Microbial extract as a nature exposure material reduces the need for atopic dermatitis medication

Background: According to the biodiversity hypothesis, interaction with microbially rich natural environments reduces the risk of immune-mediated diseases, such as atopy, allergies, and asthma. Urban environments have been associated with a higher prevalence of these diseases, and beneficial immunological and microbiological changes have been observed when contact with microbiologically diverse materials has been re-established in intervention studies. Methods: The current study is the first large, randomized, double-blinded, placebo-controlled clinical trial to test the effect of biodiversity intervention on atopic dermatitis. The study involved 142 atopic dermatitis patients divided into two groups: the experimental group used a topical lotion with an inactivated, diverse microbial extract as nature exposure material, and the control group used the same lotion without the microbial extract. The use of atopy medications was not restricted, but it was carefully recorded. Atopy severity was monitored using validated EASI, POEM and NRS itch scales. Skin condition was evaluated by TEWL and erythema measurements, and medicine use was recorded with questionnaires. Results: There were fewer atopy medication users and fewer atopy medication days in the experimental group compared to the control group, despite the similarity in eczema severity between the groups. Inactivated microbial extract prevented the deterioration of barrier integrity and the increase in erythema observed during the winter in the control group. There was no difference in adverse effects between the groups. Conclusion: Our results indicate that a skin lotion containing this type of nature exposure material could offer a feasible and safe way to support current treatments in atopic dermatitis.