Data conflicting on whether emollients prevent atopic dermatitis in high-risk infants

Emollient use did not significantly prevent the development of atopic dermatitis among infants at high risk for the disease, according to a review presented at the European Academy of Allergy and Clinical Immunology Hybrid Congress.

However, the review of seven studies comparing early emollient use and good skin care practice among high-risk infants indicated a need to standardize study protocols before reaching a conclusion, Julia Cristina V. Gangoso, MD, of University of Santo Tomas Hospital in Manilla, Philippines, said during the presentation.

AD affects between 15% and 30% of children, Gangoso said, with up to 60% of cases presenting in the first year of life and 85% presenting within the first 5 years. Prevalence is increasing in developed and developing countries alike, she said.

“It has a significant impact on health care workers, [placing] financial, social and psychological burdens on health care workers, patients and their families,” Gangoso said.

The outside-in hypothesis posits that disrupted skin barriers play an important role not only in the initiation of AD but also in the entire atopic march of food allergies, allergic rhinitis and bronchial asthma, she continued.

“It has been proposed that the routine use of emollients can prevent the initial development of atopic dermatitis by ameliorating the skin barrier defects brought about by a change of lipid and protein composition and skin disbalances,” she said. “Emollient use remains a cornerstone in management of atopic dermatitis.”

The reviewed studies comprised 2,805 infants at high risk for AD and infants with a parent or sibling with atopic disease. According to the researchers, early emollient use led to a 21% risk reduction in the development of AD (RR = 0.79; 95% CI, 0.57-1.08), which did not reach significance.

However, there were differences in sample size, length of study, timing of initiation, control and binding, and other design details that may have accounted for the increased heterogeneity between the studies, the researchers said.

Also, the researchers found that the lack of a significant preventive effect likely was due to the studies using different emollient types, frequencies of application and timing of application commencement.

The researchers then conducted a subgroup analysis of six of the studies with a pooled population of 1,633 infants, including 814 in an intervention group and 819 in a control group, with 182 (22%) in the intervention group and 224 (27%) in the control group developing AD.

Based on these figures, early emollient use was associated with a 30% reduction in risk for AD (RR = 0.7; 95% CI, 0.51-0.95), which reached significance, reflecting the need to standardize protocols to truly determine the effectiveness of emollient use in preventing AD, the researchers said.

“There is a need to standardize study design details before a definitive conclusion may be made regarding the use of emollients as primary prevention for atopic dermatitis among high-risk infants,” Gangoso said. “It remains a promising intervention given the protective trends seen in the included studies.”