Most people with peanut allergy in U.S. are adults, but kids remain the focus

Feb. 9 (UPI) -- Nearly 3% of adults in the United States, or 4.5 million people, are allergic to peanuts, according to a study published Tuesday by the Journal of Allergy and Clinical Immunology.

Even though roughly 75% of people in the country with a peanut allergy are over age 17, it is often considered more of a health problem for children, said to Dr. Ruchi Gupta, co-author of the study.

Approximately one in six U.S. adults with a peanut allergy developed it at age 18 or older, and up to one-fifth of adults with the allergy report visiting a hospital emergency room for food allergy treatment annually, study data showed.

"Given the high prevalence of peanut allergy among U.S. adults, additional therapies are needed to help address this growing burden of disease," said Gupta, a professor of pediatrics at Northwestern University Feinberg School of Medicine and a physician at Ann & Robert H. Lurie Children's Hospital in Chicago.

Earlier this year, the U.S. Food and Drug Administration approved a peanut allergy therapy for children age 4 to 17, but no FDA-approved therapies exist for those with adult-onset food allergy.

In addition, people who developed their peanut allergy during adulthood are less likely to report having an epinephrine auto-injector, or "epi-pen," prescription -- a rescue medication for those who go into anaphylactic shock during an allergic reaction -- than those who developed their peanut allergy during childhood.

For this study, the researchers conducted a telephone- and web-based survey of more than 40,000 U.S. adults. They asked for detailed information about any suspected food allergies, including specific allergic-reaction symptoms and details about clinical diagnosis of food allergies, as well as demographic information.

Among respondents, 2.9% reported a current peanut allergy and 1.8% had a physician-diagnosed peanut allergy or a history of peanut-allergic reaction symptoms.

In addition, two in three adults with a peanut allergy have at least one other food allergy, most commonly to tree nuts, but more than one in five also are allergic to shellfish.

Many people who report peanut allergies and experience potentially severe allergic reactions are not obtaining a clinical diagnosis of their allergies, according to the researchers.

"Unlike allergies such as milk or egg, which often develop early in life and are outgrown by adolescence, peanut allergy appears to affect children and adults to a similar degree," study co-author Christopher Warren said.

"Our study shows many adults are not outgrowing their childhood peanut allergies, and many adults are developing peanut allergies for the first time," said Warren, director of population health at Northwestern University Feinberg School of Medicine.