First population-based food allergy study explores racial and ethnic differences in all age groups

Food allergy has not been on the radar of most racial and ethnic communities. But a new Northwestern Medicine study -; the first population-based food allergy study in the U.S. to explore racial and ethnic differences in all age groups -; shows why it should be.

The new study found the prevalence of food allergy is highest among Hispanic, non-Hispanic Black and Asian individuals across all ages. And food allergy is lowest among households earning more than $150,000 a year.

The study will be published June 14 in JAMA Open Network.

There has been a paucity of population-based data of food allergy among racial and ethnic groups in the U.S., the authors said. Most previous studies also focused on children.

Food allergies are not frequently talked about impacting racial and ethnic communities. It's not on the radar. But we now know it does impact them more, and it's important to improve awareness.

It is also critical to improve access to diagnosis and treatments for food allergy. It is an exciting time with new treatments, and making sure they reach racial and ethnic minorities who have higher rates of food allergy is essential."

Dr. Ruchi Gupta, study corresponding author

Gupta is director of the Center for Food Allergy and Asthma Research and a professor of pediatrics at Northwestern University Feinberg School of Medicine. She also is a physician at the Ann & Robert H. Lurie Children's Hospital of Chicago.

New treatments include various forms of immunotherapy including oral, epicutaneous (on the skin) and sublingual (under the tongue), all of which desensitize the immune system to the allergen. Another treatment is new biologics, Gupta said, which block the allergic reaction cascade.

When Gupta first began doing food-allergy research two decades ago, researchers did not know disparities existed.

"We now know that racial and ethnic minorities as well as underserved populations often do not get to an allergist for diagnosis," Gupta said. "They have the symptoms of food allergy but the access to get to a specialist has been challenging, and the fact that there were no treatments led them to just try and avoid the food."

But the new study shows that food allergy -; which affects 11% of adults and 8% of children in the U.S.-; touches adults and children of every race and ethnicity.

Among the study findings:

• Prevalence of food allergy is highest among Asian (10.5%), Hispanic (10.6%) and non-Hispanic Black individuals across all ages (10.6%).
• Non-Hispanic Black individuals with food allergy were most likely to report food allergy to multiple foods (50.6%).
• Asian and non-Hispanic white individuals had the lowest rates of severe food allergy reactions.
• Prevalence of food allergy was lowest within households earning more than $150,000 per year (8.3%).

In addition to prevalence of food allergy, this study also reports on outcomes such as common food allergens, emergency department visits for food-allergic reactions and epinephrine usage. It also factors in socioeconomic status, which is related to food-allergy prevalence.

The study also suggests that an ensemble of allergic conditions all have similar patterns in terms of whom is affected. The ensemble is part of a progression of allergic conditions that develop over infancy and into childhood (called the atopic march) including eczema, food allergy, allergic rhinitis and asthma.

"There haven't been enough genetic changes over the last 30 to 40 years to explain this grouping of allergic conditions," said study co-author Christopher Warren, an epidemiologist and an assistant professor of preventive medicine at Northwestern University Feinberg School of Medicine. "Clearly, something has changed in the environment. It behooves us to figure out what are those changes, and how can we reverse them or add interventions to mitigate them."

"It Is an exciting time in food allergy with new diagnostics, prevention and treatments," Gupta said. "Our goal is to see these numbers start to come down in the next 30 to 40 years."

In the study, a population-based survey was administered online and via telephone to a nationally representative sample of the U.S. population. More than 50,000 households were surveyed, comprising responses for nearly 80,000 individuals.

Northwestern is hosting a Global Food Allergy Prevention Summit July 7-9 in Chicago. Some of the sessions will cover food allergy disparities.

Other Northwestern authors include first author Jialing Jiang and Dr. Audrey Brewer.

The study was funded in part by grant R21AI135702 from National Institute of Allergy and Infectious Disease of the National Institutes of Health.