LEAPing through the looking glass: secondary analysis of the effect of skin test size and age of introduction on peanut tolerance after early peanut introduction

Allergy. 2017 Aug;72(8):1254-1260. doi: 10.1111/all.13100. Epub 2017 Mar 22.


Background: In the Learning Early About Peanut Allergy (LEAP) study, early peanut introduction in high-risk 4- to 11-month-olds was associated with a significantly decreased risk of developing peanut allergy. However, the influences of key baseline high-risk factors on peanut tolerance are poorly understood.

Methods: Secondary analysis was conducted on the publically available LEAP dataset, exploring relationships between peanut tolerance, baseline peanut/egg sensitization, eczema severity/duration, age of introduction, gender, and race.

Results: A multiple logistic regression model predicting odds of successful oral food challenge (OFC) at 60 months noted higher odds with early introduction (OR 9.2, P < 0.001, 95% CI 4.2-20.3), white race (OR 2.1, P = 0.04, 95% CI 1.1-3.9), and advancing age (OR 4.8, P = 0.04, 95% CI 1.1-20.8). Odds of peanut tolerance were lower with increasing peanut wheal size (OR 0.58, P < 0.001, 95% CI 0.46-0.74), increased baseline SCORAD score (OR 0.98, P = 0.04, 95% CI 0.97-1), and increased kUA /l of egg serum IgE (sIgE) (OR 0.99, P = 0.04, 95% CI 0.98-1). The probability of peanut tolerance in the early introduction group was 83% vs 43% in the avoidance group with SPT wheal of <4 mm. The probability of a successful OFC was significantly higher with peanut introduction between 6 and 11 months than at 4-6 months. Increasing eczema severity had limited impact on the probability of peanut tolerance in the early introduction arm.

Conclusion: Increasing peanut wheal size predicted peanut tolerance only in the avoidance arm. Peanut introduction between 6 and 11 months of age was associated with the highest rates of peanut tolerance, questioning the 'urgency' of introduction before 6 months.

Keywords: Learning Early about Peanut; allergy prevention; complementary feeding; early peanut introduction; peanut allergy.

MeSH terms

  • Age Factors
  • Allergens / administration & dosage
  • Allergens / immunology*
  • Arachis / immunology*
  • Eczema / diagnosis
  • Eczema / epidemiology
  • Eczema / immunology
  • Female
  • Humans
  • Immune Tolerance*
  • Immunization
  • Immunoglobulin E / blood
  • Immunoglobulin E / immunology
  • Male
  • Peanut Hypersensitivity / diagnosis
  • Peanut Hypersensitivity / epidemiology*
  • Peanut Hypersensitivity / immunology*
  • Peanut Hypersensitivity / prevention & control
  • Population Surveillance
  • Probability
  • Risk Factors
  • Skin Tests


  • Allergens
  • Immunoglobulin E