Effects of Colloidal Oatmeal Topical Atopic Dermatitis Cream on Skin Microbiome and Skin Barrier Properties

May 2020 | Volume 19 | Issue 5 | Original Article | 524 | Copyright © May 2020

Published online April 17, 2020

Kimberly Capone , Frank Kirchner , Shifra Liba Klein , Neena K. Tierney

Johnson & Johnson Consumer Inc, Skillman, New Jersey

Abstract
Atopic dermatitis is characterized by dry, itchy, inflamed skin with a dysbiotic microbiome. In this clinical study (NCT03673059), we compared the effects of an eczema cream containing 1% colloidal oat and a standard moisturizer on the skin microbiome and skin barrier function of patients with mild to moderate eczema. Patients were randomly assigned to treatment with 1% colloidal oat eczema cream or a standard, non-fragranced daily moisturizer. Treatment lasted 14 days, followed by a 7-day regression period. Of 61 patients who completed the study, 30 received the 1% colloidal oat eczema cream and 31 received the standard moisturizer. At 14 days, the 1% colloidal oat eczema cream reduced mean Eczema Area Severity Index and Atopic Dermatitis Severity Index scores by 51% and 54%, respectively. Unlike treatment with the standard moisturizer, treatment with the 1% colloidal oat eczema cream was associated with trends towards lower prevalence of Staphylococcus species and higher microbiome diversity at lesion sites. The 1% colloidal oat eczema cream significantly improved skin pH, skin barrier function, and skin hydration from baseline to day 14, whereas the standard moisturizer improved hydration. Overall, the results demonstrate that topical products can have differing effects on the skin barrier properties and the microbiome. Importantly, we show that the use of a 1% colloidal oat eczema cream improves microbiome composition and significantly repairs skin barrier defects.

J Drugs Dermatol. 2020;19(5):   doi:10.36849/JDD.2020.4924

INTRODUCTION

Atopic dermatitis (AD), the most common form of eczema, is characterized by dry, itchy, scaly, and inflamed skin1 along with decreased diversity in the skin microbiome. Although AD is most prevalent in infants and children, it can persist throughout life, with an estimated prevalence among adults in the United States of 4.9%.2 Disease manifestations and symptoms such as skin lesions and severe itching can have a profound negative effect on quality of life (QOL), including sleep disturbances, psychological distress, interference with daily activities, and social isolation.1

Healthy skin is associated with an average skin surface pH <5.0, which supports the protective resident flora and helps to maintain skin barrier function.3,4 Patients with AD have a defective skin barrier,5 which typically results in increased skin pH,4,6 increased transdermal water loss (TEWL),7 and decreased skin hydration,8 particularly at lesion sites. Elevated skin surface pH can facilitate the proliferation of pathogenic bacteria, such as Staphylococcus aureus (S. aureus).4

AD is associated with decreased diversity of the skin microbiome and increased S. aureus colonization.9,10 Coagulase-negative staphylococci, such as Staphylococcus epidermidis (S. epidermidis), are predominant within the resident flora of healthy skin. S. epidermidis and Staphyloccocus hominis in particular are mutualistic organisms that help protect the skin against the colonization of potential pathogens.11 In contrast, S. aureus is a key pathogenic bacterium in AD that releases toxins and other molecules promoting skin barrier damage and inflammation.12 S. aureus has been shown to undergo clonal expansion and microevolution during disease flares,8 and S. aureus colonization has been associated with AD severity.13 Furthermore, AD is associated with increased risk of bacterial infections (most commonly by S. aureus and Streptococcus pyogenes) and viral infections.14

Although AD is often treated with moisturizing lotions and creams to alleviate AD-related symptoms such as itching, little is known about potential differences between these topical products in providing symptom relief. Furthermore, it remains unclear how various lotions and creams affect AD disease severity, and whether disease improvements with topical products are associated with alterations in microbial diversity.

This controlled clinical use study (ClinicalTrials.gov identifier: NCT03673059) evaluated the effects of a 1% colloidal oat eczema cream and a non-fragranced standard moisturizer on the skin microbiome, skin barrier function, skin hydration, and skin pH of patients with mild to moderate eczema over a 2-week treatment period, followed by a 1-week post-treatment regression period. The 1% colloidal oat eczema cream is an over-the-counter treatment for eczema containing 1% colloidal