Timing of allergenic food introduction and risk of IgE-mediated food allergy: systematic review and meta-analysis

Scarpone, Roberta; Kimkool, Parisut; Ierodiakonou, Despo; Leonardi-Bee, Jo; Garcia-Larsen, Vanessa; Perkin, Michael; Boyle, Robert J

Abstract

Importance: Earlier egg and peanut introduction probably reduce risk of egg or peanut allergy, but it is uncertain whether food allergy as a whole can be prevented using earlier allergenic food introduction.

Objective: This study is a systematic review on timing of allergenic food introduction to the infant diet and risk of food allergy.

Data Sources: Medline, Embase and CENTRAL were searched to December 2022.

Study Selection: Randomized controlled trials evaluating timing of allergenic food introduction during infancy were included.

Data Extraction and Synthesis: Data were extracted in duplicate and synthesized using a random-effects model. GRADE was used to assess certainty of evidence.

Main Outcomes and Measures: Primary outcomes were risk of allergy to any food and withdrawal from the intervention. Secondary outcomes included allergy to specific foods.

Results: Of 9283 titles screened, data were extracted from 23 eligible trials (56 reports, 13749 randomized participants). There was moderate-certainty evidence from 4 trials (3295 participants) that earlier introduction of multiple allergenic foods at 2 to 12 months (median 3 to 4 months) was associated with reduced food allergy (risk ratio [RR], 0.49; 95% CI, 0.33-0.74; I2=49%). Absolute risk reduction for a population with 5% incidence of food allergy was 26 cases (95% CI, 13-34 cases) per 1000 population. There was moderate-certainty evidence from 5 trials (4703 participants) that earlier introduction of multiple allergenic foods at 2 to 12 months was associated with increased withdrawal from the intervention ([RR], 2.29; 95% CI, 1.45-3.63; I2=89%). Absolute risk difference for a population with 20% withdrawal from the intervention was 258 cases (95% CI, 90-526 cases) per 1000 population. There was high-certainty evidence from 9 trials (4811 participants) that earlier introduction of egg at 3 to 6 months was associated with reduced egg allergy (RR, 0.60; 95% CI, 0.46-0.77; I2=0%); and high-certainty evidence from 4 trials (3796 participants) that earlier introduction of peanut at 3 to 10 months was associated with reduced peanut allergy (RR, 0.31; 95% CI, 0.19-0.51; I2=21%). Evidence for timing of introduction of cow's milk and risk of milk allergy was very low certainty.

Conclusions and Relevance: Earlier introduction of multiple allergenic foods was associated with lower risk of developing food allergy, but a high rate of withdrawal from the intervention.

Citation

Scarpone, R., Kimkool, P., Ierodiakonou, D., Leonardi-Bee, J., Garcia-Larsen, V., Perkin, M., & Boyle, R. J. (in press). Timing of allergenic food introduction and risk of IgE-mediated food allergy: systematic review and meta-analysis. JAMA Pediatrics,

• Journal Article Type: Article
• Acceptance Date: Jan 18, 2023
• Deposit Date: Jan 25, 2023
• Print ISSN: 2168-6203
• Electronic ISSN: 2168-6211
• Publisher: American Medical Association
• Peer Reviewed: Peer Reviewed
• Public URL: https://nottingham-repository.worktribe.com/output/16499675