Emollients don’t prevent atopic dermatitis (AD), but they might have untapped potential as treatment, two new studies suggest.
The results of a prevention study, in which parents slathered their babies with petrolatum, are particularly discouraging. Earlier studies had led researchers to hope this approach could stop not only AD but perhaps other related allergic conditions.
Instead, the babies who were in the petrolatum group in the Barrier Enhancement for Eczema Prevention Study (BEEP) were more likely to develop food allergies as well as skin infections than babies who received standard skin care.
“So, the parents of newborn babies should not be advised to use emollients to prevent eczema developing,” said Joanne Chalmers, PhD, a senior research fellow at the Center of Evidence Based Dermatology, University of Nottingham, Nottingham, United Kingdom.
In another study, an experimental nanofiber dressing impregnated with palmarosa oil significantly improved symptoms of the condition.
Both studies were presented at the International Society of Atopic Dermatitis (ISAD) 2021 Annual Meeting. The BEEP results were also published in The Lancet.
A “sizeable body of evidence” supports the use of emollients for the treatment of mild AD and flares, Chalmers said. Skin barrier dysfunction precedes the development of AD. Mutations in the filaggrin gene are associated with skin barrier dysfunction and the development of AD. There is no cure, and treatments are burdensome.
On the basis of these data, Chalmers and her colleagues thought applying emollients to babies was worth a try. They approached families with newborn babies who were at high risk of developing AD because they had at least one first-degree relative with AD, allergic rhinitis, or asthma.
They assigned 693 infants to the emollient group and 701 to the control group. They gave the families in the emollient group a choice of Doublebase Gel (Dermal Laboratories) or Diprobase Cream (Bayer). Both products contain petrolatum and have no ingredients known to have harmful effects. These products are commonly used in the UK National Health Service.
The researchers asked the families to apply the product they chose to their baby at least once daily. The products were to be applied to the whole body (excluding the scalp) until the baby reached age 1 year. They advised the families to apply emollient after every bath, even if they had already applied it earlier that day.
The control group was given standard advice: avoid harsh soaps and the use emollients unless the baby developed eczema.
Most families in the emollient group adhered to the regimen. Adherence dropped only slightly, from 88% at 3 months to 74% at 12 months, among those for whom complete questionnaire data were available.
This approach did not reduce risk. At 2 years, 23% of the babies in the emollient group and 25% in the control group developed AD, a difference that was not statistically significant (adjusted relative risk [aRR], 0.95; 95% CI, 0.78 – 1,16; P = .61]).
Of the 585 children in the emollient group, 15% developed skin infections during the first year, vs 11% of 589 babies in the control group. This was statistically significant. In the emollient group, the mean number of skin infections per child was 0.23, vs 0.15 in the control group (aRR, 1.55; 95% CI, 1.15 – 2.09).
Furthermore, at age 2 years, food allergies to milk, egg, or peanut were confirmed in 7% of the emollient group and in 5% of the control group. The difference was not statistically significant (aRR, 1.47; 95% CI; 0.93 – 2.33), but it was concerning, the researchers said.
They were surprised because the results contradicted the outcomes of their own pilot studies. They wondered whether newer emollients with better skin barrier properties might work better. They also mused about the possibility of a “complex intervention” involving such measures as low pH cleansers, infrequent washing, or softened water.
They emphasized that nothing about their findings should discourage the use of emollients as treatments for AD.
In a separate study of possible treatments, Seungsin Lee, PhD, and colleagues at Yonsei University, Seoul, South Korea, tried a new take on the traditional approach of wet wrapping.
They put palmarosa oil in nanofibrous bandages made with polyvinyl alcohol. Electrospun nanofibrous membranes have a microporous structure, a high specific surface area, and high porosity. These give the membranes flexibility and breathability, and they protect from external bacteria.
To test this combination as a treatment for AD, the researchers randomly assigned 30 patients with mild or moderate AD into three groups of 10 patients each. One group wore the nanofiber bandages with palmarosa oil, one wore dry bandages without palmarosa oil, and the third wore dry cotton gauze.
The patients wrapped arms or legs with the bandages and secured them with paper tape for 8 hours a night for 14 days. The Investigator’s Global Assessment (IGA) was used to assess effectiveness. Among both groups that wore the nanofiber bandages (one with palmarosa oil and one without), IGA scores regarding dermatitis symptoms declined from 2.2 to 1.7. The difference was statistically significant (P = .025).
IGA scores in the group wearing the cotton bandages increased from 1.7 to 1.9, which was not a significant change. Differences among the three groups were not significant, either.
Using the Scoring Atopic Dermatitis (SCORAD) scale, the findings were similar.
For the next 14 days, the researchers gave everyone in the study the nanofiber bandages. Symptoms improved significantly for all three groups.
Using the nanofiber bandages allowed the patients to reduce their use of steroid ointments. In surveys, the patients said they experienced less itching but that the bandages themselves were uncomfortable.
“In the future work, it would be useful to compare the atopic dermatitis relief effect of different types of essential oils known to be effective against atopic dermatitis when they are incorporated into nanofibrous membranes,” Lee said in an email. “In addition, further study is needed to improve the wearing comfort.”
Lee and Chalmers have disclosed no relevant financial relationships.
International Society of Atopic Dermatitis (ISAD) 2021 Annual Meeting: Abstract PT9 and oral session. Presented April 29, 2021.
Laird Harrison writes about science, health and culture. His work has appeared in magazines, newspapers , and online publications. He is at work on a novel about alternate realities in physics. Harrison has taught writing at San Francisco State University, UC Berkeley Extension and the Writers Grotto. Visit him at lairdharrison.com or follow him on Twitter: @LairdH.