Early life food allergy has been linked to childhood asthma and reduced lung function, but researchers warn against unnecessary testing.
Melbourne research presented at the recent ASCIA 2023 Conference in Sydney has provided evidence that food allergy in infancy is associated with reduced lung function in six-year-olds.
Data from the population-based longitudinal HealthNuts study has also revealed that food allergy and food sensitisation were linked with an increased risk of asthma in childhood. The effect was greater for allergy than sensitisation, and for persistent and late-onset allergy than transient allergy.
“We’d like clinicians to be aware of these risks and hope that this helps to direct greater vigilance towards monitoring respiratory health in children who have food allergies, and monitoring children with food allergy for the development of asthma,” Associate Professor Rachel Peters of the Murdoch Children’s Research Institute told conference delegates.
“Ensuring that appropriate management strategies are in place is important both for the management of asthma, but also because poorly controlled asthma may be associated with a higher risk of anaphylaxis,” said Professor Peters.
The first-of-its-kind study, published in Lancet Child & Adolescent Health, involved over 5000 one-year-olds who underwent skin prick testing to common food allergens. Those who had a detectable wheal were invited to complete oral food challenges to test for food allergy.
At six years of age, over 3000 participants completed further food and aeroallergen tests, as well as lung function testing by spirometry.
One of the key findings for lung function was that food allergy was associated with restrictive rather than obstructive lung function patterns. These patterns were not mediated by the presence of asthma, suggesting an independent pathway from food allergy to impaired lung function.
“This is concerning because there’s new evidence that restrictive lung function trajectories in childhood are associated with multiple adult cardiometabolic outcomes, including obesity, diabetes and cardiovascular conditions,” said Professor Peters.
She said that further research was needed to understand the mechanisms involved, but one potential mechanism may be impaired lung development in line with lighter body weight and shorter height in children with allergies.
“We would recommend that children who have a food allergy and are on restricted diets should consider seeing a dietitian to ensure that their diet is being optimally managed to support healthy growth,” Professor Peters told delegates.
Professor Peters finished on a cautionary note, warning not to test for food sensitisation without good reason.
“Although we found that food sensitisation without clinical allergy was associated with a modest increase in the risk of asthma or poor lung function, we would just like to caution against screening infants for food sensitisation in the absence of a strong suspicion of food allergy, because it could lead to unnecessary allergen avoidance, thereby increasing the risk of food allergy,” she said.
The team is conducting further research to see if the lung function patterns persist into adolescence, with measures of lung function at 10 and 15 years of age.