SAN FRANCISCO – Children diagnosed with atopic dermatitis when they were 1 year old were significantly more likely to have active food allergies and to have those allergies persist throughout childhood to age 18 years, based on findings from a prospective, longitudinal study of 287 Wisconsin children.
Mitchel L. Zoler/MDedge News
Dr. Anne Marie Singh
The link between atopic dermatitis (AD) and food allergy was especially strong in children who displayed early and recurrent AD; the link was weaker or essentially nonexistent for children with early transient AD or AD that first appeared later in childhood, Anne Marie Singh, MD, said while presenting a poster at the annual meeting of the American Academy of Allergy, Asthma, and Immunology.
The results also showed that even mild AD linked with an increased prevalence of food allergy when it appeared early and persisted, but more severe AD with this onset and recurrence pattern led to an even greater prevalence of food allergy, said Dr. Singh, a pediatric allergist and asthma specialist at the University of Wisconsin–Madison.
“The data suggest that something about early, recurrent AD increases the risk for food allergy throughout childhood,” Dr. Singh said in an interview. The findings suggest that surveillance for food allergies need to be intensified in infants who present with AD by the time they’re 1 year old and that food allergy surveillance should continue as these children age as long as their AD recurs.
The results also hint that these children might potentially benefit from steps aimed at desensitizing the allergy, although this must be proven in a future intervention study, she said.
The results suggest that a food allergy prevention regimen like the one used in the Learning Early About Peanut Allergy (LEAP) trial (New Engl J Med. 2015 Feb 26;372[9]:803-13) to prevent peanut allergy may be appropriate for selected, high-risk children with early AD, but this hypothesis needs testing, Dr. Singh said. She noted that some important differences exist between the patients enrolled in LEAP and the children studied in the current report: In LEAP, all enrolled children had severe eczema, an established egg allergy, or both. The findings reported by Dr. Singh came from children with AD, but only about 30% had moderate or severe eczema, and her analysis did not subdivide the observed food allergies by the type of food that caused a reaction.
She and her associates used data collected in the Childhood Origins of Asthma (COAST) study, begun in 1998, which enrolled 287 infants prior to birth who had at least one parent who was allergic, asthmatic, or both (Pediatr Allergy Immunol. 2002 Dec;13[s15]:38-43). The data showed that 62% of the infants had either no AD or transient AD, 14% had late onset AD, and 24% had early, recurrent AD. Although the data showed a statistically significant link between AD at 1 year old and food allergies throughout childhood, further analysis that broke the population into three different patterns of AD showed that the link with food allergy primarily existed among children with the early, recurrent form. Children with early, recurrent atopic dermatitis had a food allergy prevalence of 12%-27% annually through the age of 18 years.
“The data suggest that immunologic changes early in life are critical to food allergy development and that these changes have long-lasting effects throughout childhood,” Dr. Singh concluded. “The immunologic mechanisms by which early AD affects food allergy development and disease expression require further investigation.”
COAST received no commercial funding. Dr. Singh reported no relevant financial disclosures.
SOURCE: Singh AM et al. J Allergy Clin Immunol. 2019 Feb;143[2]:AB125.