Early life food allergy a red flag for later asthma, lung problems

Food allergy in infancy, regardless of whether it resolves, may affect lung development and contribute to poorer respiratory outcomes such as asthma and reduced lung function in childhood, as shown in a study.

Data from health assessments showed that food allergy, but not food-sensitized tolerance, at age 1 year was associated with lung function deficits, as reflected by reduced forced expiratory volume (FEV1; –0.19, 95 percent confidence interval [CI], –0.32 to –0.06) and forced vital capacity (FVC; –0.17, 95 percent CI, –0.31 to –0.04), at age 6 years. [Lancet Child Adolesc Health 2023;doi:10.1016/S2352-4642(23)00133-5]

When it comes to specific food allergies, transient egg allergy and transient peanut allergy were associated with reduced FEV1 and FVC when compared with never having the allergy. Persistent egg allergy and late-onset peanut allergy were also associated with lung function deficits, but to a lesser extent.

Meanwhile, both food-sensitized tolerance and food allergy at age 1 year were associated with greater odds of having asthma at age 6 years (adjusted odds ratio [aOR], 1.97, 95 percent CI, 1.23–3.15 and aOR, 3.69, 95 percent CI, 2.81–4.85, respectively). Participants with persistent and late-onset peanut allergy as infants had three- to fivefold greater odds of having asthma in childhood (aOR, 3.87, 95 percent CI, 2.39–6.26 and aOR, 5.06, 95 percent CI, 2.15–11.90, respectively).

Lead study author Dr Rachel Peters from the Murdoch Children’s Research Institute in Melbourne, Victoria, Australia, expressed concern regarding the association between early life food allergy and poor respiratory outcomes at age 6 years, given that reduced lung growth in childhood could lead to further health problems in adulthood including respiratory and heart conditions.

Lungs grow and develop as children grow and gain weight, Peters noted. Children with food allergies are often shorter and lighter may have smaller lungs than their peers. This could be one reason why food allergies are linked to reduced lung function.

“The growth of infants with food allergy should be monitored. We encourage children who are avoiding foods because of their allergy to be under the care of a dietician so that nutrition can be catered for to ensure healthy growth,” Peters said.

The findings of the present study should help clinicians tailor patient care and encourage greater vigilance around monitoring respiratory health, added senior study author Prof Shyamali Dharmage from Murdoch Children’s Research Institute.

Dharmage also stressed the importance of being vigilant for asthma symptoms in children with food allergy, because poorly controlled asthma is considered a risk factor for severe food-induced allergic reactions and anaphylaxis.

For the study, Peters and Dharmage, along with their colleagues, used data from the longitudinal, population-based HealthNuts cohort study and recruited 5,276 one-year-olds who attended immunization sessions. At age 1 year, all children completed skin prick testing to four food allergens and an oral food challenge.

Out of those who were recruited, 3,233 children completed the health assessment (skin prick testing for ten foods and eight aeroallergens, oral food challenges, and lung function testing by spirometry) at age 6 years and were included in the analysis. A total of 430 children (13.7 percent) received a diagnosis of asthma by their sixth year of life.

The next step in the study, according to the researchers, is to examine whether interventions to prevent food allergy would have a positive impact on respiratory health.