developing asthma include exposure to air pollution and smoking, childhood viral infections, obesity, and pre-existing allergies such as eczema and hay fever.
Patients self-report that exposure to animal dander appears to trigger asthma attacks. However, clinical and epidemiological data on this have so far been conflicting, with most coming from small studies on subgroups that are not necessarily representative of the broader population. Currently, researchers are Allergy frontier Sharing a home with a cat does not seem to worsen outcomes for children with asthma or allergies.
“Here, in a national cohort of Swedish children with asthma and allergies, we show that asthma severity, exacerbations, asthma control, and lung function in children living with cats are similar in the short term to children living without cats,” said lead author Lessie R. Putri, Ph.D., a postdoctoral researcher at the Karolinska Institute in Stockholm.
We also found no differences in asthma outcomes related to number of cats, cat sex, or cat age. ”
Dr. Resti R. Putri, Karolinska Institutet, Stockholm
large pediatric sample
In 2023, Putri and colleagues began a study of a cohort of 30,277 children between 2006 and 2020 who were diagnosed with asthma or airway allergies and were between 4 and 17 years old at the time. They tracked these over a 24-month period up to 2024, pulling records on diagnoses, emergency visits, prescribed medications, asthma control tests and spirometry tests from linked data in the Swedish National Patient Register, Prescription Drug Register and National Airway Register to track asthma outcomes.
In Sweden, all pet cats born after 2008 must be registered in the national cat register from 2023. For each child, the authors looked at whether the parent household owned at least one cat in 2023, which was the case for 9.4% of children.
Cats don’t worsen asthma in children
The results showed that there was no significant association between exposure to pet cats and asthma outcomes. For example, moderate to severe asthma based on prescribed asthma medications occurred in 9.6% of cat-exposed children and 10.1% of unexposed children. Asthma “exacerbations” (also known as attacks or flares) occurred in 3.3% of children exposed to cats and 3.5% of unexposed children.
Of the subset of 1,428 children for whom asthma control and spirometry data were available, 97 (6.8%) lived with a cat. There were no significant differences between the two groups on two common measures of lung function.
“One possible explanation is that exposure to cat allergens is very common even outside the home. Even children without cats at home may still be exposed in shared environments such as school or public transport, which may explain why we did not see a difference,” Putri said.
“While these large-scale findings provide valuable insight, there was a lack of data on which allergens children were sensitized to. Also, because the National Cat Registry is relatively new, some children living with cats may have been incorrectly classified as unexposed,” she warned.
