No link between cat ownership and asthma flare-ups in children

By Dr. Priyom Bose, Ph.D.Reviewed by Lauren HardakerJun 12 2026

A nationwide study of more than 30,000 children found that living with cats was not linked to worse asthma control, lung function, or flare-ups, challenging long-standing concerns about cat ownership in families managing childhood asthma. 

Study: Cat exposure and asthma outcomes in a cohort of children with asthma and allergy. Image credit: Anna Nass/Shutterstock.com

A recent study in Frontiers in Allergy evaluated the association between cat exposure and asthma outcomes in children with established asthma and allergy.

Cat ownership remains controversial in asthma 

Asthma is a chronic respiratory disease characterized by airway inflammation and hyperresponsiveness, frequently affecting children worldwide. Environmental exposures, notably contact with companion animals, are increasingly recognized as key factors influencing asthma management. Although furry animals are often assessed collectively in risk evaluations, distinct allergen profiles and patterns of human-animal interaction across species can lead to variable impacts on asthma morbidity.

Despite the high prevalence of cat ownership in Europe, clinical recommendations for managing cat exposure in children with asthma are inconclusive. The majority of existing research has focused on the impact of early-life cat exposure on the risk of developing asthma or allergic rhinitis, with relatively little attention paid to the effects of ongoing exposure in children already diagnosed with asthma.

Current evidence regarding the relationship between cat exposure and asthma morbidity in this population is inconsistent. Some studies report no independent association, while others implicate sensitization and viral infections as more critical determinants.

Notable research gaps include limited sample sizes, selective recruitment, and a predominant reliance on self-reported clinical outcomes. Furthermore, the effects of specific cat characteristics on domestic allergen load and subsequent asthma morbidity have not been sufficiently examined. As a result, it remains uncertain whether these factors meaningfully influence asthma outcomes, highlighting the necessity for comprehensive, population-based studies that address these methodological limitations.

Does cat exposure influence asthma outcomes in children?

The current cross-sectional cohort study included all children born in Sweden between 2006 and 2020, aged 4 to 17 years, who had established asthma and airway allergies. Asthma and allergic rhinitis diagnoses were confirmed using validated algorithms based on diagnosis and medication codes. Children were excluded if they had emigrated, died, or lacked parental sociodemographic data.

Cat exposure was defined as any recorded parental cat ownership during 2023. Asthma outcomes were tracked during 2023 and 2024, focusing on asthma exacerbations, asthma severity, asthma control test (ACT) scores, and forced expiratory volume in 1 second (FEV1).

Asthma exacerbation was defined as either an emergency or unplanned hospital visit or a specialized care visit for asthma, or four or more dispensations of short-acting beta-2-agonists (SABAs) within a year. Moderate-to-severe asthma was classified using dispensed asthma medications and the adapted Global Initiative for Asthma (GINA) treatment steps.

Children were considered to have moderate-to-severe asthma if they received more than one controller medication, such as a combination of inhaled corticosteroids (ICS) with leukotriene receptor antagonists (LTRA) or long-acting beta-2 agonists (LABA), or were prescribed theophylline or biologics.

Cat exposure is not associated with increased asthma severity in children

From an initial cohort of 32,010 children with persistent asthma and allergy, 1,733 were excluded due to migration, death, or missing parental data. The resulting study population comprised 30,277 children, with a median age of 9.5 years; 38.6% were female, and 9.4% were exposed to cats.

Compared with the non-exposed group, the cat-exposed group had a higher proportion of females, similar initial asthma severity, and comparable parental history of asthma or allergy. Severe allergic rhinitis was less frequent in the cat-exposed group, at 11.5%, compared to 14.2% in the non-exposed group.

Asthma exacerbations occurred in 3.3% of the cat-exposed group versus 3.5% of the non-exposed group. Moderate-to-severe asthma affected 9.6% of the cat-exposed group and 10.1% of the non-exposed group. Cat exposure was not significantly associated with asthma-related endpoints, and there was no effect modification by age or sex.

In a subset of 1,428 children with both ACT and FEV1 data, including 97 who were cat-exposed, this group was older and had more severe baseline asthma and allergic rhinitis than the overall cohort. Uncontrolled asthma was reported in 22.3% of the non-exposed group and 16.5% of the cat-exposed group, but this difference was not statistically significant. ACT and FEV1 z-score distributions, mean FEV1 z-scores, and FEV1/FVC ratios were comparable between groups, indicating that cat exposure did not influence lung function or airway limitation.

Within the cat-exposed group, asthma outcomes were not influenced by the number of cats, their sex, or age. Excluding children with dog exposure resulted in similar null findings. Bias analysis for possible exposure misclassification yielded inconclusive results, as the adjusted odds ratios ranged above and below 1 across all scenarios.

The researchers noted that cat exposure may have been under-recorded because the Swedish National Cat Register was established only recently, potentially resulting in some cat-owning households being classified as unexposed.

Cat ownership was not linked to worse childhood asthma outcomes

Children with asthma and allergy showed no association between cat exposure and asthma exacerbations, severity, lung function, or asthma control. These findings suggest that cat exposure may not adversely affect asthma outcomes in this population. This information can help families and clinicians make informed decisions about pet ownership for children with asthma and allergies.

However, several limitations should be considered. The study lacked data on allergen-specific IgE sensitization, patterns of mono- versus polysensitization, prior cat ownership, duration of ownership, and whether cats were kept primarily indoors or outdoors. These factors may influence asthma severity and could not be evaluated in the current analysis.

The authors also cautioned that these findings apply specifically to children with established asthma and airway allergy and should not be generalized to non-allergic asthma. Differences in pet-keeping practices, climate, and environmental exposures may also limit the applicability of the findings to other countries and populations.

Importantly, the researchers noted that the absence of an association in cats should not be assumed to hold for all furry animals, as previous studies have reported different relationships between dog exposure and asthma outcomes.

Download your PDF copy by clicking here.