Feeding whole goat milk-based formula to infants can reduce the incidence of atopic dermatitis (AD) in the first year of life, especially if there is a parental history of the skin condition, a multi-site, randomized clinical trial published in Clinical Nutrition has found.

Although whole goat milk formula did not reduce the incidence rate of AD as defined by United Kingdom Working Party (UKWP) criteria in healthy term infants when compared with cow milk formula, there was a 34% risk reduction in the participants in the per protocol population who had an AD diagnosis. In infants with a parental history of AD, the goat milk formula significantly reduced the risk of developing a clinical AD diagnosis by 64%.

Around 80% of AD (eczema) symptom onset occurs within the first year of life. A family history of AD increases the risk for AD in offspring by as much as three times, but nutrition or dietary elimination so far has had limited effect on development of the condition.

Evidence for an association between breastfeeding and a reduced risk for eczema in children up to 2 years of age is weak. While studies of hydrolyzed cow milk protein infant formulas have reported benefits for AD in children with a family history of the condition, a 2017 Cochrane review did not find conclusive evidence for a protective effect in healthy infants.

An Australian study, meanwhile, explored the suitability and safety profile of whole goat milk formula in infants, and found a promising, but not statistically significant, lower incidence of AD in whole goat milk formula compared with cow milk formula.

Picking up then where the Australian study left off, Berthold Koletzko, MD, PhD, of the Dr. von Hauner Children’s Hospital in Munich, Germany, and colleagues developed a two-arm, parallel, randomized, double-blind, controlled trial (NCT04599946) to study the effect of whole goat milk formula compared with cow milk formula in infant AD.

The investigators analyzed data from 2132 infants enrolled across six sites in Spain and four in Poland. The primary outcome measure was AD diagnosed by study investigators at three study visits using the UKWP diagnostic criteria. The intervention period began at recruitment and ended with the 12-month visit.

Infants were randomly assigned to whole goat milk formula (n = 1065) or cow milk formula (n = 1067). Nearly 13% (n = 268) of infants dropped out by age 12 months, with the majority discontinuing before the 4-month visit. In the goat milk group, 15% dropped out; 10% of the cow milk group did so (P < .001).

The primary analysis was performed in the intention-to-treat population. The per-protocol population comprised infants who met the compliance criteria and attended all face-to-face visits (4 and 6 months) up to 12 months of age, unless a previous AD diagnosis was made at the study site. Compliance criteria were no formula-feeding interruption exceeding 3 consecutive days and no introduction of solid foods before the age of 4 months.

Infants who consumed regular formula for more than 4 weeks before the study, had a clinical diagnosis of AD or any other skin condition that could confound the diagnosis of AD, or a cow milk intolerance or allergy were excluded.

The whole goat milk formula included goat milk fat (approximately 50% of total fat) with added vegetable oils, and a whey to casein ratio of 20:80. The cow milk formula was the standard based on skim cow milk and cow whey, with 5% milk fat and 95% of fat from added vegetable oils, with a whey to casein ratio of 60:40. Infant formulas were fed until 6 months of age, then, in line with usual practice in Europe, additional formula was offered.

“Both formulas used in this study contain major milk allergens, notably the whey proteins β-lactoglobulin and α-lactalbumin,” Koletzko and colleagues wrote. The whey protein content is lower in goat milk, as whey contributes only 20% to total protein compared to 60% in cow milk formula. Also, the alpha-S1-casein content is lower in whole goat milk formula compared to cow milk formula, resulting in the formation of a softer curd, they noted. “In vitro experiments indicate this softer curd to be associated with enhanced hydrolysis of milk proteins during simulated gastric digestion.”

After a UKWP AD diagnosis was made, the severity of AD was rated using Patient-Oriented Eczema Measure and SCORing Atopic Dermatitis measures. The highest ever recorded score for each participant was used.

The investigators found that 192 infants met the UKWP criteria at the study sites, whereas 245 infants were diagnosed by a doctor during the study period. The cumulative incidence rate of AD diagnosed by investigators for both groups was 11.6 per 100 person-years without any difference between the goat milk formula and the cow milk formula groups (incidence rate ratio [IRR], 1.00; 95% CI, 0.75-1.32; P = .991).

In the per-protocol population, the incidence of doctor-diagnosed AD was lower in the goat milk group compared with the cow milk group (IRR, 0.66; 95% CI, 0.49-0.9; P = .008). In infants with a parental history of AD, the protective effect of goat milk formula was stronger, with an IRR of 0.36 (95% CI, 0.17-0.76; P = .007).

“The risk reduction of chronic eczema with whole goat milk formula is important, with a very large preventive effect particularly in infants with a positive family history,” Koletzko told Medscape Medical News. “Chronic eczema can induce serious burdens for the affected child and the whole family, with lasting itching, scratching, disturbed sleep, and mood changes.”

Commenting on the study, Cynthia Chen-Joea, DO, MPH, said, “What stood out to me most was the finding that eczema was diagnosed 64% lower in infants with a parental history of atopic dermatitis. That’s huge,” she said. “That’s the family sitting in my exam room, a mom or dad who has struggled with eczema their whole life and is now worried about their newborn.” For those families, I want to be able to offer an option that may be worth trying, she said.

Chen-Joea is a family medicine physician in Lakewood, California, and an adjunct faculty member for the Emanate Health Family Medicine Residency Program and the University of Southern California.

“Formula choice may feel insignificant,” said Chen-Joea. “This study suggests that formula choice from early on may matter more than we realized and can potentially make a big difference in a child’s life.”

Koletzko disclosed being on a speakers bureau for Mead Johnson Nutrition, a consultant for CAE Healthcare; his spouse employed by Mead Johnson Nutrition. Chen-Joea had no disclosures.