Researchers found that dog ownership among children with dog allergies may reduce the risk of developing eczema by age 4 years, whereas cat ownership may increase the risk among children with cat allergies. These are the results of a new study published in the Journal Pediatrics that examines the relationship between pet ownership and eczema.
Eczema, a chronic condition that results in dry, irritated and itching skin, occurs most commonly during childhood, but can persist into adulthood. Children with a family history of eczema, asthma or allergies are at greater risk of developing eczema.
The study author, Tolly Epstein, M.D. stated that “the number of children with allergic eczema is rising, but the reasons for this are unclear. Our research suggests that exposure to dog allergens early in life may actually have a protective effect against developing future allergies among a high-risk population.”
The study, “Opposing Effects of Cat and Dog Ownership and Allergic Sensitization on Eczema in an Atopic Birth Cohort”, showed that children who have lived with a dog since before age 1 and test positive for dog allergy on a skin prick test have a significantly lower risk of developing eczema than children who tested positive but didn’t live with a dog.
The key points of the study were that:
- Early dog ownership may reduce the risk of developing eczema associated with dog sensitization, while cat ownership may increase the risk of developing eczema among cat-sensitized children.
- Early dog ownership also appeared to be protective from the development of cat allergies, suggesting that dog ownership may have positive immunogenic effects.
Of the 636 children who completed the study, 184 had a dog in the home before age 1, while 121 had a cat. A child’s positive test for dog allergy on an skin prick test was associated with an increased risk of eczema in dogless homes when compared against eczema risk for kids with dogs. Of those from homes without dogs who tested positive for dog allergy on the skin prick test, 30% developed eczema, while only 15% of children who tested negative for the allergy in a dogless home developed eczema.
Children of cat owners fared worse, as 54% of children who tested positive for cat allergy developed eczema, while only 11% of those who tested negative also had eczema.
The researchers found their study supported previous research that showed dog ownership provided a significant, 4-fold protective effect against eczema at four years when compared with households without dogs. They also noted children of cat owners were 13 times more likely to develop the skin condition than children of households without cats.