Pet Ownership Linked to Higher Risk of Childhood-Onset Asthma

Owning a cat or a dog puts children at higher risk for developing childhood-onset asthma, according to results from a recent metanalysis and systematic review.

Xiaoyi Ji, of the Children’s Hospital of Soochow University and the Jiaxing Maternal and Child Health Hospital, and colleagues conducted the study. The results were published in Frontiers in Pediatrics.

Investigators used 60 studies with large sample sizes that encompassed 27 countries and 1 871 295 children to conduct the metanalysis and systematic review.

Pet ownership was significantly associated with the risk of childhood-onset asthma (odds ratio [OR], 1.14; 95% CI, 1.08-1.21; heterogeneity index [I²]=79.1%) and with severe childhood asthma (OR, 1.15; 95% CI, 1.11-1.20; I²=67.9%).

Cat ownership is significantly related to the occurrence of childhood asthma (OR, 1.18; 95% CI, 1.05-1.33; I²=75.4%), as is dog ownership (OR, 1.12; 95% CI, 1.00-1.24; I²=79.6%).

However, “other furry pet” ownership was not associated with the occurrence of childhood asthma (OR, 1.03; 95% CI, 0.82-1.30; I²=54.9%).

Limitations of the study included the lack of available information to analyze the relationship between pet ownership and childhood asthma by age group, the lack of detailed information on the types of pets, and the lack of available data to quantify and compare the asthma risk for children who have pets that are not cats or dogs.

The mechanism underlying the association between pet ownership and childhood asthma risk “remains unclear,” the researchers wrote, referencing previous research that suggests protein secretions from cats and dogs may enhance innate immune signaling and promote airway hypersensitivity in patients with asthma. Pets also can be sources of household endotoxins, which may be associated with asthma.

“We found that pet ownership, especially cats and dogs, was positively correlated with the occurrence of childhood asthma,” the authors concluded. “Pet ownership was also positively correlated with the occurrence of severe childhood asthma. . . . When raising pets, it is better to choose those with less impact on the occurrence of childhood asthma. Furthermore, the contact of pets with infants should be avoided.”

Ji X, Yao Y, Zheng P, Hao C. The relationship of domestic pet ownership with the risk of childhood asthma: a systematic review and meta-analysis. Front Pediatr. 2022. doi:10.3389/fped.2022.953330