Immediate introduction to baked milk accelerates tolerance in cow’s milk-allergic infants

Baked milk can be introduced safely and effectively into the diets of young children diagnosed with cow’s milk protein allergy as part of the Milk Allergy in Primary Care, or MAP, milk ladder, according to a study published in Allergy.

Also, a supervised single dose at diagnosis may accelerate progression up the MAP milk ladder — which introduces children to food with amounts of milk that increase step by step — as parents develop the confidence to proceed, Yvonne M. d’Art, MB, MSc, clinical research fellow at National Children’s Research Centre, and colleagues wrote.

The researchers recruited 60 infants (mean age, 7.5 months; standard deviation, 2.1; 40 boys) with cow’s milk protein allergies from three health care centers in Ireland, with 57 followed for 6 months, 55 followed for 12 months, and two whose parents reported milk ladder position by phone at 12 months.

The parents of these infants were instructed in using MAP. Step 1 includes cakes, cookies and other extensively baked foods. Subsequent steps include foods with less extensively cooked milk, then yogurts and cheese before whole milk is introduced at step 12. Infants must be able to tolerate a normal age-related portion of each food at least three times in a single week before moving to the next step.

Researchers randomly assigned the children 2:1 into intervention (n = 40) and control (n = 20) groups. The intervention group immediately received a supervised single 0.5 mg dose of milk protein and then followed the MAP ladder at home. The control group received routine care for their cow’s milk protein allergy before implementing the MAP ladder at home.

Infants had been diagnosed with IgE-mediated cow’s milk protein allergy via their history of reactions to milk products and by a positive skin prick test, which was repeated 6 and 12 months after randomization. Blood tests were conducted at enrollment and 6 months later as well.

At 6 months, a greater proportion of infants in the intervention group reached step 6 or higher on the ladder (73% vs. 50%; P = .048) or step 12 on the ladder (30% vs. 10%; P = .049) compared with the control group.

At 12 months, a greater proportion of the intervention group reached step 6 or higher (86% vs. 75%) or completed the ladder (65% vs. 35%; P = .03) compared with the control group.

The researchers found a significant association between smaller baseline SPT and reaching step 6 by 6 months (progressors, 5.7 mm vs. non-progressors, 6.7 mm), but not at 12 months. There was a significant association between lower baseline milk IgE and progress or nonprogress at 6 months as well (4.7 KU_A/L vs. 37.5 KU_A/L).

Further, there was a significant association between progress and changes in SPT. Progressors experienced a significantly larger decrease regardless of which treatment group they were in, although those in the treatment group saw a greater effect (treatment group, P = .0001; control group, P = .008).

The researchers also sought to evaluate the association between maternal anxiety with their child’s rate of tolerance acquisition to cow’s milk. Parents completed the EuroPrevall Food Allergy Quality of Life, the related parent form, the Food Allergy Independent Measure and the State and Trait Anxiety Inventory (STAI) questionnaires at 1, 3, 6 and 12 months after randomization.

The researchers defined state anxiety (S-anxiety) as psychological and physiological temporary reactions to adverse situations and trait anxiety (T-anxiety) as individual differences in the tendency to attend to, experience and report negative emotions.

Time had a statistically significant effect on S-anxiety scores (P = .002) but not on T-anxiety scores. The intervention group experienced a significant difference in S-anxiety scores between baseline and at 6 months (P = .008), but there was no significant difference for the control group between baseline.

Specifically, mothers of infants who responded to treatment saw significant improvements in their S-anxiety scores (P = .035) from baseline compared with mothers of infants who were not progressors.

There were significant associations between maternal STAI scores and changes in SPT between baseline and 6 months and baseline and 12 months as well, the researchers found, noting that all progressors had significant decreases in SPT.

According to the researchers, the single dose of milk administered at diagnosis improved and accelerated outcomes for MAP treatment, with inverse associations between progress on the ladder and levels of maternal anxiety.

In fact, the researchers suggested, parents who see safe and quick progress may feel confident to continue treatment, further improving outcomes. These results have implications for the future management of cow’s milk and other food allergies, the researchers added, particularly as maternal anxiety is considered as part of that treatment.