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.

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.