Food allergy appears in adulthood too, not only in childhood
Nearly half of food allergies observed in adults started appearing in adulthood, in contrast to common belief that most food allergies started in childhood, according to a US population-based survey presented at the ACAAI Annual Meeting 2017 in Boston, Massachusetts, US.
“Food allergies are often seen as a condition that begins in childhood, so the idea that 45 percent of adults with food allergies develop them in adulthood is surprising,” said lead author Dr Ruchi Gupta of Ann & Robert H. Lurie Children's Hospital of Chicago in Chicago, Illinois, US.
Among the adults with food allergy, 45 percent reported at least one adult-onset food allergy. The most common food allergy reported is shellfish, with an estimated prevalence of 3.69 percent (95 percent confidence interval [CI], 3.48–3.91). This was followed by allergy to peanut (estimated prevalence, 2.66 percent) and to tree nut (estimated prevalence, 2.66 percent). [ACAAI 2017, abstract OR077]
More than half of the allergic reactions to specific food were severe, defined as involvement of two or more organ systems in the reaction ─ with 68.33 percent of patients who were allergic to peanut, 58.29 percent to any tree nut, 58.14 percent to any shellfish, and 56.62 percent to fin fish reporting at least one severe allergic reaction.
“Our research also found that, among black, Asian, and Hispanic adults, the risk of developing a food allergy to certain foods is higher than for whites, specifically for shellfish and peanuts [p<0.05],” said study co-author Christopher Warren of The Northwestern University Feinberg School of Medicine in Chicago.
“For example, Asian adults were 2.1 times more likely to report a shellfish allergy than white adults, and Hispanic adults reported a peanut allergy at 2.3 times the frequency of white adults,” he observed.
In addition, age also appeared to be predictive for the risk of developing specific food allergy in adulthood. Compared with adults aged 18–29 years, those aged 30–39 years were more likely to develop allergy to shellfish (p<0.05), while older persons aged 60 years and above were less likely to develop specific allergies to all food categories tested, including shellfish, fin fish, peanut, tree nut, and sesame (all p<0.05).
“Because many adults believe food allergies mostly affect children, they may not think to get tested. It is important to see an allergist for testing and diagnosis if you are having a reaction to a food and suspect a food allergy,” advised Warren, noting that people might overlook a food allergy reaction as a food intolerance.
The population-based study surveyed 53,575 adults in the US through a dual-sampling approach, using weighting methods to calculate estimated prevalence and multiple regression models for adjusted odds ratio.