Amino acid formula as a new strategy for diagnosing cow´s milk allergy in infants: is it cost-effective?

To estimate the cost-effectiveness of a new strategy that uses an amino acid formula in the elimination diet of infants with suspected cow's milk allergy (CMA). This pharmacoeconomic study was developed from the perspective of the Brazilian Public Healthcare System. The new strategy proposes using an amino acid formula in the diagnostic elimination diet of infants (≤ 24 months) with suspected CMA. Our rationale is that infants who do not respond to the amino acid formula do not suffer from CMA. Patients with a positive oral challenge test receive a therapeutic elimination diet based on Brazilian Food Allergy Guidelines. This approach was compared to the current recommendations of the Brazilian Food Allergy Guidelines. A decision model was constructed using TreeAge Pro 2012 software. Model inputs were based on a literature review and the opinions of a panel of experts. A univariate sensitivity analysis of incremental cost-effectiveness ratios was performed. The mean cost per patient of the new amino acid formula strategy was R$3,341.57, while the cost of the current Brazilian guidelines strategy was R$3,641.08. The mean number of symptom-free days per patient, which was used as an indicator of effectiveness, was 900.6 and 875.7 days, respectively. The new strategy is therefore dominant. In the sensitivity analysis, the dominance was maintained with parameter variation. This analysis did not evaluate the impact of the new strategy on quality of life or whether it improved the general well-being of infants with CMA or their parents. The new strategy, which uses an amino acid formula in the elimination diagnostic diet followed by an oral food challenge, is a dominant pharmacoeconomic approach that has a lower cost and results in an increased number of symptom-free days.