Climate Change May Not Increase Allergies in Kids With Asthma: Study

FRIDAY, Nov. 19, 2021 (HealthDay News) -- While climate change gets a lot of notice for its numerous negative impacts around the globe, children's allergies may not be among them.

Despite climate change, with the longer growing seasons and larger pollen loads that are attributed to it, more than 5,800 children in the Los Angeles area with asthma did not have an increase in allergic sensitization or allergy diagnosis over a 15-year period, a new study showed.

The findings were presented earlier this month at an annual meeting of the American College of Allergy, Asthma and Immunology.

"We were somewhat surprised at the results as we expected there would be an increase in the number of kids with asthma who were sensitized to pollen and other allergens," said principal investigator Dr. Kenny Kwong, a Los Angeles-based allergist.

"Between 80%-90% of children with asthma have allergy triggers, which is why it's important for children with asthma to be tested for allergies," he said in a meeting news release. "Allergy triggers can cause asthma flares in children."

When people's immune systems become sensitized to an allergen, those patients will likely develop symptoms of an allergy each time they are exposed to that same allergen, which for others is harmless.

"Although temperatures have been rising and pollen loads increasing, if someone is not genetically predisposed to allergies, they are not likely to be sensitized to more allergens," said allergist and study co-author Dr. Lyne Scott, an associate professor of pediatrics at USC's Keck School of Medicine.

"The growing season is year-round in L.A. and people with allergies who are already sensitized to pollens suffer more intensely when the growing season is longer, or the air quality isn't good," Scott said in the release. "It is important to remember that sensitization does not equate to severity so those with allergies may have worse symptoms."

The study followed 5,874 kids with asthma in Los Angeles for 15 years, who underwent more than 123,200 skin prick tests to dust mites, cats, dogs, cockroaches, tree pollen, grass pollen and weed pollen. All the patients had been diagnosed with asthma and allergic rhinitis by an asthma specialist using history, physical examination and spirometry when it was age-appropriate.

The researchers found no increase in allergic sensitization or allergy diagnosis among the children.

The findings were also published recently in the journal Annals of Allergy, Asthma and Immunology.

More information

The U.S. National Library of Medicine has more on seasonal allergies.

SOURCE: American College of Allergy, Asthma and Immunology, news release, Nov. 5, 2021