A monumental new analysis quantifies risk factors such as allergen and antibiotic exposure, other allergic conditions and more.
Leaving peanut introduction until after 12 months of age was associated with 155% higher odds of developing food allergy, according to US research.
A new meta-analysis, published in JAMA Pediatrics, identified and quantified predictive factors for early life food allergy. The researchers used data from 2.8 million participants, spanning 190 studies and 40 countries.
Prior allergic conditions were the strongest and most certain factors associated with early life food allergy. Atopic dermatitis (AD) was the best example of this, both in the first year (OR 3.88) and in the first three years of life (OR 3.34).
When stratified by disease severity, more severe AD was associated with increased odds of food allergy compared with mild-to-moderate disease (OR 1.22).
Allergic rhinitis was associated with 239% increased odds of developing food allergy, and wheeze more than doubled the odds (OR 2.11).
Other strong associations included increased transepidermal water loss (OR 3.36) and filaggrin gene loss-of-function sequence variation (OR 1.93).
One of the highest associations was with parental migration before birth, which increased the odds of developing early life food allergy by 228%.
Antibiotic exposure was also clearly associated with the development of food allergies, with exposure in the first month of life showing 311% higher odds, while exposure in utero and during the first year of life had ORs of 1.32 and 1.39, respectively.
Related
In terms of delayed allergen exposure, associations were found with peanut (OR 2.55), fish (OR 1.53), egg (OR 1.44) and fruit introduction (OR 1.68) after 12 months of age.
A family history of allergies, not limited to food allergies, was also strongly associated with early life food allergy in children. Maternal allergy appeared more predictive than paternal allergy (OR 1.98 vs OR 1.69), but sibling allergy was the strongest family history association, increasing the odds by 136%.
Both parents having food allergies equated to 107% higher odds of a child developing early life food allergy.
Being male at birth, the firstborn child or delivery by caesarean section also increased the odds (OR 1.24, OR 1.13 and OR 1.16, respectively).
Factors such as low birth weight, post-term birth, partial breastfeeding, maternal intake of fish or cheese during pregnancy, maternal stress and high household income showed no significant risk difference.
The overall incidence of food allergy across challenge studies was around 5%.
The review was the first to contextualise this many risk factors, rather than focusing on isolated exposures, authors explained.
“By systematically quantifying and classifying both major and minor predictors, this study reconciles inconsistencies in definitions of at-risk populations for developing food allergy in clinical guidelines and trials, advances the concept that the development of food allergy is multifactorial rather than solely driven by eczema or timing of allergen introduction, and provides systematically appraised evidence directly responsive to the patient,” they wrote.
