The economic effect and outcome of delaying oral food challenges

Food specific IgE (sIgE) is a useful marker to assess predictability of oral food challenge (OFC) outcome. A threshold of less than 2 kUA/L for peanut, egg, and milk has been proposed as a 50% negative predictive value at which patients may pass an OFC.

To assess the economic effect and outcome of delaying OFCs.

A retrospective analysis was performed for peanut, egg, and milk OFCs conducted between 2001 and 2012 at a tertiary food allergy referral center. Delayed OFC was defined as greater than 12 months from the time the sIgE level became less than 2 kUA/L. Time to OFC was explored in association with skin prick test result (wheal size), OFC outcome, and the economic effect of delay.

Of 319 challenges, 173 OFCs were delayed (54.2%) by a mean time of 35.5 months (range, 13-123 months) vs a mean time of 4.2 months in the 146 challenges that were not delayed (P < .001). The overall OFC passage rate was 89.9%. There was no association between delayed OFC and history of anaphylaxis, type of allergen, age at OFC, or challenge outcome. Delay in OFC was associated with an estimated mean economic cost of $12,203 per patient ($4,184 per 12 months) and $1,951,487 total (total delay, 5,597 months) in this population.

Despite a 50% negative predictive value, more than 50% of OFCs were delayed in this population by a mean time of nearly 3 years. Delaying OFC is associated with increased costs, and quality improvement is needed to help decrease time to OFC and reduce the economic burden of food allergy on families and the health care system.