Effectiveness of Emollients in the Prevention of Atopic Dermatitis in Infants: A Meta-Analysis

Biologic and Small Molecule Therapy in Atopic Dermatitis

Atopic dermatitis is a chronic inflammatory dermatosis characterized by pruritic, scaly, erythematous lesions. Its incidence varies but is estimated to be approximately 20% in children and between 7 and 14% in adults, with variation amongst countries. It is a multifactorial condition, with a complex interplay between genetic, immunological, and environmental factors. Research into the inflammatory response has identified new therapeutic targets that work to reduce inflammation and subsequently reduce flares. This study explores existing therapeutic agents for atopic dermatitis as well as newer therapies such as biologics and small molecules, drawing upon each agent's mechanism of action, relevant landmark clinical trials, efficacy, and safety profile. Current therapies include emollients, corticosteroids, cyclosporine A, calcineurin inhibitors, phototherapy, and methotrexate. Biologics described include dupilumab, tralokinumab, lebrikizumab, nemolizumab, and rocatinlimab. Small molecules inhibitors include Janus kinase inhibitors, phosphodiesterase 4 inhibitors, transient receptor potential vanilloid subfamily V member 1 antagonist, and aryl hydrocarbon receptor antagonist.

Should Emollients Be Recommended for the Prevention of Atopic Dermatitis?-New Evidence and Current State of Knowledge

INTRODUCTION

Atopic dermatitis (AD) is a chronic, pruritic skin disease with complex pathogenesis, which affects about 43 million children aged 1-4 years. One of the most known methods of alleviating symptoms of AD is emollient treatment, which varies depending on formulation and additional active ingredients. There is some evidence that emollients could be used in AD prevention in high-risk children.

MATERIALS AND METHODS

A search of the literature from Cochrane Library, PubMed and Medline was conducted between August and September 2023 with the following keywords: "atopic dermatitis", "emollients", and "prevention". Only randomised clinical trials published in the last 5 years were included into the meta-analysis.

RESULTS

Considering the inclusion criteria only 11 randomized clinical trials were taken into account, and six of them proved lack of effect of emollients in the prevention of atopic dermatitis among neonates from AD risk groups.

CONCLUSIONS

Emollient treatment has a good safety profile and most of the ingredients used in formulations are nonirritant for sensitive newborn and infant skin. There is some evidence of the positive effects of emollient treatment in prevention of AD in predisposed populations. The relatively high cost of emollient treatment (vs regular infant skin-care routine) would support the necessity for further evaluation of their effectiveness in nonpredisposed populations.

Systematic review and network meta-analysis of different types of emollient for the prevention of atopic dermatitis in infants

Prophylactic application of emollients has been an effective strategy against infant atopic dermatitis (AD); however, the difference of different emollients is unknown. We performed this network meta-analysis to compare different emollients in preventing infant AD. A systematic search was performed in PubMed, EMBASE and Cochrane library to identify relevant studies from their inception through 28 February, 2022. We evaluated the quality of eligible studies using the Cochrane risk of bias assessment tool. Data analysis was performed using STATA 14.0. Eleven studies were included for data analysis. Direct meta-analysis suggested that early application of emollients effectively prevented AD development in high-risk infants (risk ratio [RR], 0.64; 95% confidence interval [CI], 0.47 to 0.88). Network meta-analysis suggested that emollient emulsion might the better option for preventing infant AD development, with a surface under the cumulative ranking curve (SUCRA) of 82.6% for all populations, 78.0% for high-risk populations and 79.2% for populations with food sensitization. Moreover, subjects receiving emollients more frequently experienced adverse events. Overall, early application of emollients is an effective strategy for preventing AD development in high-risk infants and emollient emulsion may be the optimal type. Future study with well-designed and large scale are warranted to validate our findings.

Moisturizer therapy in prevention of atopic dermatitis and food allergy: To use or disuse?

OBJECTIVE

To critically appraise the evidence for the role of regular moisturizer application in early life to prevent atopic dermatitis (AD) and food allergy (FA).

DATA SOURCES

Primary peer-reviewed literature.

STUDY SELECTIONS

Original research articles based on systematic reviews, interventional studies, retrospective studies, case-control studies, and cohort studies related to the subject matter.

RESULTS

There is good evidence to show that epicutaneous sensitization through a defective skin barrier is important in the development of AD and FA. This supports moisturizer use in prevention because some of them have been proven to restore skin barrier with clear benefits in AD, whereas there is some limited evidence that these products may reduce allergic sensitization. However, moisturizers have varied effects depending on ingredients and formulation, some of which are paradoxical, such as increasing transepidermal water loss and enhancing penetration of substances in the skin. These effects may be responsible for some of the conflicting outcomes of prevention studies, some of which suggest that moisturizers are not useful in prevention of AD and FA, whereas others show a positive trend. Interestingly, there is some suggestion that moisturizers may increase the risk for allergy development perhaps through these paradoxical effects.

CONCLUSION

Although moisturizer use is beneficial in the management of AD, current evidence suggests that it may be ineffective in prevention of AD and FA. Further studies are needed to determine the effects of moisturization on allergic sensitization and inflammation and to investigate whether moisturizer type, frequency, duration, and age of application substantially affect the prevention and development of these allergies.